--- /dev/null
+/*
+ * Ecmascript compiler.
+ *
+ * Parses an input string and generates a function template result.
+ * Compilation may happen in multiple contexts (global code, eval
+ * code, function code).
+ *
+ * The parser uses a traditional top-down recursive parsing for the
+ * statement level, and an operator precedence based top-down approach
+ * for the expression level. The attempt is to minimize the C stack
+ * depth. Bytecode is generated directly without an intermediate
+ * representation (tree), at the cost of needing two passes over each
+ * function.
+ *
+ * The top-down recursive parser functions are named "duk__parse_XXX".
+ *
+ * Recursion limits are in key functions to prevent arbitrary C recursion:
+ * function body parsing, statement parsing, and expression parsing.
+ *
+ * See doc/compiler.rst for discussion on the design.
+ *
+ * A few typing notes:
+ *
+ * - duk_regconst_t: unsigned, no marker value for "none"
+ * - duk_reg_t: signed, < 0 = none
+ * - PC values: duk_int_t, negative values used as markers
+ */
+
+#include "duk_internal.h"
+
+/* if highest bit of a register number is set, it refers to a constant instead */
+#define DUK__CONST_MARKER DUK_JS_CONST_MARKER
+
+/* for array and object literals */
+#define DUK__MAX_ARRAY_INIT_VALUES 20
+#define DUK__MAX_OBJECT_INIT_PAIRS 10
+
+/* XXX: hack, remove when const lookup is not O(n) */
+#define DUK__GETCONST_MAX_CONSTS_CHECK 256
+
+/* These limits are based on bytecode limits. Max temps is limited
+ * by duk_hcompiledfunction nargs/nregs fields being 16 bits.
+ */
+#define DUK__MAX_CONSTS DUK_BC_BC_MAX
+#define DUK__MAX_FUNCS DUK_BC_BC_MAX
+#define DUK__MAX_TEMPS 0xffffL
+
+/* Initial bytecode size allocation. */
+#define DUK__BC_INITIAL_INSTS 256
+
+#define DUK__RECURSION_INCREASE(comp_ctx,thr) do { \
+ DUK_DDD(DUK_DDDPRINT("RECURSION INCREASE: %s:%ld", (const char *) DUK_FILE_MACRO, (long) DUK_LINE_MACRO)); \
+ duk__recursion_increase((comp_ctx)); \
+ } while (0)
+
+#define DUK__RECURSION_DECREASE(comp_ctx,thr) do { \
+ DUK_DDD(DUK_DDDPRINT("RECURSION DECREASE: %s:%ld", (const char *) DUK_FILE_MACRO, (long) DUK_LINE_MACRO)); \
+ duk__recursion_decrease((comp_ctx)); \
+ } while (0)
+
+/* Value stack slot limits: these are quite approximate right now, and
+ * because they overlap in control flow, some could be eliminated.
+ */
+#define DUK__COMPILE_ENTRY_SLOTS 8
+#define DUK__FUNCTION_INIT_REQUIRE_SLOTS 16
+#define DUK__FUNCTION_BODY_REQUIRE_SLOTS 16
+#define DUK__PARSE_STATEMENTS_SLOTS 16
+#define DUK__PARSE_EXPR_SLOTS 16
+
+/* Temporary structure used to pass a stack allocated region through
+ * duk_safe_call().
+ */
+typedef struct {
+ duk_small_uint_t flags;
+ duk_compiler_ctx comp_ctx_alloc;
+ duk_lexer_point lex_pt_alloc;
+} duk__compiler_stkstate;
+
+/*
+ * Prototypes
+ */
+
+/* lexing */
+DUK_LOCAL_DECL void duk__advance_helper(duk_compiler_ctx *comp_ctx, duk_small_int_t expect);
+DUK_LOCAL_DECL void duk__advance_expect(duk_compiler_ctx *comp_ctx, duk_small_int_t expect);
+DUK_LOCAL_DECL void duk__advance(duk_compiler_ctx *ctx);
+
+/* function helpers */
+DUK_LOCAL_DECL void duk__init_func_valstack_slots(duk_compiler_ctx *comp_ctx);
+DUK_LOCAL_DECL void duk__reset_func_for_pass2(duk_compiler_ctx *comp_ctx);
+DUK_LOCAL_DECL void duk__init_varmap_and_prologue_for_pass2(duk_compiler_ctx *comp_ctx, duk_reg_t *out_stmt_value_reg);
+DUK_LOCAL_DECL void duk__convert_to_func_template(duk_compiler_ctx *comp_ctx, duk_bool_t force_no_namebind);
+DUK_LOCAL_DECL duk_int_t duk__cleanup_varmap(duk_compiler_ctx *comp_ctx);
+
+/* code emission */
+DUK_LOCAL_DECL duk_int_t duk__get_current_pc(duk_compiler_ctx *comp_ctx);
+DUK_LOCAL_DECL duk_compiler_instr *duk__get_instr_ptr(duk_compiler_ctx *comp_ctx, duk_int_t pc);
+DUK_LOCAL_DECL void duk__emit(duk_compiler_ctx *comp_ctx, duk_instr_t ins);
+#if 0 /* unused */
+DUK_LOCAL_DECL void duk__emit_op_only(duk_compiler_ctx *comp_ctx, duk_small_uint_t op);
+#endif
+DUK_LOCAL_DECL void duk__emit_a_b_c(duk_compiler_ctx *comp_ctx, duk_small_uint_t op_flags, duk_regconst_t a, duk_regconst_t b, duk_regconst_t c);
+DUK_LOCAL_DECL void duk__emit_a_b(duk_compiler_ctx *comp_ctx, duk_small_uint_t op_flags, duk_regconst_t a, duk_regconst_t b);
+#if 0 /* unused */
+DUK_LOCAL_DECL void duk__emit_a(duk_compiler_ctx *comp_ctx, duk_small_uint_t op_flags, duk_regconst_t a);
+#endif
+DUK_LOCAL_DECL void duk__emit_a_bc(duk_compiler_ctx *comp_ctx, duk_small_uint_t op_flags, duk_regconst_t a, duk_regconst_t bc);
+DUK_LOCAL_DECL void duk__emit_abc(duk_compiler_ctx *comp_ctx, duk_small_uint_t op, duk_regconst_t abc);
+DUK_LOCAL_DECL void duk__emit_extraop_b_c(duk_compiler_ctx *comp_ctx, duk_small_uint_t extraop_flags, duk_regconst_t b, duk_regconst_t c);
+DUK_LOCAL_DECL void duk__emit_extraop_b(duk_compiler_ctx *comp_ctx, duk_small_uint_t extraop_flags, duk_regconst_t b);
+DUK_LOCAL_DECL void duk__emit_extraop_bc(duk_compiler_ctx *comp_ctx, duk_small_uint_t extraop, duk_regconst_t bc);
+DUK_LOCAL_DECL void duk__emit_extraop_only(duk_compiler_ctx *comp_ctx, duk_small_uint_t extraop_flags);
+DUK_LOCAL_DECL void duk__emit_load_int32(duk_compiler_ctx *comp_ctx, duk_reg_t reg, duk_int32_t val);
+DUK_LOCAL_DECL void duk__emit_load_int32_noshuffle(duk_compiler_ctx *comp_ctx, duk_reg_t reg, duk_int32_t val);
+DUK_LOCAL_DECL void duk__emit_jump(duk_compiler_ctx *comp_ctx, duk_int_t target_pc);
+DUK_LOCAL_DECL duk_int_t duk__emit_jump_empty(duk_compiler_ctx *comp_ctx);
+DUK_LOCAL_DECL void duk__insert_jump_entry(duk_compiler_ctx *comp_ctx, duk_int_t jump_pc);
+DUK_LOCAL_DECL void duk__patch_jump(duk_compiler_ctx *comp_ctx, duk_int_t jump_pc, duk_int_t target_pc);
+DUK_LOCAL_DECL void duk__patch_jump_here(duk_compiler_ctx *comp_ctx, duk_int_t jump_pc);
+DUK_LOCAL_DECL void duk__patch_trycatch(duk_compiler_ctx *comp_ctx, duk_int_t ldconst_pc, duk_int_t trycatch_pc, duk_regconst_t reg_catch, duk_regconst_t const_varname, duk_small_uint_t flags);
+DUK_LOCAL_DECL void duk__emit_if_false_skip(duk_compiler_ctx *comp_ctx, duk_regconst_t regconst);
+DUK_LOCAL_DECL void duk__emit_if_true_skip(duk_compiler_ctx *comp_ctx, duk_regconst_t regconst);
+DUK_LOCAL_DECL void duk__emit_invalid(duk_compiler_ctx *comp_ctx);
+
+/* ivalue/ispec helpers */
+DUK_LOCAL_DECL void duk__copy_ispec(duk_compiler_ctx *comp_ctx, duk_ispec *src, duk_ispec *dst);
+DUK_LOCAL_DECL void duk__copy_ivalue(duk_compiler_ctx *comp_ctx, duk_ivalue *src, duk_ivalue *dst);
+DUK_LOCAL_DECL duk_bool_t duk__is_whole_get_int32(duk_double_t x, duk_int32_t *ival);
+DUK_LOCAL_DECL duk_reg_t duk__alloctemps(duk_compiler_ctx *comp_ctx, duk_small_int_t num);
+DUK_LOCAL_DECL duk_reg_t duk__alloctemp(duk_compiler_ctx *comp_ctx);
+DUK_LOCAL_DECL void duk__settemp_checkmax(duk_compiler_ctx *comp_ctx, duk_reg_t temp_next);
+DUK_LOCAL_DECL duk_regconst_t duk__getconst(duk_compiler_ctx *comp_ctx);
+DUK_LOCAL_DECL
+duk_regconst_t duk__ispec_toregconst_raw(duk_compiler_ctx *comp_ctx,
+ duk_ispec *x,
+ duk_reg_t forced_reg,
+ duk_small_uint_t flags);
+DUK_LOCAL_DECL void duk__ispec_toforcedreg(duk_compiler_ctx *comp_ctx, duk_ispec *x, duk_reg_t forced_reg);
+DUK_LOCAL_DECL void duk__ivalue_toplain_raw(duk_compiler_ctx *comp_ctx, duk_ivalue *x, duk_reg_t forced_reg);
+DUK_LOCAL_DECL void duk__ivalue_toplain(duk_compiler_ctx *comp_ctx, duk_ivalue *x);
+DUK_LOCAL_DECL void duk__ivalue_toplain_ignore(duk_compiler_ctx *comp_ctx, duk_ivalue *x);
+DUK_LOCAL_DECL
+duk_regconst_t duk__ivalue_toregconst_raw(duk_compiler_ctx *comp_ctx,
+ duk_ivalue *x,
+ duk_reg_t forced_reg,
+ duk_small_uint_t flags);
+DUK_LOCAL_DECL duk_reg_t duk__ivalue_toreg(duk_compiler_ctx *comp_ctx, duk_ivalue *x);
+#if 0 /* unused */
+DUK_LOCAL_DECL duk_reg_t duk__ivalue_totemp(duk_compiler_ctx *comp_ctx, duk_ivalue *x);
+#endif
+DUK_LOCAL_DECL void duk__ivalue_toforcedreg(duk_compiler_ctx *comp_ctx, duk_ivalue *x, duk_int_t forced_reg);
+DUK_LOCAL_DECL duk_regconst_t duk__ivalue_toregconst(duk_compiler_ctx *comp_ctx, duk_ivalue *x);
+DUK_LOCAL_DECL duk_regconst_t duk__ivalue_totempconst(duk_compiler_ctx *comp_ctx, duk_ivalue *x);
+
+/* identifier handling */
+DUK_LOCAL_DECL duk_reg_t duk__lookup_active_register_binding(duk_compiler_ctx *comp_ctx);
+DUK_LOCAL_DECL duk_bool_t duk__lookup_lhs(duk_compiler_ctx *ctx, duk_reg_t *out_reg_varbind, duk_regconst_t *out_rc_varname);
+
+/* label handling */
+DUK_LOCAL_DECL void duk__add_label(duk_compiler_ctx *comp_ctx, duk_hstring *h_label, duk_int_t pc_label, duk_int_t label_id);
+DUK_LOCAL_DECL void duk__update_label_flags(duk_compiler_ctx *comp_ctx, duk_int_t label_id, duk_small_uint_t flags);
+DUK_LOCAL_DECL void duk__lookup_active_label(duk_compiler_ctx *comp_ctx, duk_hstring *h_label, duk_bool_t is_break, duk_int_t *out_label_id, duk_int_t *out_label_catch_depth, duk_int_t *out_label_pc, duk_bool_t *out_is_closest);
+DUK_LOCAL_DECL void duk__reset_labels_to_length(duk_compiler_ctx *comp_ctx, duk_int_t len);
+
+/* top-down expression parser */
+DUK_LOCAL_DECL void duk__expr_nud(duk_compiler_ctx *comp_ctx, duk_ivalue *res);
+DUK_LOCAL_DECL void duk__expr_led(duk_compiler_ctx *comp_ctx, duk_ivalue *left, duk_ivalue *res);
+DUK_LOCAL_DECL duk_small_uint_t duk__expr_lbp(duk_compiler_ctx *comp_ctx);
+DUK_LOCAL_DECL duk_bool_t duk__expr_is_empty(duk_compiler_ctx *comp_ctx);
+
+/* exprtop is the top level variant which resets nud/led counts */
+DUK_LOCAL_DECL void duk__expr(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags);
+DUK_LOCAL_DECL void duk__exprtop(duk_compiler_ctx *ctx, duk_ivalue *res, duk_small_uint_t rbp_flags);
+
+/* convenience helpers */
+#if 0 /* unused */
+DUK_LOCAL_DECL duk_reg_t duk__expr_toreg(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags);
+#endif
+#if 0 /* unused */
+DUK_LOCAL_DECL duk_reg_t duk__expr_totemp(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags);
+#endif
+DUK_LOCAL_DECL void duk__expr_toforcedreg(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags, duk_reg_t forced_reg);
+DUK_LOCAL_DECL duk_regconst_t duk__expr_toregconst(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags);
+#if 0 /* unused */
+DUK_LOCAL_DECL duk_regconst_t duk__expr_totempconst(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags);
+#endif
+DUK_LOCAL_DECL void duk__expr_toplain(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags);
+DUK_LOCAL_DECL void duk__expr_toplain_ignore(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags);
+DUK_LOCAL_DECL duk_reg_t duk__exprtop_toreg(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags);
+#if 0 /* unused */
+DUK_LOCAL_DECL duk_reg_t duk__exprtop_totemp(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags);
+#endif
+DUK_LOCAL_DECL void duk__exprtop_toforcedreg(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags, duk_reg_t forced_reg);
+DUK_LOCAL_DECL duk_regconst_t duk__exprtop_toregconst(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags);
+#if 0 /* unused */
+DUK_LOCAL_DECL void duk__exprtop_toplain_ignore(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags);
+#endif
+
+/* expression parsing helpers */
+DUK_LOCAL_DECL duk_int_t duk__parse_arguments(duk_compiler_ctx *comp_ctx, duk_ivalue *res);
+DUK_LOCAL_DECL void duk__nud_array_literal(duk_compiler_ctx *comp_ctx, duk_ivalue *res);
+DUK_LOCAL_DECL void duk__nud_object_literal(duk_compiler_ctx *comp_ctx, duk_ivalue *res);
+DUK_LOCAL_DECL duk_bool_t duk__nud_object_literal_key_check(duk_compiler_ctx *comp_ctx, duk_small_uint_t new_key_flags);
+
+/* statement parsing */
+DUK_LOCAL_DECL void duk__parse_var_decl(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t expr_flags, duk_reg_t *out_reg_varbind, duk_regconst_t *out_rc_varname);
+DUK_LOCAL_DECL void duk__parse_var_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t expr_flags);
+DUK_LOCAL_DECL void duk__parse_for_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_int_t pc_label_site);
+DUK_LOCAL_DECL void duk__parse_switch_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_int_t pc_label_site);
+DUK_LOCAL_DECL void duk__parse_if_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res);
+DUK_LOCAL_DECL void duk__parse_do_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_int_t pc_label_site);
+DUK_LOCAL_DECL void duk__parse_while_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_int_t pc_label_site);
+DUK_LOCAL_DECL void duk__parse_break_or_continue_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res);
+DUK_LOCAL_DECL void duk__parse_return_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res);
+DUK_LOCAL_DECL void duk__parse_throw_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res);
+DUK_LOCAL_DECL void duk__parse_try_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res);
+DUK_LOCAL_DECL void duk__parse_with_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res);
+DUK_LOCAL_DECL void duk__parse_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_bool_t allow_source_elem);
+DUK_LOCAL_DECL duk_int_t duk__stmt_label_site(duk_compiler_ctx *comp_ctx, duk_int_t label_id);
+DUK_LOCAL_DECL void duk__parse_stmts(duk_compiler_ctx *comp_ctx, duk_bool_t allow_source_elem, duk_bool_t expect_eof);
+
+DUK_LOCAL_DECL void duk__parse_func_body(duk_compiler_ctx *comp_ctx, duk_bool_t expect_eof, duk_bool_t implicit_return_value, duk_small_int_t expect_token);
+DUK_LOCAL_DECL void duk__parse_func_formals(duk_compiler_ctx *comp_ctx);
+DUK_LOCAL_DECL void duk__parse_func_like_raw(duk_compiler_ctx *comp_ctx, duk_bool_t is_decl, duk_bool_t is_setget);
+DUK_LOCAL_DECL duk_int_t duk__parse_func_like_fnum(duk_compiler_ctx *comp_ctx, duk_bool_t is_decl, duk_bool_t is_setget);
+
+/*
+ * Parser control values for tokens. The token table is ordered by the
+ * DUK_TOK_XXX defines.
+ *
+ * The binding powers are for lbp() use (i.e. for use in led() context).
+ * Binding powers are positive for typing convenience, and bits at the
+ * top should be reserved for flags. Binding power step must be higher
+ * than 1 so that binding power "lbp - 1" can be used for right associative
+ * operators. Currently a step of 2 is used (which frees one more bit for
+ * flags).
+ */
+
+/* XXX: actually single step levels would work just fine, clean up */
+
+/* binding power "levels" (see doc/compiler.rst) */
+#define DUK__BP_INVALID 0 /* always terminates led() */
+#define DUK__BP_EOF 2
+#define DUK__BP_CLOSING 4 /* token closes expression, e.g. ')', ']' */
+#define DUK__BP_FOR_EXPR DUK__BP_CLOSING /* bp to use when parsing a top level Expression */
+#define DUK__BP_COMMA 6
+#define DUK__BP_ASSIGNMENT 8
+#define DUK__BP_CONDITIONAL 10
+#define DUK__BP_LOR 12
+#define DUK__BP_LAND 14
+#define DUK__BP_BOR 16
+#define DUK__BP_BXOR 18
+#define DUK__BP_BAND 20
+#define DUK__BP_EQUALITY 22
+#define DUK__BP_RELATIONAL 24
+#define DUK__BP_SHIFT 26
+#define DUK__BP_ADDITIVE 28
+#define DUK__BP_MULTIPLICATIVE 30
+#define DUK__BP_POSTFIX 32
+#define DUK__BP_CALL 34
+#define DUK__BP_MEMBER 36
+
+#define DUK__TOKEN_LBP_BP_MASK 0x1f
+#define DUK__TOKEN_LBP_FLAG_NO_REGEXP (1 << 5) /* regexp literal must not follow this token */
+#define DUK__TOKEN_LBP_FLAG_TERMINATES (1 << 6) /* terminates expression; e.g. post-increment/-decrement */
+#define DUK__TOKEN_LBP_FLAG_UNUSED (1 << 7) /* spare */
+
+#define DUK__TOKEN_LBP_GET_BP(x) ((duk_small_uint_t) (((x) & DUK__TOKEN_LBP_BP_MASK) * 2))
+
+#define DUK__MK_LBP(bp) ((bp) >> 1) /* bp is assumed to be even */
+#define DUK__MK_LBP_FLAGS(bp,flags) (((bp) >> 1) | (flags))
+
+DUK_LOCAL const duk_uint8_t duk__token_lbp[] = {
+ DUK__MK_LBP(DUK__BP_EOF), /* DUK_TOK_EOF */
+ DUK__MK_LBP_FLAGS(DUK__BP_INVALID, DUK__TOKEN_LBP_FLAG_NO_REGEXP), /* DUK_TOK_IDENTIFIER */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_BREAK */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_CASE */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_CATCH */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_CONTINUE */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_DEBUGGER */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_DEFAULT */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_DELETE */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_DO */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_ELSE */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_FINALLY */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_FOR */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_FUNCTION */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_IF */
+ DUK__MK_LBP(DUK__BP_RELATIONAL), /* DUK_TOK_IN */
+ DUK__MK_LBP(DUK__BP_RELATIONAL), /* DUK_TOK_INSTANCEOF */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_NEW */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_RETURN */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_SWITCH */
+ DUK__MK_LBP_FLAGS(DUK__BP_INVALID, DUK__TOKEN_LBP_FLAG_NO_REGEXP), /* DUK_TOK_THIS */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_THROW */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_TRY */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_TYPEOF */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_VAR */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_CONST */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_VOID */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_WHILE */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_WITH */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_CLASS */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_ENUM */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_EXPORT */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_EXTENDS */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_IMPORT */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_SUPER */
+ DUK__MK_LBP_FLAGS(DUK__BP_INVALID, DUK__TOKEN_LBP_FLAG_NO_REGEXP), /* DUK_TOK_NULL */
+ DUK__MK_LBP_FLAGS(DUK__BP_INVALID, DUK__TOKEN_LBP_FLAG_NO_REGEXP), /* DUK_TOK_TRUE */
+ DUK__MK_LBP_FLAGS(DUK__BP_INVALID, DUK__TOKEN_LBP_FLAG_NO_REGEXP), /* DUK_TOK_FALSE */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_GET */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_SET */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_IMPLEMENTS */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_INTERFACE */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_LET */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_PACKAGE */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_PRIVATE */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_PROTECTED */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_PUBLIC */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_STATIC */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_YIELD */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_LCURLY */
+ DUK__MK_LBP_FLAGS(DUK__BP_INVALID, DUK__TOKEN_LBP_FLAG_NO_REGEXP), /* DUK_TOK_RCURLY */
+ DUK__MK_LBP(DUK__BP_MEMBER), /* DUK_TOK_LBRACKET */
+ DUK__MK_LBP_FLAGS(DUK__BP_CLOSING, DUK__TOKEN_LBP_FLAG_NO_REGEXP), /* DUK_TOK_RBRACKET */
+ DUK__MK_LBP(DUK__BP_CALL), /* DUK_TOK_LPAREN */
+ DUK__MK_LBP_FLAGS(DUK__BP_CLOSING, DUK__TOKEN_LBP_FLAG_NO_REGEXP), /* DUK_TOK_RPAREN */
+ DUK__MK_LBP(DUK__BP_MEMBER), /* DUK_TOK_PERIOD */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_SEMICOLON */
+ DUK__MK_LBP(DUK__BP_COMMA), /* DUK_TOK_COMMA */
+ DUK__MK_LBP(DUK__BP_RELATIONAL), /* DUK_TOK_LT */
+ DUK__MK_LBP(DUK__BP_RELATIONAL), /* DUK_TOK_GT */
+ DUK__MK_LBP(DUK__BP_RELATIONAL), /* DUK_TOK_LE */
+ DUK__MK_LBP(DUK__BP_RELATIONAL), /* DUK_TOK_GE */
+ DUK__MK_LBP(DUK__BP_EQUALITY), /* DUK_TOK_EQ */
+ DUK__MK_LBP(DUK__BP_EQUALITY), /* DUK_TOK_NEQ */
+ DUK__MK_LBP(DUK__BP_EQUALITY), /* DUK_TOK_SEQ */
+ DUK__MK_LBP(DUK__BP_EQUALITY), /* DUK_TOK_SNEQ */
+ DUK__MK_LBP(DUK__BP_ADDITIVE), /* DUK_TOK_ADD */
+ DUK__MK_LBP(DUK__BP_ADDITIVE), /* DUK_TOK_SUB */
+ DUK__MK_LBP(DUK__BP_MULTIPLICATIVE), /* DUK_TOK_MUL */
+ DUK__MK_LBP(DUK__BP_MULTIPLICATIVE), /* DUK_TOK_DIV */
+ DUK__MK_LBP(DUK__BP_MULTIPLICATIVE), /* DUK_TOK_MOD */
+ DUK__MK_LBP(DUK__BP_POSTFIX), /* DUK_TOK_INCREMENT */
+ DUK__MK_LBP(DUK__BP_POSTFIX), /* DUK_TOK_DECREMENT */
+ DUK__MK_LBP(DUK__BP_SHIFT), /* DUK_TOK_ALSHIFT */
+ DUK__MK_LBP(DUK__BP_SHIFT), /* DUK_TOK_ARSHIFT */
+ DUK__MK_LBP(DUK__BP_SHIFT), /* DUK_TOK_RSHIFT */
+ DUK__MK_LBP(DUK__BP_BAND), /* DUK_TOK_BAND */
+ DUK__MK_LBP(DUK__BP_BOR), /* DUK_TOK_BOR */
+ DUK__MK_LBP(DUK__BP_BXOR), /* DUK_TOK_BXOR */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_LNOT */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_BNOT */
+ DUK__MK_LBP(DUK__BP_LAND), /* DUK_TOK_LAND */
+ DUK__MK_LBP(DUK__BP_LOR), /* DUK_TOK_LOR */
+ DUK__MK_LBP(DUK__BP_CONDITIONAL), /* DUK_TOK_QUESTION */
+ DUK__MK_LBP(DUK__BP_INVALID), /* DUK_TOK_COLON */
+ DUK__MK_LBP(DUK__BP_ASSIGNMENT), /* DUK_TOK_EQUALSIGN */
+ DUK__MK_LBP(DUK__BP_ASSIGNMENT), /* DUK_TOK_ADD_EQ */
+ DUK__MK_LBP(DUK__BP_ASSIGNMENT), /* DUK_TOK_SUB_EQ */
+ DUK__MK_LBP(DUK__BP_ASSIGNMENT), /* DUK_TOK_MUL_EQ */
+ DUK__MK_LBP(DUK__BP_ASSIGNMENT), /* DUK_TOK_DIV_EQ */
+ DUK__MK_LBP(DUK__BP_ASSIGNMENT), /* DUK_TOK_MOD_EQ */
+ DUK__MK_LBP(DUK__BP_ASSIGNMENT), /* DUK_TOK_ALSHIFT_EQ */
+ DUK__MK_LBP(DUK__BP_ASSIGNMENT), /* DUK_TOK_ARSHIFT_EQ */
+ DUK__MK_LBP(DUK__BP_ASSIGNMENT), /* DUK_TOK_RSHIFT_EQ */
+ DUK__MK_LBP(DUK__BP_ASSIGNMENT), /* DUK_TOK_BAND_EQ */
+ DUK__MK_LBP(DUK__BP_ASSIGNMENT), /* DUK_TOK_BOR_EQ */
+ DUK__MK_LBP(DUK__BP_ASSIGNMENT), /* DUK_TOK_BXOR_EQ */
+ DUK__MK_LBP_FLAGS(DUK__BP_INVALID, DUK__TOKEN_LBP_FLAG_NO_REGEXP), /* DUK_TOK_NUMBER */
+ DUK__MK_LBP_FLAGS(DUK__BP_INVALID, DUK__TOKEN_LBP_FLAG_NO_REGEXP), /* DUK_TOK_STRING */
+ DUK__MK_LBP_FLAGS(DUK__BP_INVALID, DUK__TOKEN_LBP_FLAG_NO_REGEXP), /* DUK_TOK_REGEXP */
+};
+
+/*
+ * Misc helpers
+ */
+
+DUK_LOCAL void duk__recursion_increase(duk_compiler_ctx *comp_ctx) {
+ DUK_ASSERT(comp_ctx != NULL);
+ DUK_ASSERT(comp_ctx->recursion_depth >= 0);
+ if (comp_ctx->recursion_depth >= comp_ctx->recursion_limit) {
+ DUK_ERROR_RANGE(comp_ctx->thr, DUK_STR_COMPILER_RECURSION_LIMIT);
+ }
+ comp_ctx->recursion_depth++;
+}
+
+DUK_LOCAL void duk__recursion_decrease(duk_compiler_ctx *comp_ctx) {
+ DUK_ASSERT(comp_ctx != NULL);
+ DUK_ASSERT(comp_ctx->recursion_depth > 0);
+ comp_ctx->recursion_depth--;
+}
+
+DUK_LOCAL duk_bool_t duk__hstring_is_eval_or_arguments(duk_compiler_ctx *comp_ctx, duk_hstring *h) {
+ DUK_UNREF(comp_ctx);
+ DUK_ASSERT(h != NULL);
+ return DUK_HSTRING_HAS_EVAL_OR_ARGUMENTS(h);
+}
+
+DUK_LOCAL duk_bool_t duk__hstring_is_eval_or_arguments_in_strict_mode(duk_compiler_ctx *comp_ctx, duk_hstring *h) {
+ DUK_ASSERT(h != NULL);
+ return (comp_ctx->curr_func.is_strict &&
+ DUK_HSTRING_HAS_EVAL_OR_ARGUMENTS(h));
+}
+
+/*
+ * Parser duk__advance() token eating functions
+ */
+
+/* XXX: valstack handling is awkward. Add a valstack helper which
+ * avoids dup():ing; valstack_copy(src, dst)?
+ */
+
+DUK_LOCAL void duk__advance_helper(duk_compiler_ctx *comp_ctx, duk_small_int_t expect) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_bool_t regexp;
+
+ DUK_ASSERT(comp_ctx->curr_token.t >= 0 && comp_ctx->curr_token.t <= DUK_TOK_MAXVAL); /* MAXVAL is inclusive */
+
+ /*
+ * Use current token to decide whether a RegExp can follow.
+ *
+ * We can use either 't' or 't_nores'; the latter would not
+ * recognize keywords. Some keywords can be followed by a
+ * RegExp (e.g. "return"), so using 't' is better. This is
+ * not trivial, see doc/compiler.rst.
+ */
+
+ regexp = 1;
+ if (duk__token_lbp[comp_ctx->curr_token.t] & DUK__TOKEN_LBP_FLAG_NO_REGEXP) {
+ regexp = 0;
+ }
+ if (comp_ctx->curr_func.reject_regexp_in_adv) {
+ comp_ctx->curr_func.reject_regexp_in_adv = 0;
+ regexp = 0;
+ }
+
+ if (expect >= 0 && comp_ctx->curr_token.t != expect) {
+ DUK_D(DUK_DPRINT("parse error: expect=%ld, got=%ld",
+ (long) expect, (long) comp_ctx->curr_token.t));
+ DUK_ERROR_SYNTAX(thr, DUK_STR_PARSE_ERROR);
+ }
+
+ /* make current token the previous; need to fiddle with valstack "backing store" */
+ DUK_MEMCPY(&comp_ctx->prev_token, &comp_ctx->curr_token, sizeof(duk_token));
+ duk_copy(ctx, comp_ctx->tok11_idx, comp_ctx->tok21_idx);
+ duk_copy(ctx, comp_ctx->tok12_idx, comp_ctx->tok22_idx);
+
+ /* parse new token */
+ duk_lexer_parse_js_input_element(&comp_ctx->lex,
+ &comp_ctx->curr_token,
+ comp_ctx->curr_func.is_strict,
+ regexp);
+
+ DUK_DDD(DUK_DDDPRINT("advance: curr: tok=%ld/%ld,%ld,term=%ld,%!T,%!T "
+ "prev: tok=%ld/%ld,%ld,term=%ld,%!T,%!T",
+ (long) comp_ctx->curr_token.t,
+ (long) comp_ctx->curr_token.t_nores,
+ (long) comp_ctx->curr_token.start_line,
+ (long) comp_ctx->curr_token.lineterm,
+ (duk_tval *) duk_get_tval(ctx, comp_ctx->tok11_idx),
+ (duk_tval *) duk_get_tval(ctx, comp_ctx->tok12_idx),
+ (long) comp_ctx->prev_token.t,
+ (long) comp_ctx->prev_token.t_nores,
+ (long) comp_ctx->prev_token.start_line,
+ (long) comp_ctx->prev_token.lineterm,
+ (duk_tval *) duk_get_tval(ctx, comp_ctx->tok21_idx),
+ (duk_tval *) duk_get_tval(ctx, comp_ctx->tok22_idx)));
+}
+
+/* advance, expecting current token to be a specific token; parse next token in regexp context */
+DUK_LOCAL void duk__advance_expect(duk_compiler_ctx *comp_ctx, duk_small_int_t expect) {
+ duk__advance_helper(comp_ctx, expect);
+}
+
+/* advance, whatever the current token is; parse next token in regexp context */
+DUK_LOCAL void duk__advance(duk_compiler_ctx *comp_ctx) {
+ duk__advance_helper(comp_ctx, -1);
+}
+
+/*
+ * Helpers for duk_compiler_func.
+ */
+
+/* init function state: inits valstack allocations */
+DUK_LOCAL void duk__init_func_valstack_slots(duk_compiler_ctx *comp_ctx) {
+ duk_compiler_func *func = &comp_ctx->curr_func;
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_idx_t entry_top;
+
+ entry_top = duk_get_top(ctx);
+
+ DUK_MEMZERO(func, sizeof(*func)); /* intentional overlap with earlier memzero */
+#ifdef DUK_USE_EXPLICIT_NULL_INIT
+ func->h_name = NULL;
+ func->h_consts = NULL;
+ func->h_funcs = NULL;
+ func->h_decls = NULL;
+ func->h_labelnames = NULL;
+ func->h_labelinfos = NULL;
+ func->h_argnames = NULL;
+ func->h_varmap = NULL;
+#endif
+
+ duk_require_stack(ctx, DUK__FUNCTION_INIT_REQUIRE_SLOTS);
+
+ DUK_BW_INIT_PUSHBUF(thr, &func->bw_code, DUK__BC_INITIAL_INSTS * sizeof(duk_compiler_instr));
+ /* code_idx = entry_top + 0 */
+
+ duk_push_array(ctx);
+ func->consts_idx = entry_top + 1;
+ func->h_consts = DUK_GET_HOBJECT_POSIDX(ctx, entry_top + 1);
+ DUK_ASSERT(func->h_consts != NULL);
+
+ duk_push_array(ctx);
+ func->funcs_idx = entry_top + 2;
+ func->h_funcs = DUK_GET_HOBJECT_POSIDX(ctx, entry_top + 2);
+ DUK_ASSERT(func->h_funcs != NULL);
+ DUK_ASSERT(func->fnum_next == 0);
+
+ duk_push_array(ctx);
+ func->decls_idx = entry_top + 3;
+ func->h_decls = DUK_GET_HOBJECT_POSIDX(ctx, entry_top + 3);
+ DUK_ASSERT(func->h_decls != NULL);
+
+ duk_push_array(ctx);
+ func->labelnames_idx = entry_top + 4;
+ func->h_labelnames = DUK_GET_HOBJECT_POSIDX(ctx, entry_top + 4);
+ DUK_ASSERT(func->h_labelnames != NULL);
+
+ duk_push_dynamic_buffer(ctx, 0);
+ func->labelinfos_idx = entry_top + 5;
+ func->h_labelinfos = (duk_hbuffer_dynamic *) duk_get_hbuffer(ctx, entry_top + 5);
+ DUK_ASSERT(func->h_labelinfos != NULL);
+ DUK_ASSERT(DUK_HBUFFER_HAS_DYNAMIC(func->h_labelinfos) && !DUK_HBUFFER_HAS_EXTERNAL(func->h_labelinfos));
+
+ duk_push_array(ctx);
+ func->argnames_idx = entry_top + 6;
+ func->h_argnames = DUK_GET_HOBJECT_POSIDX(ctx, entry_top + 6);
+ DUK_ASSERT(func->h_argnames != NULL);
+
+ duk_push_object_internal(ctx);
+ func->varmap_idx = entry_top + 7;
+ func->h_varmap = DUK_GET_HOBJECT_POSIDX(ctx, entry_top + 7);
+ DUK_ASSERT(func->h_varmap != NULL);
+}
+
+/* reset function state (prepare for pass 2) */
+DUK_LOCAL void duk__reset_func_for_pass2(duk_compiler_ctx *comp_ctx) {
+ duk_compiler_func *func = &comp_ctx->curr_func;
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+
+ /* reset bytecode buffer but keep current size; pass 2 will
+ * require same amount or more.
+ */
+ DUK_BW_RESET_SIZE(thr, &func->bw_code);
+
+ duk_hobject_set_length_zero(thr, func->h_consts);
+ /* keep func->h_funcs; inner functions are not reparsed to avoid O(depth^2) parsing */
+ func->fnum_next = 0;
+ /* duk_hobject_set_length_zero(thr, func->h_funcs); */
+ duk_hobject_set_length_zero(thr, func->h_labelnames);
+ duk_hbuffer_reset(thr, func->h_labelinfos);
+ /* keep func->h_argnames; it is fixed for all passes */
+
+ /* truncated in case pass 3 needed */
+ duk_push_object_internal(ctx);
+ duk_replace(ctx, func->varmap_idx);
+ func->h_varmap = DUK_GET_HOBJECT_POSIDX(ctx, func->varmap_idx);
+ DUK_ASSERT(func->h_varmap != NULL);
+}
+
+/* cleanup varmap from any null entries, compact it, etc; returns number
+ * of final entries after cleanup.
+ */
+DUK_LOCAL duk_int_t duk__cleanup_varmap(duk_compiler_ctx *comp_ctx) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_hobject *h_varmap;
+ duk_hstring *h_key;
+ duk_tval *tv;
+ duk_uint32_t i, e_next;
+ duk_int_t ret;
+
+ /* [ ... varmap ] */
+
+ h_varmap = DUK_GET_HOBJECT_NEGIDX(ctx, -1);
+ DUK_ASSERT(h_varmap != NULL);
+
+ ret = 0;
+ e_next = DUK_HOBJECT_GET_ENEXT(h_varmap);
+ for (i = 0; i < e_next; i++) {
+ h_key = DUK_HOBJECT_E_GET_KEY(thr->heap, h_varmap, i);
+ if (!h_key) {
+ continue;
+ }
+
+ DUK_ASSERT(!DUK_HOBJECT_E_SLOT_IS_ACCESSOR(thr->heap, h_varmap, i));
+
+ /* The entries can either be register numbers or 'null' values.
+ * Thus, no need to DECREF them and get side effects. DECREF'ing
+ * the keys (strings) can cause memory to be freed but no side
+ * effects as strings don't have finalizers. This is why we can
+ * rely on the object properties not changing from underneath us.
+ */
+
+ tv = DUK_HOBJECT_E_GET_VALUE_TVAL_PTR(thr->heap, h_varmap, i);
+ if (!DUK_TVAL_IS_NUMBER(tv)) {
+ DUK_ASSERT(!DUK_TVAL_IS_HEAP_ALLOCATED(tv));
+ DUK_HOBJECT_E_SET_KEY(thr->heap, h_varmap, i, NULL);
+ DUK_HSTRING_DECREF(thr, h_key);
+ /* when key is NULL, value is garbage so no need to set */
+ } else {
+ ret++;
+ }
+ }
+
+ duk_compact(ctx, -1);
+
+ return ret;
+}
+
+/* convert duk_compiler_func into a function template, leaving the result
+ * on top of stack.
+ */
+/* XXX: awkward and bloated asm -- use faster internal accesses */
+DUK_LOCAL void duk__convert_to_func_template(duk_compiler_ctx *comp_ctx, duk_bool_t force_no_namebind) {
+ duk_compiler_func *func = &comp_ctx->curr_func;
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_hcompiledfunction *h_res;
+ duk_hbuffer_fixed *h_data;
+ duk_size_t consts_count;
+ duk_size_t funcs_count;
+ duk_size_t code_count;
+ duk_size_t code_size;
+ duk_size_t data_size;
+ duk_size_t i;
+ duk_tval *p_const;
+ duk_hobject **p_func;
+ duk_instr_t *p_instr;
+ duk_compiler_instr *q_instr;
+ duk_tval *tv;
+
+ DUK_DDD(DUK_DDDPRINT("converting duk_compiler_func to function/template"));
+
+ /*
+ * Push result object and init its flags
+ */
+
+ /* Valstack should suffice here, required on function valstack init */
+
+ (void) duk_push_compiledfunction(ctx);
+ h_res = (duk_hcompiledfunction *) DUK_GET_HOBJECT_NEGIDX(ctx, -1); /* XXX: specific getter */
+ DUK_ASSERT(h_res != NULL);
+
+ if (func->is_function) {
+ DUK_DDD(DUK_DDDPRINT("function -> set NEWENV"));
+ DUK_HOBJECT_SET_NEWENV((duk_hobject *) h_res);
+
+ if (!func->is_arguments_shadowed) {
+ /* arguments object would be accessible; note that shadowing
+ * bindings are arguments or function declarations, neither
+ * of which are deletable, so this is safe.
+ */
+
+ if (func->id_access_arguments || func->may_direct_eval) {
+ DUK_DDD(DUK_DDDPRINT("function may access 'arguments' object directly or "
+ "indirectly -> set CREATEARGS"));
+ DUK_HOBJECT_SET_CREATEARGS((duk_hobject *) h_res);
+ }
+ }
+ } else if (func->is_eval && func->is_strict) {
+ DUK_DDD(DUK_DDDPRINT("strict eval code -> set NEWENV"));
+ DUK_HOBJECT_SET_NEWENV((duk_hobject *) h_res);
+ } else {
+ /* non-strict eval: env is caller's env or global env (direct vs. indirect call)
+ * global code: env is is global env
+ */
+ DUK_DDD(DUK_DDDPRINT("non-strict eval code or global code -> no NEWENV"));
+ DUK_ASSERT(!DUK_HOBJECT_HAS_NEWENV((duk_hobject *) h_res));
+ }
+
+ if (func->is_function && !func->is_decl && func->h_name != NULL && !force_no_namebind) {
+ /* Object literal set/get functions have a name (property
+ * name) but must not have a lexical name binding, see
+ * test-bug-getset-func-name.js.
+ */
+ DUK_DDD(DUK_DDDPRINT("function expression with a name -> set NAMEBINDING"));
+ DUK_HOBJECT_SET_NAMEBINDING((duk_hobject *) h_res);
+ }
+
+ if (func->is_strict) {
+ DUK_DDD(DUK_DDDPRINT("function is strict -> set STRICT"));
+ DUK_HOBJECT_SET_STRICT((duk_hobject *) h_res);
+ }
+
+ if (func->is_notail) {
+ DUK_DDD(DUK_DDDPRINT("function is notail -> set NOTAIL"));
+ DUK_HOBJECT_SET_NOTAIL((duk_hobject *) h_res);
+ }
+
+ /*
+ * Build function fixed size 'data' buffer, which contains bytecode,
+ * constants, and inner function references.
+ *
+ * During the building phase 'data' is reachable but incomplete.
+ * Only incref's occur during building (no refzero or GC happens),
+ * so the building process is atomic.
+ */
+
+ consts_count = duk_hobject_get_length(thr, func->h_consts);
+ funcs_count = duk_hobject_get_length(thr, func->h_funcs) / 3;
+ code_count = DUK_BW_GET_SIZE(thr, &func->bw_code) / sizeof(duk_compiler_instr);
+ code_size = code_count * sizeof(duk_instr_t);
+
+ data_size = consts_count * sizeof(duk_tval) +
+ funcs_count * sizeof(duk_hobject *) +
+ code_size;
+
+ DUK_DDD(DUK_DDDPRINT("consts_count=%ld, funcs_count=%ld, code_size=%ld -> "
+ "data_size=%ld*%ld + %ld*%ld + %ld = %ld",
+ (long) consts_count, (long) funcs_count, (long) code_size,
+ (long) consts_count, (long) sizeof(duk_tval),
+ (long) funcs_count, (long) sizeof(duk_hobject *),
+ (long) code_size, (long) data_size));
+
+ duk_push_fixed_buffer(ctx, data_size);
+ h_data = (duk_hbuffer_fixed *) duk_get_hbuffer(ctx, -1);
+ DUK_ASSERT(h_data != NULL);
+
+ DUK_HCOMPILEDFUNCTION_SET_DATA(thr->heap, h_res, (duk_hbuffer *) h_data);
+ DUK_HEAPHDR_INCREF(thr, h_data);
+
+ p_const = (duk_tval *) (void *) DUK_HBUFFER_FIXED_GET_DATA_PTR(thr->heap, h_data);
+ for (i = 0; i < consts_count; i++) {
+ DUK_ASSERT(i <= DUK_UARRIDX_MAX); /* const limits */
+ tv = duk_hobject_find_existing_array_entry_tval_ptr(thr->heap, func->h_consts, (duk_uarridx_t) i);
+ DUK_ASSERT(tv != NULL);
+ DUK_TVAL_SET_TVAL(p_const, tv);
+ p_const++;
+ DUK_TVAL_INCREF(thr, tv); /* may be a string constant */
+
+ DUK_DDD(DUK_DDDPRINT("constant: %!T", (duk_tval *) tv));
+ }
+
+ p_func = (duk_hobject **) p_const;
+ DUK_HCOMPILEDFUNCTION_SET_FUNCS(thr->heap, h_res, p_func);
+ for (i = 0; i < funcs_count; i++) {
+ duk_hobject *h;
+ DUK_ASSERT(i * 3 <= DUK_UARRIDX_MAX); /* func limits */
+ tv = duk_hobject_find_existing_array_entry_tval_ptr(thr->heap, func->h_funcs, (duk_uarridx_t) (i * 3));
+ DUK_ASSERT(tv != NULL);
+ DUK_ASSERT(DUK_TVAL_IS_OBJECT(tv));
+ h = DUK_TVAL_GET_OBJECT(tv);
+ DUK_ASSERT(h != NULL);
+ DUK_ASSERT(DUK_HOBJECT_IS_COMPILEDFUNCTION(h));
+ *p_func++ = h;
+ DUK_HOBJECT_INCREF(thr, h);
+
+ DUK_DDD(DUK_DDDPRINT("inner function: %p -> %!iO",
+ (void *) h, (duk_heaphdr *) h));
+ }
+
+ p_instr = (duk_instr_t *) p_func;
+ DUK_HCOMPILEDFUNCTION_SET_BYTECODE(thr->heap, h_res, p_instr);
+
+ /* copy bytecode instructions one at a time */
+ q_instr = (duk_compiler_instr *) (void *) DUK_BW_GET_BASEPTR(thr, &func->bw_code);
+ for (i = 0; i < code_count; i++) {
+ p_instr[i] = q_instr[i].ins;
+ }
+ /* Note: 'q_instr' is still used below */
+
+ DUK_ASSERT((duk_uint8_t *) (p_instr + code_count) == DUK_HBUFFER_FIXED_GET_DATA_PTR(thr->heap, h_data) + data_size);
+
+ duk_pop(ctx); /* 'data' (and everything in it) is reachable through h_res now */
+
+ /*
+ * Init object properties
+ *
+ * Properties should be added in decreasing order of access frequency.
+ * (Not very critical for function templates.)
+ */
+
+ DUK_DDD(DUK_DDDPRINT("init function properties"));
+
+ /* [ ... res ] */
+
+ /* _Varmap: omitted if function is guaranteed not to do slow path identifier
+ * accesses or if it would turn out to be empty of actual register mappings
+ * after a cleanup. When debugging is enabled, we always need the varmap to
+ * be able to lookup variables at any point.
+ */
+#if defined(DUK_USE_DEBUGGER_SUPPORT)
+ if (1) {
+#else
+ if (func->id_access_slow || /* directly uses slow accesses */
+ func->may_direct_eval || /* may indirectly slow access through a direct eval */
+ funcs_count > 0) { /* has inner functions which may slow access (XXX: this can be optimized by looking at the inner functions) */
+#endif
+ duk_int_t num_used;
+ duk_dup(ctx, func->varmap_idx);
+ num_used = duk__cleanup_varmap(comp_ctx);
+ DUK_DDD(DUK_DDDPRINT("cleaned up varmap: %!T (num_used=%ld)",
+ (duk_tval *) duk_get_tval(ctx, -1), (long) num_used));
+
+ if (num_used > 0) {
+ duk_xdef_prop_stridx(ctx, -2, DUK_STRIDX_INT_VARMAP, DUK_PROPDESC_FLAGS_NONE);
+ } else {
+ DUK_DDD(DUK_DDDPRINT("varmap is empty after cleanup -> no need to add"));
+ duk_pop(ctx);
+ }
+ }
+
+ /* _Formals: omitted if function is guaranteed not to need a (non-strict) arguments object */
+ if (1) {
+ /* XXX: Add a proper condition. If formals list is omitted, recheck
+ * handling for 'length' in duk_js_push_closure(); it currently relies
+ * on _Formals being set. Removal may need to be conditional to debugging
+ * being enabled/disabled too.
+ */
+ duk_dup(ctx, func->argnames_idx);
+ duk_xdef_prop_stridx(ctx, -2, DUK_STRIDX_INT_FORMALS, DUK_PROPDESC_FLAGS_NONE);
+ }
+
+ /* name */
+ if (func->h_name) {
+ duk_push_hstring(ctx, func->h_name);
+ duk_xdef_prop_stridx(ctx, -2, DUK_STRIDX_NAME, DUK_PROPDESC_FLAGS_NONE);
+ }
+
+ /* _Source */
+#if defined(DUK_USE_NONSTD_FUNC_SOURCE_PROPERTY)
+ if (0) {
+ /* XXX: Currently function source code is not stored, as it is not
+ * required by the standard. Source code should not be stored by
+ * default (user should enable it explicitly), and the source should
+ * probably be compressed with a trivial text compressor; average
+ * compression of 20-30% is quite easy to achieve even with a trivial
+ * compressor (RLE + backwards lookup).
+ *
+ * Debugging needs source code to be useful: sometimes input code is
+ * not found in files as it may be generated and then eval()'d, given
+ * by dynamic C code, etc.
+ *
+ * Other issues:
+ *
+ * - Need tokenizer indices for start and end to substring
+ * - Always normalize function declaration part?
+ * - If we keep _Formals, only need to store body
+ */
+
+ /*
+ * For global or eval code this is straightforward. For functions
+ * created with the Function constructor we only get the source for
+ * the body and must manufacture the "function ..." part.
+ *
+ * For instance, for constructed functions (v8):
+ *
+ * > a = new Function("foo", "bar", "print(foo)");
+ * [Function]
+ * > a.toString()
+ * 'function anonymous(foo,bar) {\nprint(foo)\n}'
+ *
+ * Similarly for e.g. getters (v8):
+ *
+ * > x = { get a(foo,bar) { print(foo); } }
+ * { a: [Getter] }
+ * > Object.getOwnPropertyDescriptor(x, 'a').get.toString()
+ * 'function a(foo,bar) { print(foo); }'
+ */
+
+#if 0
+ duk_push_string(ctx, "XXX");
+ duk_xdef_prop_stridx(ctx, -2, DUK_STRIDX_INT_SOURCE, DUK_PROPDESC_FLAGS_NONE);
+#endif
+ }
+#endif /* DUK_USE_NONSTD_FUNC_SOURCE_PROPERTY */
+
+ /* _Pc2line */
+#if defined(DUK_USE_PC2LINE)
+ if (1) {
+ /*
+ * Size-optimized pc->line mapping.
+ */
+
+ DUK_ASSERT(code_count <= DUK_COMPILER_MAX_BYTECODE_LENGTH);
+ duk_hobject_pc2line_pack(thr, q_instr, (duk_uint_fast32_t) code_count); /* -> pushes fixed buffer */
+ duk_xdef_prop_stridx(ctx, -2, DUK_STRIDX_INT_PC2LINE, DUK_PROPDESC_FLAGS_NONE);
+
+ /* XXX: if assertions enabled, walk through all valid PCs
+ * and check line mapping.
+ */
+ }
+#endif /* DUK_USE_PC2LINE */
+
+ /* fileName */
+ if (comp_ctx->h_filename) {
+ /*
+ * Source filename (or equivalent), for identifying thrown errors.
+ */
+
+ duk_push_hstring(ctx, comp_ctx->h_filename);
+ duk_xdef_prop_stridx(ctx, -2, DUK_STRIDX_FILE_NAME, DUK_PROPDESC_FLAGS_NONE);
+ }
+
+ /*
+ * Init remaining result fields
+ *
+ * 'nregs' controls how large a register frame is allocated.
+ *
+ * 'nargs' controls how many formal arguments are written to registers:
+ * r0, ... r(nargs-1). The remaining registers are initialized to
+ * undefined.
+ */
+
+ DUK_ASSERT(func->temp_max >= 0);
+ h_res->nregs = (duk_uint16_t) func->temp_max;
+ h_res->nargs = (duk_uint16_t) duk_hobject_get_length(thr, func->h_argnames);
+ DUK_ASSERT(h_res->nregs >= h_res->nargs); /* pass2 allocation handles this */
+#if defined(DUK_USE_DEBUGGER_SUPPORT)
+ h_res->start_line = (duk_uint32_t) func->min_line;
+ h_res->end_line = (duk_uint32_t) func->max_line;
+#endif
+
+ DUK_DD(DUK_DDPRINT("converted function: %!ixT",
+ (duk_tval *) duk_get_tval(ctx, -1)));
+
+ /*
+ * Compact the function template.
+ */
+
+ duk_compact(ctx, -1);
+
+ /*
+ * Debug dumping
+ */
+
+#ifdef DUK_USE_DDDPRINT
+ {
+ duk_hcompiledfunction *h;
+ duk_instr_t *p, *p_start, *p_end;
+
+ h = (duk_hcompiledfunction *) duk_get_hobject(ctx, -1);
+ p_start = (duk_instr_t *) DUK_HCOMPILEDFUNCTION_GET_CODE_BASE(thr->heap, h);
+ p_end = (duk_instr_t *) DUK_HCOMPILEDFUNCTION_GET_CODE_END(thr->heap, h);
+
+ p = p_start;
+ while (p < p_end) {
+ DUK_DDD(DUK_DDDPRINT("BC %04ld: %!I ; 0x%08lx op=%ld (%!C) a=%ld b=%ld c=%ld",
+ (long) (p - p_start),
+ (duk_instr_t) (*p),
+ (unsigned long) (*p),
+ (long) DUK_DEC_OP(*p),
+ (long) DUK_DEC_OP(*p),
+ (long) DUK_DEC_A(*p),
+ (long) DUK_DEC_B(*p),
+ (long) DUK_DEC_C(*p)));
+ p++;
+ }
+ }
+#endif
+}
+
+/*
+ * Code emission helpers
+ *
+ * Some emission helpers understand the range of target and source reg/const
+ * values and automatically emit shuffling code if necessary. This is the
+ * case when the slot in question (A, B, C) is used in the standard way and
+ * for opcodes the emission helpers explicitly understand (like DUK_OP_CALL).
+ *
+ * The standard way is that:
+ * - slot A is a target register
+ * - slot B is a source register/constant
+ * - slot C is a source register/constant
+ *
+ * If a slot is used in a non-standard way the caller must indicate this
+ * somehow. If a slot is used as a target instead of a source (or vice
+ * versa), this can be indicated with a flag to trigger proper shuffling
+ * (e.g. DUK__EMIT_FLAG_B_IS_TARGET). If the value in the slot is not
+ * register/const related at all, the caller must ensure that the raw value
+ * fits into the corresponding slot so as to not trigger shuffling. The
+ * caller must set a "no shuffle" flag to ensure compilation fails if
+ * shuffling were to be triggered because of an internal error.
+ *
+ * For slots B and C the raw slot size is 9 bits but one bit is reserved for
+ * the reg/const indicator. To use the full 9-bit range for a raw value,
+ * shuffling must be disabled with the DUK__EMIT_FLAG_NO_SHUFFLE_{B,C} flag.
+ * Shuffling is only done for A, B, and C slots, not the larger BC or ABC slots.
+ *
+ * There is call handling specific understanding in the A-B-C emitter to
+ * convert call setup and call instructions into indirect ones if necessary.
+ */
+
+/* Code emission flags, passed in the 'opcode' field. Opcode + flags
+ * fit into 16 bits for now, so use duk_small_uint.t.
+ */
+#define DUK__EMIT_FLAG_NO_SHUFFLE_A (1 << 8)
+#define DUK__EMIT_FLAG_NO_SHUFFLE_B (1 << 9)
+#define DUK__EMIT_FLAG_NO_SHUFFLE_C (1 << 10)
+#define DUK__EMIT_FLAG_A_IS_SOURCE (1 << 11) /* slot A is a source (default: target) */
+#define DUK__EMIT_FLAG_B_IS_TARGET (1 << 12) /* slot B is a target (default: source) */
+#define DUK__EMIT_FLAG_C_IS_TARGET (1 << 13) /* slot C is a target (default: source) */
+#define DUK__EMIT_FLAG_B_IS_TARGETSOURCE (1 << 14) /* slot B is both a target and a source (used by extraops like DUK_EXTRAOP_INSTOF */
+#define DUK__EMIT_FLAG_RESERVE_JUMPSLOT (1 << 15) /* reserve a jumpslot after instr before target spilling, used for NEXTENUM */
+
+/* XXX: clarify on when and where DUK__CONST_MARKER is allowed */
+/* XXX: opcode specific assertions on when consts are allowed */
+
+/* XXX: macro smaller than call? */
+DUK_LOCAL duk_int_t duk__get_current_pc(duk_compiler_ctx *comp_ctx) {
+ duk_compiler_func *func;
+ func = &comp_ctx->curr_func;
+ return (duk_int_t) (DUK_BW_GET_SIZE(comp_ctx->thr, &func->bw_code) / sizeof(duk_compiler_instr));
+}
+
+DUK_LOCAL duk_compiler_instr *duk__get_instr_ptr(duk_compiler_ctx *comp_ctx, duk_int_t pc) {
+ DUK_ASSERT(pc >= 0);
+ DUK_ASSERT((duk_size_t) pc < (duk_size_t) (DUK_BW_GET_SIZE(comp_ctx->thr, &comp_ctx->curr_func.bw_code) / sizeof(duk_compiler_instr)));
+ return ((duk_compiler_instr *) (void *) DUK_BW_GET_BASEPTR(comp_ctx->thr, &comp_ctx->curr_func.bw_code)) + pc;
+}
+
+/* emit instruction; could return PC but that's not needed in the majority
+ * of cases.
+ */
+DUK_LOCAL void duk__emit(duk_compiler_ctx *comp_ctx, duk_instr_t ins) {
+#if defined(DUK_USE_PC2LINE)
+ duk_int_t line;
+#endif
+ duk_compiler_instr *instr;
+
+ DUK_DDD(DUK_DDDPRINT("duk__emit: 0x%08lx curr_token.start_line=%ld prev_token.start_line=%ld pc=%ld --> %!I",
+ (unsigned long) ins,
+ (long) comp_ctx->curr_token.start_line,
+ (long) comp_ctx->prev_token.start_line,
+ (long) duk__get_current_pc(comp_ctx),
+ (duk_instr_t) ins));
+
+ instr = (duk_compiler_instr *) (void *) DUK_BW_ENSURE_GETPTR(comp_ctx->thr, &comp_ctx->curr_func.bw_code, sizeof(duk_compiler_instr));
+ DUK_BW_ADD_PTR(comp_ctx->thr, &comp_ctx->curr_func.bw_code, sizeof(duk_compiler_instr));
+
+#if defined(DUK_USE_PC2LINE)
+ /* The line number tracking is a bit inconsistent right now, which
+ * affects debugger accuracy. Mostly call sites emit opcodes when
+ * they have parsed a token (say a terminating semicolon) and called
+ * duk__advance(). In this case the line number of the previous
+ * token is the most accurate one (except in prologue where
+ * prev_token.start_line is 0). This is probably not 100% correct
+ * right now.
+ */
+ /* approximation, close enough */
+ line = comp_ctx->prev_token.start_line;
+ if (line == 0) {
+ line = comp_ctx->curr_token.start_line;
+ }
+#endif
+
+ instr->ins = ins;
+#if defined(DUK_USE_PC2LINE)
+ instr->line = line;
+#endif
+#if defined(DUK_USE_DEBUGGER_SUPPORT)
+ if (line < comp_ctx->curr_func.min_line) {
+ comp_ctx->curr_func.min_line = line;
+ }
+ if (line > comp_ctx->curr_func.max_line) {
+ comp_ctx->curr_func.max_line = line;
+ }
+#endif
+
+ /* Limit checks for bytecode byte size and line number. */
+ if (DUK_UNLIKELY(DUK_BW_GET_SIZE(comp_ctx->thr, &comp_ctx->curr_func.bw_code) > DUK_USE_ESBC_MAX_BYTES)) {
+ goto fail_bc_limit;
+ }
+#if defined(DUK_USE_PC2LINE) && defined(DUK_USE_ESBC_LIMITS)
+#if defined(DUK_USE_BUFLEN16)
+ /* Buffer length is bounded to 0xffff automatically, avoid compile warning. */
+ if (DUK_UNLIKELY(line > DUK_USE_ESBC_MAX_LINENUMBER)) {
+ goto fail_bc_limit;
+ }
+#else
+ if (DUK_UNLIKELY(line > DUK_USE_ESBC_MAX_LINENUMBER)) {
+ goto fail_bc_limit;
+ }
+#endif
+#endif
+
+ return;
+
+ fail_bc_limit:
+ DUK_ERROR_RANGE(comp_ctx->thr, DUK_STR_BYTECODE_LIMIT);
+}
+
+/* Update function min/max line from current token. Needed to improve
+ * function line range information for debugging, so that e.g. opening
+ * curly brace is covered by line range even when no opcodes are emitted
+ * for the line containing the brace.
+ */
+DUK_LOCAL void duk__update_lineinfo_currtoken(duk_compiler_ctx *comp_ctx) {
+#if defined(DUK_USE_DEBUGGER_SUPPORT)
+ duk_int_t line;
+
+ line = comp_ctx->curr_token.start_line;
+ if (line == 0) {
+ return;
+ }
+ if (line < comp_ctx->curr_func.min_line) {
+ comp_ctx->curr_func.min_line = line;
+ }
+ if (line > comp_ctx->curr_func.max_line) {
+ comp_ctx->curr_func.max_line = line;
+ }
+#else
+ DUK_UNREF(comp_ctx);
+#endif
+}
+
+#if 0 /* unused */
+DUK_LOCAL void duk__emit_op_only(duk_compiler_ctx *comp_ctx, duk_small_uint_t op) {
+ duk__emit(comp_ctx, DUK_ENC_OP_ABC(op, 0));
+}
+#endif
+
+/* Important main primitive. */
+DUK_LOCAL void duk__emit_a_b_c(duk_compiler_ctx *comp_ctx, duk_small_uint_t op_flags, duk_regconst_t a, duk_regconst_t b, duk_regconst_t c) {
+ duk_instr_t ins = 0;
+ duk_int_t a_out = -1;
+ duk_int_t b_out = -1;
+ duk_int_t c_out = -1;
+ duk_int_t tmp;
+
+ DUK_DDD(DUK_DDDPRINT("emit: op_flags=%04lx, a=%ld, b=%ld, c=%ld",
+ (unsigned long) op_flags, (long) a, (long) b, (long) c));
+
+ /* We could rely on max temp/const checks: if they don't exceed BC
+ * limit, nothing here can either (just asserts would be enough).
+ * Currently we check for the limits, which provides additional
+ * protection against creating invalid bytecode due to compiler
+ * bugs.
+ */
+
+ DUK_ASSERT_DISABLE((op_flags & 0xff) >= DUK_BC_OP_MIN); /* unsigned */
+ DUK_ASSERT((op_flags & 0xff) <= DUK_BC_OP_MAX);
+
+ /* Input shuffling happens before the actual operation, while output
+ * shuffling happens afterwards. Output shuffling decisions are still
+ * made at the same time to reduce branch clutter; output shuffle decisions
+ * are recorded into X_out variables.
+ */
+
+ /* Slot A */
+
+#if defined(DUK_USE_SHUFFLE_TORTURE)
+ if (a <= DUK_BC_A_MAX && (op_flags & DUK__EMIT_FLAG_NO_SHUFFLE_A)) {
+#else
+ if (a <= DUK_BC_A_MAX) {
+#endif
+ ;
+ } else if (op_flags & DUK__EMIT_FLAG_NO_SHUFFLE_A) {
+ DUK_D(DUK_DPRINT("out of regs: 'a' (reg) needs shuffling but shuffle prohibited, a: %ld", (long) a));
+ goto error_outofregs;
+ } else if (a <= DUK_BC_BC_MAX) {
+ comp_ctx->curr_func.needs_shuffle = 1;
+ tmp = comp_ctx->curr_func.shuffle1;
+ if (op_flags & DUK__EMIT_FLAG_A_IS_SOURCE) {
+ duk__emit(comp_ctx, DUK_ENC_OP_A_BC(DUK_OP_LDREG, tmp, a));
+ } else {
+ duk_small_int_t op = op_flags & 0xff;
+ if (op == DUK_OP_CSVAR || op == DUK_OP_CSREG || op == DUK_OP_CSPROP) {
+ /* Special handling for call setup instructions. The target
+ * is expressed indirectly, but there is no output shuffling.
+ */
+ DUK_ASSERT((op_flags & DUK__EMIT_FLAG_A_IS_SOURCE) == 0);
+ duk__emit_load_int32_noshuffle(comp_ctx, tmp, a);
+ DUK_ASSERT(DUK_OP_CSVARI == DUK_OP_CSVAR + 1);
+ DUK_ASSERT(DUK_OP_CSREGI == DUK_OP_CSREG + 1);
+ DUK_ASSERT(DUK_OP_CSPROPI == DUK_OP_CSPROP + 1);
+ op_flags++; /* indirect opcode follows direct */
+ } else {
+ /* Output shuffle needed after main operation */
+ a_out = a;
+ }
+ }
+ a = tmp;
+ } else {
+ DUK_D(DUK_DPRINT("out of regs: 'a' (reg) needs shuffling but does not fit into BC, a: %ld", (long) a));
+ goto error_outofregs;
+ }
+
+ /* Slot B */
+
+ if (b & DUK__CONST_MARKER) {
+ DUK_ASSERT((op_flags & DUK__EMIT_FLAG_NO_SHUFFLE_B) == 0);
+ DUK_ASSERT((op_flags & DUK__EMIT_FLAG_B_IS_TARGET) == 0);
+ DUK_ASSERT((op_flags & 0xff) != DUK_OP_CALL);
+ DUK_ASSERT((op_flags & 0xff) != DUK_OP_NEW);
+ b = b & ~DUK__CONST_MARKER;
+#if defined(DUK_USE_SHUFFLE_TORTURE)
+ if (0) {
+#else
+ if (b <= 0xff) {
+#endif
+ ins |= DUK_ENC_OP_A_B_C(0, 0, 0x100, 0); /* const flag for B */
+ } else if (b <= DUK_BC_BC_MAX) {
+ comp_ctx->curr_func.needs_shuffle = 1;
+ tmp = comp_ctx->curr_func.shuffle2;
+ duk__emit(comp_ctx, DUK_ENC_OP_A_BC(DUK_OP_LDCONST, tmp, b));
+ b = tmp;
+ } else {
+ DUK_D(DUK_DPRINT("out of regs: 'b' (const) needs shuffling but does not fit into BC, b: %ld", (long) b));
+ goto error_outofregs;
+ }
+ } else {
+#if defined(DUK_USE_SHUFFLE_TORTURE)
+ if (b <= 0xff && (op_flags & DUK__EMIT_FLAG_NO_SHUFFLE_B)) {
+#else
+ if (b <= 0xff) {
+#endif
+ ;
+ } else if (op_flags & DUK__EMIT_FLAG_NO_SHUFFLE_B) {
+ if (b > DUK_BC_B_MAX) {
+ /* Note: 0xff != DUK_BC_B_MAX */
+ DUK_D(DUK_DPRINT("out of regs: 'b' (reg) needs shuffling but shuffle prohibited, b: %ld", (long) b));
+ goto error_outofregs;
+ }
+ } else if (b <= DUK_BC_BC_MAX) {
+ comp_ctx->curr_func.needs_shuffle = 1;
+ tmp = comp_ctx->curr_func.shuffle2;
+ if (op_flags & DUK__EMIT_FLAG_B_IS_TARGET) {
+ /* Output shuffle needed after main operation */
+ b_out = b;
+ }
+ if (!(op_flags & DUK__EMIT_FLAG_B_IS_TARGET) || (op_flags & DUK__EMIT_FLAG_B_IS_TARGETSOURCE)) {
+ duk_small_int_t op = op_flags & 0xff;
+ if (op == DUK_OP_CALL || op == DUK_OP_NEW ||
+ op == DUK_OP_MPUTOBJ || op == DUK_OP_MPUTARR) {
+ /* Special handling for CALL/NEW/MPUTOBJ/MPUTARR shuffling.
+ * For each, slot B identifies the first register of a range
+ * of registers, so normal shuffling won't work. Instead,
+ * an indirect version of the opcode is used.
+ */
+ DUK_ASSERT((op_flags & DUK__EMIT_FLAG_B_IS_TARGET) == 0);
+ duk__emit_load_int32_noshuffle(comp_ctx, tmp, b);
+ DUK_ASSERT(DUK_OP_CALLI == DUK_OP_CALL + 1);
+ DUK_ASSERT(DUK_OP_NEWI == DUK_OP_NEW + 1);
+ DUK_ASSERT(DUK_OP_MPUTOBJI == DUK_OP_MPUTOBJ + 1);
+ DUK_ASSERT(DUK_OP_MPUTARRI == DUK_OP_MPUTARR + 1);
+ op_flags++; /* indirect opcode follows direct */
+ } else {
+ duk__emit(comp_ctx, DUK_ENC_OP_A_BC(DUK_OP_LDREG, tmp, b));
+ }
+ }
+ b = tmp;
+ } else {
+ DUK_D(DUK_DPRINT("out of regs: 'b' (reg) needs shuffling but does not fit into BC, b: %ld", (long) b));
+ goto error_outofregs;
+ }
+ }
+
+ /* Slot C */
+
+ if (c & DUK__CONST_MARKER) {
+ DUK_ASSERT((op_flags & DUK__EMIT_FLAG_NO_SHUFFLE_C) == 0);
+ DUK_ASSERT((op_flags & DUK__EMIT_FLAG_C_IS_TARGET) == 0);
+ c = c & ~DUK__CONST_MARKER;
+#if defined(DUK_USE_SHUFFLE_TORTURE)
+ if (0) {
+#else
+ if (c <= 0xff) {
+#endif
+ ins |= DUK_ENC_OP_A_B_C(0, 0, 0, 0x100); /* const flag for C */
+ } else if (c <= DUK_BC_BC_MAX) {
+ comp_ctx->curr_func.needs_shuffle = 1;
+ tmp = comp_ctx->curr_func.shuffle3;
+ duk__emit(comp_ctx, DUK_ENC_OP_A_BC(DUK_OP_LDCONST, tmp, c));
+ c = tmp;
+ } else {
+ DUK_D(DUK_DPRINT("out of regs: 'c' (const) needs shuffling but does not fit into BC, c: %ld", (long) c));
+ goto error_outofregs;
+ }
+ } else {
+#if defined(DUK_USE_SHUFFLE_TORTURE)
+ if (c <= 0xff && (op_flags & DUK__EMIT_FLAG_NO_SHUFFLE_C)) {
+#else
+ if (c <= 0xff) {
+#endif
+ ;
+ } else if (op_flags & DUK__EMIT_FLAG_NO_SHUFFLE_C) {
+ if (c > DUK_BC_C_MAX) {
+ /* Note: 0xff != DUK_BC_C_MAX */
+ DUK_D(DUK_DPRINT("out of regs: 'c' (reg) needs shuffling but shuffle prohibited, c: %ld", (long) c));
+ goto error_outofregs;
+ }
+ } else if (c <= DUK_BC_BC_MAX) {
+ comp_ctx->curr_func.needs_shuffle = 1;
+ tmp = comp_ctx->curr_func.shuffle3;
+ if (op_flags & DUK__EMIT_FLAG_C_IS_TARGET) {
+ /* Output shuffle needed after main operation */
+ c_out = c;
+ } else {
+ duk_small_int_t op = op_flags & 0xff;
+ if (op == DUK_OP_EXTRA &&
+ (a == DUK_EXTRAOP_INITGET || a == DUK_EXTRAOP_INITSET)) {
+ /* Special shuffling for INITGET/INITSET, where slot C
+ * identifies a register pair and cannot be shuffled
+ * normally. Use an indirect variant instead.
+ */
+ DUK_ASSERT((op_flags & DUK__EMIT_FLAG_C_IS_TARGET) == 0);
+ duk__emit_load_int32_noshuffle(comp_ctx, tmp, c);
+ DUK_ASSERT(DUK_EXTRAOP_INITGETI == DUK_EXTRAOP_INITGET + 1);
+ DUK_ASSERT(DUK_EXTRAOP_INITSETI == DUK_EXTRAOP_INITSET + 1);
+ a++; /* indirect opcode follows direct */
+ } else {
+ duk__emit(comp_ctx, DUK_ENC_OP_A_BC(DUK_OP_LDREG, tmp, c));
+ }
+ }
+ c = tmp;
+ } else {
+ DUK_D(DUK_DPRINT("out of regs: 'c' (reg) needs shuffling but does not fit into BC, c: %ld", (long) c));
+ goto error_outofregs;
+ }
+ }
+
+ /* Main operation */
+
+ DUK_ASSERT_DISABLE(a >= DUK_BC_A_MIN); /* unsigned */
+ DUK_ASSERT(a <= DUK_BC_A_MAX);
+ DUK_ASSERT_DISABLE(b >= DUK_BC_B_MIN); /* unsigned */
+ DUK_ASSERT(b <= DUK_BC_B_MAX);
+ DUK_ASSERT_DISABLE(c >= DUK_BC_C_MIN); /* unsigned */
+ DUK_ASSERT(c <= DUK_BC_C_MAX);
+
+ ins |= DUK_ENC_OP_A_B_C(op_flags & 0xff, a, b, c);
+ duk__emit(comp_ctx, ins);
+
+ /* NEXTENUM needs a jump slot right after the main instruction.
+ * When the JUMP is taken, output spilling is not needed so this
+ * workaround is possible. The jump slot PC is exceptionally
+ * plumbed through comp_ctx to minimize call sites.
+ */
+ if (op_flags & DUK__EMIT_FLAG_RESERVE_JUMPSLOT) {
+ comp_ctx->emit_jumpslot_pc = duk__get_current_pc(comp_ctx);
+ duk__emit_abc(comp_ctx, DUK_OP_JUMP, 0);
+ }
+
+ /* Output shuffling: only one output register is realistically possible.
+ *
+ * (Zero would normally be an OK marker value: if the target register
+ * was zero, it would never be shuffled. But with DUK_USE_SHUFFLE_TORTURE
+ * this is no longer true, so use -1 as a marker instead.)
+ */
+
+ if (a_out >= 0) {
+ DUK_ASSERT(b_out < 0);
+ DUK_ASSERT(c_out < 0);
+ duk__emit(comp_ctx, DUK_ENC_OP_A_BC(DUK_OP_STREG, a, a_out));
+ } else if (b_out >= 0) {
+ DUK_ASSERT(a_out < 0);
+ DUK_ASSERT(c_out < 0);
+ duk__emit(comp_ctx, DUK_ENC_OP_A_BC(DUK_OP_STREG, b, b_out));
+ } else if (c_out >= 0) {
+ DUK_ASSERT(b_out < 0);
+ DUK_ASSERT(c_out < 0);
+ duk__emit(comp_ctx, DUK_ENC_OP_A_BC(DUK_OP_STREG, c, c_out));
+ }
+
+ return;
+
+ error_outofregs:
+ DUK_ERROR_RANGE(comp_ctx->thr, DUK_STR_REG_LIMIT);
+}
+
+DUK_LOCAL void duk__emit_a_b(duk_compiler_ctx *comp_ctx, duk_small_uint_t op_flags, duk_regconst_t a, duk_regconst_t b) {
+ duk__emit_a_b_c(comp_ctx, op_flags | DUK__EMIT_FLAG_NO_SHUFFLE_C, a, b, 0);
+}
+
+#if 0 /* unused */
+DUK_LOCAL void duk__emit_a(duk_compiler_ctx *comp_ctx, int op_flags, int a) {
+ duk__emit_a_b_c(comp_ctx, op_flags | DUK__EMIT_FLAG_NO_SHUFFLE_B | DUK__EMIT_FLAG_NO_SHUFFLE_C, a, 0, 0);
+}
+#endif
+
+DUK_LOCAL void duk__emit_a_bc(duk_compiler_ctx *comp_ctx, duk_small_uint_t op_flags, duk_regconst_t a, duk_regconst_t bc) {
+ duk_instr_t ins;
+ duk_int_t tmp;
+
+ /* allow caller to give a const number with the DUK__CONST_MARKER */
+ bc = bc & (~DUK__CONST_MARKER);
+
+ DUK_ASSERT_DISABLE((op_flags & 0xff) >= DUK_BC_OP_MIN); /* unsigned */
+ DUK_ASSERT((op_flags & 0xff) <= DUK_BC_OP_MAX);
+ DUK_ASSERT_DISABLE(bc >= DUK_BC_BC_MIN); /* unsigned */
+ DUK_ASSERT(bc <= DUK_BC_BC_MAX);
+ DUK_ASSERT((bc & DUK__CONST_MARKER) == 0);
+
+ if (bc <= DUK_BC_BC_MAX) {
+ ;
+ } else {
+ /* No BC shuffling now. */
+ goto error_outofregs;
+ }
+
+#if defined(DUK_USE_SHUFFLE_TORTURE)
+ if (a <= DUK_BC_A_MAX && (op_flags & DUK__EMIT_FLAG_NO_SHUFFLE_A)) {
+#else
+ if (a <= DUK_BC_A_MAX) {
+#endif
+ ins = DUK_ENC_OP_A_BC(op_flags & 0xff, a, bc);
+ duk__emit(comp_ctx, ins);
+ } else if (op_flags & DUK__EMIT_FLAG_NO_SHUFFLE_A) {
+ goto error_outofregs;
+ } else if (a <= DUK_BC_BC_MAX) {
+ comp_ctx->curr_func.needs_shuffle = 1;
+ tmp = comp_ctx->curr_func.shuffle1;
+ ins = DUK_ENC_OP_A_BC(op_flags & 0xff, tmp, bc);
+ if (op_flags & DUK__EMIT_FLAG_A_IS_SOURCE) {
+ duk__emit(comp_ctx, DUK_ENC_OP_A_BC(DUK_OP_LDREG, tmp, a));
+ duk__emit(comp_ctx, ins);
+ } else {
+ duk__emit(comp_ctx, ins);
+ duk__emit(comp_ctx, DUK_ENC_OP_A_BC(DUK_OP_STREG, tmp, a));
+ }
+ } else {
+ goto error_outofregs;
+ }
+ return;
+
+ error_outofregs:
+ DUK_ERROR_RANGE(comp_ctx->thr, DUK_STR_REG_LIMIT);
+}
+
+DUK_LOCAL void duk__emit_abc(duk_compiler_ctx *comp_ctx, duk_small_uint_t op, duk_regconst_t abc) {
+ duk_instr_t ins;
+
+ DUK_ASSERT_DISABLE(op >= DUK_BC_OP_MIN); /* unsigned */
+ DUK_ASSERT(op <= DUK_BC_OP_MAX);
+ DUK_ASSERT_DISABLE(abc >= DUK_BC_ABC_MIN); /* unsigned */
+ DUK_ASSERT(abc <= DUK_BC_ABC_MAX);
+ DUK_ASSERT((abc & DUK__CONST_MARKER) == 0);
+
+ if (abc <= DUK_BC_ABC_MAX) {
+ ;
+ } else {
+ goto error_outofregs;
+ }
+ ins = DUK_ENC_OP_ABC(op, abc);
+ DUK_DDD(DUK_DDDPRINT("duk__emit_abc: 0x%08lx line=%ld pc=%ld op=%ld (%!C) abc=%ld (%!I)",
+ (unsigned long) ins, (long) comp_ctx->curr_token.start_line,
+ (long) duk__get_current_pc(comp_ctx), (long) op, (long) op,
+ (long) abc, (duk_instr_t) ins));
+ duk__emit(comp_ctx, ins);
+ return;
+
+ error_outofregs:
+ DUK_ERROR_RANGE(comp_ctx->thr, DUK_STR_REG_LIMIT);
+}
+
+DUK_LOCAL void duk__emit_extraop_b_c(duk_compiler_ctx *comp_ctx, duk_small_uint_t extraop_flags, duk_regconst_t b, duk_regconst_t c) {
+ DUK_ASSERT_DISABLE((extraop_flags & 0xff) >= DUK_BC_EXTRAOP_MIN); /* unsigned */
+ DUK_ASSERT((extraop_flags & 0xff) <= DUK_BC_EXTRAOP_MAX);
+ /* Setting "no shuffle A" is covered by the assert, but it's needed
+ * with DUK_USE_SHUFFLE_TORTURE.
+ */
+ duk__emit_a_b_c(comp_ctx,
+ DUK_OP_EXTRA | DUK__EMIT_FLAG_NO_SHUFFLE_A | (extraop_flags & ~0xff), /* transfer flags */
+ extraop_flags & 0xff,
+ b,
+ c);
+}
+
+DUK_LOCAL void duk__emit_extraop_b(duk_compiler_ctx *comp_ctx, duk_small_uint_t extraop_flags, duk_regconst_t b) {
+ DUK_ASSERT_DISABLE((extraop_flags & 0xff) >= DUK_BC_EXTRAOP_MIN); /* unsigned */
+ DUK_ASSERT((extraop_flags & 0xff) <= DUK_BC_EXTRAOP_MAX);
+ /* Setting "no shuffle A" is covered by the assert, but it's needed
+ * with DUK_USE_SHUFFLE_TORTURE.
+ */
+ duk__emit_a_b_c(comp_ctx,
+ DUK_OP_EXTRA | DUK__EMIT_FLAG_NO_SHUFFLE_A | (extraop_flags & ~0xff), /* transfer flags */
+ extraop_flags & 0xff,
+ b,
+ 0);
+}
+
+DUK_LOCAL void duk__emit_extraop_bc(duk_compiler_ctx *comp_ctx, duk_small_uint_t extraop, duk_regconst_t bc) {
+ DUK_ASSERT_DISABLE(extraop >= DUK_BC_EXTRAOP_MIN); /* unsigned */
+ DUK_ASSERT(extraop <= DUK_BC_EXTRAOP_MAX);
+ /* Setting "no shuffle A" is covered by the assert, but it's needed
+ * with DUK_USE_SHUFFLE_TORTURE.
+ */
+ duk__emit_a_bc(comp_ctx,
+ DUK_OP_EXTRA | DUK__EMIT_FLAG_NO_SHUFFLE_A,
+ extraop,
+ bc);
+}
+
+DUK_LOCAL void duk__emit_extraop_only(duk_compiler_ctx *comp_ctx, duk_small_uint_t extraop_flags) {
+ DUK_ASSERT_DISABLE((extraop_flags & 0xff) >= DUK_BC_EXTRAOP_MIN); /* unsigned */
+ DUK_ASSERT((extraop_flags & 0xff) <= DUK_BC_EXTRAOP_MAX);
+ /* Setting "no shuffle A" is covered by the assert, but it's needed
+ * with DUK_USE_SHUFFLE_TORTURE.
+ */
+ duk__emit_a_b_c(comp_ctx,
+ DUK_OP_EXTRA | DUK__EMIT_FLAG_NO_SHUFFLE_A | DUK__EMIT_FLAG_NO_SHUFFLE_B |
+ DUK__EMIT_FLAG_NO_SHUFFLE_C | (extraop_flags & ~0xff), /* transfer flags */
+ extraop_flags & 0xff,
+ 0,
+ 0);
+}
+
+DUK_LOCAL void duk__emit_load_int32_raw(duk_compiler_ctx *comp_ctx, duk_reg_t reg, duk_int32_t val, duk_small_uint_t op_flags) {
+ /* XXX: Shuffling support could be implemented here so that LDINT+LDINTX
+ * would only shuffle once (instead of twice). The current code works
+ * though, and has a smaller compiler footprint.
+ */
+
+ if ((val >= (duk_int32_t) DUK_BC_BC_MIN - (duk_int32_t) DUK_BC_LDINT_BIAS) &&
+ (val <= (duk_int32_t) DUK_BC_BC_MAX - (duk_int32_t) DUK_BC_LDINT_BIAS)) {
+ DUK_DDD(DUK_DDDPRINT("emit LDINT to reg %ld for %ld", (long) reg, (long) val));
+ duk__emit_a_bc(comp_ctx, DUK_OP_LDINT | op_flags, reg, (duk_regconst_t) (val + (duk_int32_t) DUK_BC_LDINT_BIAS));
+ } else {
+ duk_int32_t hi = val >> DUK_BC_LDINTX_SHIFT;
+ duk_int32_t lo = val & ((((duk_int32_t) 1) << DUK_BC_LDINTX_SHIFT) - 1);
+ DUK_ASSERT(lo >= 0);
+ DUK_DDD(DUK_DDDPRINT("emit LDINT+LDINTX to reg %ld for %ld -> hi %ld, lo %ld",
+ (long) reg, (long) val, (long) hi, (long) lo));
+ duk__emit_a_bc(comp_ctx, DUK_OP_LDINT | op_flags, reg, (duk_regconst_t) (hi + (duk_int32_t) DUK_BC_LDINT_BIAS));
+ duk__emit_a_bc(comp_ctx, DUK_OP_LDINTX | op_flags, reg, (duk_regconst_t) lo);
+ }
+}
+
+DUK_LOCAL void duk__emit_load_int32(duk_compiler_ctx *comp_ctx, duk_reg_t reg, duk_int32_t val) {
+ duk__emit_load_int32_raw(comp_ctx, reg, val, 0 /*op_flags*/);
+}
+
+#if defined(DUK_USE_SHUFFLE_TORTURE)
+/* Used by duk__emit*() calls so that we don't shuffle the loadints that
+ * are needed to handle indirect opcodes.
+ */
+DUK_LOCAL void duk__emit_load_int32_noshuffle(duk_compiler_ctx *comp_ctx, duk_reg_t reg, duk_int32_t val) {
+ duk__emit_load_int32_raw(comp_ctx, reg, val, DUK__EMIT_FLAG_NO_SHUFFLE_A /*op_flags*/);
+}
+#else
+DUK_LOCAL void duk__emit_load_int32_noshuffle(duk_compiler_ctx *comp_ctx, duk_reg_t reg, duk_int32_t val) {
+ /* When torture not enabled, can just use the same helper because
+ * 'reg' won't get spilled.
+ */
+ DUK_ASSERT(reg <= DUK_BC_A_MAX);
+ duk__emit_load_int32(comp_ctx, reg, val);
+}
+#endif
+
+DUK_LOCAL void duk__emit_jump(duk_compiler_ctx *comp_ctx, duk_int_t target_pc) {
+ duk_int_t curr_pc;
+ duk_int_t offset;
+
+ curr_pc = (duk_int_t) (DUK_BW_GET_SIZE(comp_ctx->thr, &comp_ctx->curr_func.bw_code) / sizeof(duk_compiler_instr));
+ offset = (duk_int_t) target_pc - (duk_int_t) curr_pc - 1;
+ DUK_ASSERT(offset + DUK_BC_JUMP_BIAS >= DUK_BC_ABC_MIN);
+ DUK_ASSERT(offset + DUK_BC_JUMP_BIAS <= DUK_BC_ABC_MAX);
+ duk__emit_abc(comp_ctx, DUK_OP_JUMP, (duk_regconst_t) (offset + DUK_BC_JUMP_BIAS));
+}
+
+DUK_LOCAL duk_int_t duk__emit_jump_empty(duk_compiler_ctx *comp_ctx) {
+ duk_int_t ret;
+
+ ret = duk__get_current_pc(comp_ctx); /* useful for patching jumps later */
+ duk__emit_abc(comp_ctx, DUK_OP_JUMP, 0);
+ return ret;
+}
+
+/* Insert an empty jump in the middle of code emitted earlier. This is
+ * currently needed for compiling for-in.
+ */
+DUK_LOCAL void duk__insert_jump_entry(duk_compiler_ctx *comp_ctx, duk_int_t jump_pc) {
+#if defined(DUK_USE_PC2LINE)
+ duk_int_t line;
+#endif
+ duk_compiler_instr *instr;
+ duk_size_t offset;
+
+ offset = jump_pc * sizeof(duk_compiler_instr),
+ instr = (duk_compiler_instr *) (void *)
+ DUK_BW_INSERT_ENSURE_AREA(comp_ctx->thr,
+ &comp_ctx->curr_func.bw_code,
+ offset,
+ sizeof(duk_compiler_instr));
+
+#if defined(DUK_USE_PC2LINE)
+ line = comp_ctx->curr_token.start_line; /* approximation, close enough */
+#endif
+ instr->ins = DUK_ENC_OP_ABC(DUK_OP_JUMP, 0);
+#if defined(DUK_USE_PC2LINE)
+ instr->line = line;
+#endif
+
+ DUK_BW_ADD_PTR(comp_ctx->thr, &comp_ctx->curr_func.bw_code, sizeof(duk_compiler_instr));
+ if (DUK_UNLIKELY(DUK_BW_GET_SIZE(comp_ctx->thr, &comp_ctx->curr_func.bw_code) > DUK_USE_ESBC_MAX_BYTES)) {
+ goto fail_bc_limit;
+ }
+ return;
+
+ fail_bc_limit:
+ DUK_ERROR_RANGE(comp_ctx->thr, DUK_STR_BYTECODE_LIMIT);
+}
+
+/* Does not assume that jump_pc contains a DUK_OP_JUMP previously; this is intentional
+ * to allow e.g. an INVALID opcode be overwritten with a JUMP (label management uses this).
+ */
+DUK_LOCAL void duk__patch_jump(duk_compiler_ctx *comp_ctx, duk_int_t jump_pc, duk_int_t target_pc) {
+ duk_compiler_instr *instr;
+ duk_int_t offset;
+
+ /* allow negative PCs, behave as a no-op */
+ if (jump_pc < 0) {
+ DUK_DDD(DUK_DDDPRINT("duk__patch_jump(): nop call, jump_pc=%ld (<0), target_pc=%ld",
+ (long) jump_pc, (long) target_pc));
+ return;
+ }
+ DUK_ASSERT(jump_pc >= 0);
+
+ /* XXX: range assert */
+ instr = duk__get_instr_ptr(comp_ctx, jump_pc);
+ DUK_ASSERT(instr != NULL);
+
+ /* XXX: range assert */
+ offset = target_pc - jump_pc - 1;
+
+ instr->ins = DUK_ENC_OP_ABC(DUK_OP_JUMP, offset + DUK_BC_JUMP_BIAS);
+ DUK_DDD(DUK_DDDPRINT("duk__patch_jump(): jump_pc=%ld, target_pc=%ld, offset=%ld",
+ (long) jump_pc, (long) target_pc, (long) offset));
+}
+
+DUK_LOCAL void duk__patch_jump_here(duk_compiler_ctx *comp_ctx, duk_int_t jump_pc) {
+ duk__patch_jump(comp_ctx, jump_pc, duk__get_current_pc(comp_ctx));
+}
+
+DUK_LOCAL void duk__patch_trycatch(duk_compiler_ctx *comp_ctx, duk_int_t ldconst_pc, duk_int_t trycatch_pc, duk_regconst_t reg_catch, duk_regconst_t const_varname, duk_small_uint_t flags) {
+ duk_compiler_instr *instr;
+
+ DUK_ASSERT((reg_catch & DUK__CONST_MARKER) == 0);
+
+ instr = duk__get_instr_ptr(comp_ctx, ldconst_pc);
+ DUK_ASSERT(DUK_DEC_OP(instr->ins) == DUK_OP_LDCONST);
+ DUK_ASSERT(instr != NULL);
+ if (const_varname & DUK__CONST_MARKER) {
+ /* Have a catch variable. */
+ const_varname = const_varname & (~DUK__CONST_MARKER);
+ if (reg_catch > DUK_BC_BC_MAX || const_varname > DUK_BC_BC_MAX) {
+ /* Catch attempts to use out-of-range reg/const. Without this
+ * check Duktape 0.12.0 could generate invalid code which caused
+ * an assert failure on execution. This error is triggered e.g.
+ * for functions with a lot of constants and a try-catch statement.
+ * Shuffling or opcode semantics change is needed to fix the issue.
+ * See: test-bug-trycatch-many-constants.js.
+ */
+ DUK_D(DUK_DPRINT("failed to patch trycatch: flags=%ld, reg_catch=%ld, const_varname=%ld (0x%08lx)",
+ (long) flags, (long) reg_catch, (long) const_varname, (long) const_varname));
+ DUK_ERROR_RANGE(comp_ctx->thr, DUK_STR_REG_LIMIT);
+ }
+ instr->ins |= DUK_ENC_OP_A_BC(0, 0, const_varname);
+ } else {
+ /* No catch variable, e.g. a try-finally; replace LDCONST with
+ * NOP to avoid a bogus LDCONST.
+ */
+ instr->ins = DUK_ENC_OP_A(DUK_OP_EXTRA, DUK_EXTRAOP_NOP);
+ }
+
+ instr = duk__get_instr_ptr(comp_ctx, trycatch_pc);
+ DUK_ASSERT(instr != NULL);
+ DUK_ASSERT_DISABLE(flags >= DUK_BC_A_MIN);
+ DUK_ASSERT(flags <= DUK_BC_A_MAX);
+ instr->ins = DUK_ENC_OP_A_BC(DUK_OP_TRYCATCH, flags, reg_catch);
+}
+
+DUK_LOCAL void duk__emit_if_false_skip(duk_compiler_ctx *comp_ctx, duk_regconst_t regconst) {
+ duk__emit_a_b_c(comp_ctx,
+ DUK_OP_IF | DUK__EMIT_FLAG_NO_SHUFFLE_A | DUK__EMIT_FLAG_NO_SHUFFLE_C,
+ 0 /*false*/,
+ regconst,
+ 0 /*unused*/);
+}
+
+DUK_LOCAL void duk__emit_if_true_skip(duk_compiler_ctx *comp_ctx, duk_regconst_t regconst) {
+ duk__emit_a_b_c(comp_ctx,
+ DUK_OP_IF | DUK__EMIT_FLAG_NO_SHUFFLE_A | DUK__EMIT_FLAG_NO_SHUFFLE_C,
+ 1 /*true*/,
+ regconst,
+ 0 /*unused*/);
+}
+
+DUK_LOCAL void duk__emit_invalid(duk_compiler_ctx *comp_ctx) {
+ duk__emit_extraop_bc(comp_ctx, DUK_EXTRAOP_INVALID, 0);
+}
+
+/*
+ * Peephole optimizer for finished bytecode.
+ *
+ * Does not remove opcodes; currently only straightens out unconditional
+ * jump chains which are generated by several control structures.
+ */
+
+DUK_LOCAL void duk__peephole_optimize_bytecode(duk_compiler_ctx *comp_ctx) {
+ duk_compiler_instr *bc;
+ duk_small_uint_t iter;
+ duk_int_t i, n;
+ duk_int_t count_opt;
+
+ bc = (duk_compiler_instr *) (void *) DUK_BW_GET_BASEPTR(comp_ctx->thr, &comp_ctx->curr_func.bw_code);
+#if defined(DUK_USE_BUFLEN16)
+ /* No need to assert, buffer size maximum is 0xffff. */
+#else
+ DUK_ASSERT((duk_size_t) DUK_BW_GET_SIZE(comp_ctx->thr, &comp_ctx->curr_func.bw_code) / sizeof(duk_compiler_instr) <= (duk_size_t) DUK_INT_MAX); /* bytecode limits */
+#endif
+ n = (duk_int_t) (DUK_BW_GET_SIZE(comp_ctx->thr, &comp_ctx->curr_func.bw_code) / sizeof(duk_compiler_instr));
+
+ for (iter = 0; iter < DUK_COMPILER_PEEPHOLE_MAXITER; iter++) {
+ count_opt = 0;
+
+ for (i = 0; i < n; i++) {
+ duk_instr_t ins;
+ duk_int_t target_pc1;
+ duk_int_t target_pc2;
+
+ ins = bc[i].ins;
+ if (DUK_DEC_OP(ins) != DUK_OP_JUMP) {
+ continue;
+ }
+
+ target_pc1 = i + 1 + DUK_DEC_ABC(ins) - DUK_BC_JUMP_BIAS;
+ DUK_DDD(DUK_DDDPRINT("consider jump at pc %ld; target_pc=%ld", (long) i, (long) target_pc1));
+ DUK_ASSERT(target_pc1 >= 0);
+ DUK_ASSERT(target_pc1 < n);
+
+ /* Note: if target_pc1 == i, we'll optimize a jump to itself.
+ * This does not need to be checked for explicitly; the case
+ * is rare and max iter breaks us out.
+ */
+
+ ins = bc[target_pc1].ins;
+ if (DUK_DEC_OP(ins) != DUK_OP_JUMP) {
+ continue;
+ }
+
+ target_pc2 = target_pc1 + 1 + DUK_DEC_ABC(ins) - DUK_BC_JUMP_BIAS;
+
+ DUK_DDD(DUK_DDDPRINT("optimizing jump at pc %ld; old target is %ld -> new target is %ld",
+ (long) i, (long) target_pc1, (long) target_pc2));
+
+ bc[i].ins = DUK_ENC_OP_ABC(DUK_OP_JUMP, target_pc2 - (i + 1) + DUK_BC_JUMP_BIAS);
+
+ count_opt++;
+ }
+
+ DUK_DD(DUK_DDPRINT("optimized %ld jumps on peephole round %ld", (long) count_opt, (long) (iter + 1)));
+
+ if (count_opt == 0) {
+ break;
+ }
+ }
+}
+
+/*
+ * Intermediate value helpers
+ */
+
+#define DUK__ISREG(comp_ctx,x) (((x) & DUK__CONST_MARKER) == 0)
+#define DUK__ISCONST(comp_ctx,x) (((x) & DUK__CONST_MARKER) != 0)
+#define DUK__ISTEMP(comp_ctx,x) (DUK__ISREG((comp_ctx), (x)) && (duk_regconst_t) (x) >= (duk_regconst_t) ((comp_ctx)->curr_func.temp_first))
+#define DUK__GETTEMP(comp_ctx) ((comp_ctx)->curr_func.temp_next)
+#define DUK__SETTEMP(comp_ctx,x) ((comp_ctx)->curr_func.temp_next = (x)) /* dangerous: must only lower (temp_max not updated) */
+#define DUK__SETTEMP_CHECKMAX(comp_ctx,x) duk__settemp_checkmax((comp_ctx),(x))
+#define DUK__ALLOCTEMP(comp_ctx) duk__alloctemp((comp_ctx))
+#define DUK__ALLOCTEMPS(comp_ctx,count) duk__alloctemps((comp_ctx),(count))
+
+/* Flags for intermediate value coercions. A flag for using a forced reg
+ * is not needed, the forced_reg argument suffices and generates better
+ * code (it is checked as it is used).
+ */
+#define DUK__IVAL_FLAG_ALLOW_CONST (1 << 0) /* allow a constant to be returned */
+#define DUK__IVAL_FLAG_REQUIRE_TEMP (1 << 1) /* require a (mutable) temporary as a result (or a const if allowed) */
+#define DUK__IVAL_FLAG_REQUIRE_SHORT (1 << 2) /* require a short (8-bit) reg/const which fits into bytecode B/C slot */
+
+/* XXX: some code might benefit from DUK__SETTEMP_IFTEMP(ctx,x) */
+
+#if 0 /* enable manually for dumping */
+#define DUK__DUMP_ISPEC(compctx,ispec) do { duk__dump_ispec((compctx), (ispec)); } while (0)
+#define DUK__DUMP_IVALUE(compctx,ivalue) do { duk__dump_ivalue((compctx), (ivalue)); } while (0)
+
+DUK_LOCAL void duk__dump_ispec(duk_compiler_ctx *comp_ctx, duk_ispec *x) {
+ DUK_D(DUK_DPRINT("ispec dump: t=%ld regconst=0x%08lx, valstack_idx=%ld, value=%!T",
+ (long) x->t, (unsigned long) x->regconst, (long) x->valstack_idx,
+ duk_get_tval((duk_context *) comp_ctx->thr, x->valstack_idx)));
+}
+DUK_LOCAL void duk__dump_ivalue(duk_compiler_ctx *comp_ctx, duk_ivalue *x) {
+ DUK_D(DUK_DPRINT("ivalue dump: t=%ld op=%ld "
+ "x1={t=%ld regconst=0x%08lx valstack_idx=%ld value=%!T} "
+ "x2={t=%ld regconst=0x%08lx valstack_idx=%ld value=%!T}",
+ (long) x->t, (long) x->op,
+ (long) x->x1.t, (unsigned long) x->x1.regconst, (long) x->x1.valstack_idx,
+ duk_get_tval((duk_context *) comp_ctx->thr, x->x1.valstack_idx),
+ (long) x->x2.t, (unsigned long) x->x2.regconst, (long) x->x2.valstack_idx,
+ duk_get_tval((duk_context *) comp_ctx->thr, x->x2.valstack_idx)));
+}
+#else
+#define DUK__DUMP_ISPEC(comp_ctx,x) do {} while (0)
+#define DUK__DUMP_IVALUE(comp_ctx,x) do {} while (0)
+#endif
+
+DUK_LOCAL void duk__copy_ispec(duk_compiler_ctx *comp_ctx, duk_ispec *src, duk_ispec *dst) {
+ duk_context *ctx = (duk_context *) comp_ctx->thr;
+
+ dst->t = src->t;
+ dst->regconst = src->regconst;
+ duk_copy(ctx, src->valstack_idx, dst->valstack_idx);
+}
+
+DUK_LOCAL void duk__copy_ivalue(duk_compiler_ctx *comp_ctx, duk_ivalue *src, duk_ivalue *dst) {
+ duk_context *ctx = (duk_context *) comp_ctx->thr;
+
+ dst->t = src->t;
+ dst->op = src->op;
+ dst->x1.t = src->x1.t;
+ dst->x1.regconst = src->x1.regconst;
+ dst->x2.t = src->x2.t;
+ dst->x2.regconst = src->x2.regconst;
+ duk_copy(ctx, src->x1.valstack_idx, dst->x1.valstack_idx);
+ duk_copy(ctx, src->x2.valstack_idx, dst->x2.valstack_idx);
+}
+
+/* XXX: to util */
+DUK_LOCAL duk_bool_t duk__is_whole_get_int32(duk_double_t x, duk_int32_t *ival) {
+ duk_small_int_t c;
+ duk_int32_t t;
+
+ c = DUK_FPCLASSIFY(x);
+ if (c == DUK_FP_NORMAL || (c == DUK_FP_ZERO && !DUK_SIGNBIT(x))) {
+ /* Don't allow negative zero as it will cause trouble with
+ * LDINT+LDINTX. But positive zero is OK.
+ */
+ t = (duk_int32_t) x;
+ if ((duk_double_t) t == x) {
+ *ival = t;
+ return 1;
+ }
+ }
+
+ return 0;
+}
+
+DUK_LOCAL duk_reg_t duk__alloctemps(duk_compiler_ctx *comp_ctx, duk_small_int_t num) {
+ duk_reg_t res;
+
+ res = comp_ctx->curr_func.temp_next;
+ comp_ctx->curr_func.temp_next += num;
+
+ if (comp_ctx->curr_func.temp_next > DUK__MAX_TEMPS) { /* == DUK__MAX_TEMPS is OK */
+ DUK_ERROR_RANGE(comp_ctx->thr, DUK_STR_TEMP_LIMIT);
+ }
+
+ /* maintain highest 'used' temporary, needed to figure out nregs of function */
+ if (comp_ctx->curr_func.temp_next > comp_ctx->curr_func.temp_max) {
+ comp_ctx->curr_func.temp_max = comp_ctx->curr_func.temp_next;
+ }
+
+ return res;
+}
+
+DUK_LOCAL duk_reg_t duk__alloctemp(duk_compiler_ctx *comp_ctx) {
+ return duk__alloctemps(comp_ctx, 1);
+}
+
+DUK_LOCAL void duk__settemp_checkmax(duk_compiler_ctx *comp_ctx, duk_reg_t temp_next) {
+ comp_ctx->curr_func.temp_next = temp_next;
+ if (temp_next > comp_ctx->curr_func.temp_max) {
+ comp_ctx->curr_func.temp_max = temp_next;
+ }
+}
+
+/* get const for value at valstack top */
+DUK_LOCAL duk_regconst_t duk__getconst(duk_compiler_ctx *comp_ctx) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_compiler_func *f = &comp_ctx->curr_func;
+ duk_tval *tv1;
+ duk_int_t i, n, n_check;
+
+ n = (duk_int_t) duk_get_length(ctx, f->consts_idx);
+
+ tv1 = DUK_GET_TVAL_NEGIDX(ctx, -1);
+ DUK_ASSERT(tv1 != NULL);
+
+#if defined(DUK_USE_FASTINT)
+ /* Explicit check for fastint downgrade. */
+ DUK_TVAL_CHKFAST_INPLACE(tv1);
+#endif
+
+ /* Sanity workaround for handling functions with a large number of
+ * constants at least somewhat reasonably. Otherwise checking whether
+ * we already have the constant would grow very slow (as it is O(N^2)).
+ */
+ n_check = (n > DUK__GETCONST_MAX_CONSTS_CHECK ? DUK__GETCONST_MAX_CONSTS_CHECK : n);
+ for (i = 0; i < n_check; i++) {
+ duk_tval *tv2 = DUK_HOBJECT_A_GET_VALUE_PTR(thr->heap, f->h_consts, i);
+
+ /* Strict equality is NOT enough, because we cannot use the same
+ * constant for e.g. +0 and -0.
+ */
+ if (duk_js_samevalue(tv1, tv2)) {
+ DUK_DDD(DUK_DDDPRINT("reused existing constant for %!T -> const index %ld",
+ (duk_tval *) tv1, (long) i));
+ duk_pop(ctx);
+ return (duk_regconst_t) (i | DUK__CONST_MARKER);
+ }
+ }
+
+ if (n > DUK__MAX_CONSTS) {
+ DUK_ERROR_RANGE(comp_ctx->thr, DUK_STR_CONST_LIMIT);
+ }
+
+ DUK_DDD(DUK_DDDPRINT("allocating new constant for %!T -> const index %ld",
+ (duk_tval *) tv1, (long) n));
+ (void) duk_put_prop_index(ctx, f->consts_idx, n); /* invalidates tv1, tv2 */
+ return (duk_regconst_t) (n | DUK__CONST_MARKER);
+}
+
+/* Get the value represented by an duk_ispec to a register or constant.
+ * The caller can control the result by indicating whether or not:
+ *
+ * (1) a constant is allowed (sometimes the caller needs the result to
+ * be in a register)
+ *
+ * (2) a temporary register is required (usually when caller requires
+ * the register to be safely mutable; normally either a bound
+ * register or a temporary register are both OK)
+ *
+ * (3) a forced register target needs to be used
+ *
+ * Bytecode may be emitted to generate the necessary value. The return
+ * value is either a register or a constant.
+ */
+
+DUK_LOCAL
+duk_regconst_t duk__ispec_toregconst_raw(duk_compiler_ctx *comp_ctx,
+ duk_ispec *x,
+ duk_reg_t forced_reg,
+ duk_small_uint_t flags) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+
+ DUK_DDD(DUK_DDDPRINT("duk__ispec_toregconst_raw(): x={%ld:%ld:%!T}, "
+ "forced_reg=%ld, flags 0x%08lx: allow_const=%ld require_temp=%ld require_short=%ld",
+ (long) x->t,
+ (long) x->regconst,
+ (duk_tval *) duk_get_tval(ctx, x->valstack_idx),
+ (long) forced_reg,
+ (unsigned long) flags,
+ (long) ((flags & DUK__IVAL_FLAG_ALLOW_CONST) ? 1 : 0),
+ (long) ((flags & DUK__IVAL_FLAG_REQUIRE_TEMP) ? 1 : 0),
+ (long) ((flags & DUK__IVAL_FLAG_REQUIRE_SHORT) ? 1 : 0)));
+
+ switch (x->t) {
+ case DUK_ISPEC_VALUE: {
+ duk_tval *tv;
+
+ tv = DUK_GET_TVAL_POSIDX(ctx, x->valstack_idx);
+ DUK_ASSERT(tv != NULL);
+
+ switch (DUK_TVAL_GET_TAG(tv)) {
+ case DUK_TAG_UNDEFINED: {
+ /* Note: although there is no 'undefined' literal, undefined
+ * values can occur during compilation as a result of e.g.
+ * the 'void' operator.
+ */
+ duk_reg_t dest = (forced_reg >= 0 ? forced_reg : DUK__ALLOCTEMP(comp_ctx));
+ duk__emit_extraop_bc(comp_ctx, DUK_EXTRAOP_LDUNDEF, (duk_regconst_t) dest);
+ return (duk_regconst_t) dest;
+ }
+ case DUK_TAG_NULL: {
+ duk_reg_t dest = (forced_reg >= 0 ? forced_reg : DUK__ALLOCTEMP(comp_ctx));
+ duk__emit_extraop_bc(comp_ctx, DUK_EXTRAOP_LDNULL, (duk_regconst_t) dest);
+ return (duk_regconst_t) dest;
+ }
+ case DUK_TAG_BOOLEAN: {
+ duk_reg_t dest = (forced_reg >= 0 ? forced_reg : DUK__ALLOCTEMP(comp_ctx));
+ duk__emit_extraop_bc(comp_ctx,
+ (DUK_TVAL_GET_BOOLEAN(tv) ? DUK_EXTRAOP_LDTRUE : DUK_EXTRAOP_LDFALSE),
+ (duk_regconst_t) dest);
+ return (duk_regconst_t) dest;
+ }
+ case DUK_TAG_POINTER: {
+ DUK_UNREACHABLE();
+ break;
+ }
+ case DUK_TAG_STRING: {
+ duk_hstring *h;
+ duk_reg_t dest;
+ duk_regconst_t constidx;
+
+ h = DUK_TVAL_GET_STRING(tv);
+ DUK_UNREF(h);
+ DUK_ASSERT(h != NULL);
+
+#if 0 /* XXX: to be implemented? */
+ /* Use special opcodes to load short strings */
+ if (DUK_HSTRING_GET_BYTELEN(h) <= 2) {
+ /* Encode into a single opcode (18 bits can encode 1-2 bytes + length indicator) */
+ } else if (DUK_HSTRING_GET_BYTELEN(h) <= 6) {
+ /* Encode into a double constant (53 bits can encode 6*8 = 48 bits + 3-bit length */
+ }
+#endif
+ duk_dup(ctx, x->valstack_idx);
+ constidx = duk__getconst(comp_ctx);
+
+ if (flags & DUK__IVAL_FLAG_ALLOW_CONST) {
+ return constidx;
+ }
+
+ dest = (forced_reg >= 0 ? forced_reg : DUK__ALLOCTEMP(comp_ctx));
+ duk__emit_a_bc(comp_ctx, DUK_OP_LDCONST, (duk_regconst_t) dest, constidx);
+ return (duk_regconst_t) dest;
+ }
+ case DUK_TAG_OBJECT: {
+ DUK_UNREACHABLE();
+ break;
+ }
+ case DUK_TAG_BUFFER: {
+ DUK_UNREACHABLE();
+ break;
+ }
+ case DUK_TAG_LIGHTFUNC: {
+ DUK_UNREACHABLE();
+ break;
+ }
+#if defined(DUK_USE_FASTINT)
+ case DUK_TAG_FASTINT:
+#endif
+ default: {
+ /* number */
+ duk_reg_t dest;
+ duk_regconst_t constidx;
+ duk_double_t dval;
+ duk_int32_t ival;
+
+ DUK_ASSERT(!DUK_TVAL_IS_UNUSED(tv));
+ DUK_ASSERT(DUK_TVAL_IS_NUMBER(tv));
+ dval = DUK_TVAL_GET_NUMBER(tv);
+
+ if (!(flags & DUK__IVAL_FLAG_ALLOW_CONST)) {
+ /* A number can be loaded either through a constant, using
+ * LDINT, or using LDINT+LDINTX. LDINT is always a size win,
+ * LDINT+LDINTX is not if the constant is used multiple times.
+ * Currently always prefer LDINT+LDINTX over a double constant.
+ */
+
+ if (duk__is_whole_get_int32(dval, &ival)) {
+ dest = (forced_reg >= 0 ? forced_reg : DUK__ALLOCTEMP(comp_ctx));
+ duk__emit_load_int32(comp_ctx, dest, ival);
+ return (duk_regconst_t) dest;
+ }
+ }
+
+ duk_dup(ctx, x->valstack_idx);
+ constidx = duk__getconst(comp_ctx);
+
+ if (flags & DUK__IVAL_FLAG_ALLOW_CONST) {
+ return constidx;
+ } else {
+ dest = (forced_reg >= 0 ? forced_reg : DUK__ALLOCTEMP(comp_ctx));
+ duk__emit_a_bc(comp_ctx, DUK_OP_LDCONST, (duk_regconst_t) dest, constidx);
+ return (duk_regconst_t) dest;
+ }
+ }
+ } /* end switch */
+ }
+ case DUK_ISPEC_REGCONST: {
+ if (forced_reg >= 0) {
+ if (x->regconst & DUK__CONST_MARKER) {
+ duk__emit_a_bc(comp_ctx, DUK_OP_LDCONST, forced_reg, x->regconst);
+ } else if (x->regconst != (duk_regconst_t) forced_reg) {
+ duk__emit_a_bc(comp_ctx, DUK_OP_LDREG, forced_reg, x->regconst);
+ } else {
+ ; /* already in correct reg */
+ }
+ return (duk_regconst_t) forced_reg;
+ }
+
+ DUK_ASSERT(forced_reg < 0);
+ if (x->regconst & DUK__CONST_MARKER) {
+ if (!(flags & DUK__IVAL_FLAG_ALLOW_CONST)) {
+ duk_reg_t dest = DUK__ALLOCTEMP(comp_ctx);
+ duk__emit_a_bc(comp_ctx, DUK_OP_LDCONST, (duk_regconst_t) dest, x->regconst);
+ return (duk_regconst_t) dest;
+ }
+ return x->regconst;
+ }
+
+ DUK_ASSERT(forced_reg < 0 && !(x->regconst & DUK__CONST_MARKER));
+ if ((flags & DUK__IVAL_FLAG_REQUIRE_TEMP) && !DUK__ISTEMP(comp_ctx, x->regconst)) {
+ duk_reg_t dest = DUK__ALLOCTEMP(comp_ctx);
+ duk__emit_a_bc(comp_ctx, DUK_OP_LDREG, (duk_regconst_t) dest, x->regconst);
+ return (duk_regconst_t) dest;
+ }
+ return x->regconst;
+ }
+ default: {
+ break;
+ }
+ }
+
+ DUK_ERROR_INTERNAL_DEFMSG(thr);
+ return 0;
+}
+
+DUK_LOCAL void duk__ispec_toforcedreg(duk_compiler_ctx *comp_ctx, duk_ispec *x, duk_reg_t forced_reg) {
+ DUK_ASSERT(forced_reg >= 0);
+ (void) duk__ispec_toregconst_raw(comp_ctx, x, forced_reg, 0 /*flags*/);
+}
+
+/* Coerce an duk_ivalue to a 'plain' value by generating the necessary
+ * arithmetic operations, property access, or variable access bytecode.
+ * The duk_ivalue argument ('x') is converted into a plain value as a
+ * side effect.
+ */
+DUK_LOCAL void duk__ivalue_toplain_raw(duk_compiler_ctx *comp_ctx, duk_ivalue *x, duk_reg_t forced_reg) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+
+ DUK_DDD(DUK_DDDPRINT("duk__ivalue_toplain_raw(): x={t=%ld,op=%ld,x1={%ld:%ld:%!T},x2={%ld:%ld:%!T}}, "
+ "forced_reg=%ld",
+ (long) x->t, (long) x->op,
+ (long) x->x1.t, (long) x->x1.regconst,
+ (duk_tval *) duk_get_tval(ctx, x->x1.valstack_idx),
+ (long) x->x2.t, (long) x->x2.regconst,
+ (duk_tval *) duk_get_tval(ctx, x->x2.valstack_idx),
+ (long) forced_reg));
+
+ switch (x->t) {
+ case DUK_IVAL_PLAIN: {
+ return;
+ }
+ /* XXX: support unary arithmetic ivalues (useful?) */
+ case DUK_IVAL_ARITH:
+ case DUK_IVAL_ARITH_EXTRAOP: {
+ duk_regconst_t arg1;
+ duk_regconst_t arg2;
+ duk_reg_t dest;
+ duk_tval *tv1;
+ duk_tval *tv2;
+
+ DUK_DDD(DUK_DDDPRINT("arith to plain conversion"));
+
+ /* inline arithmetic check for constant values */
+ /* XXX: use the exactly same arithmetic function here as in executor */
+ if (x->x1.t == DUK_ISPEC_VALUE && x->x2.t == DUK_ISPEC_VALUE && x->t == DUK_IVAL_ARITH) {
+ tv1 = DUK_GET_TVAL_POSIDX(ctx, x->x1.valstack_idx);
+ tv2 = DUK_GET_TVAL_POSIDX(ctx, x->x2.valstack_idx);
+ DUK_ASSERT(tv1 != NULL);
+ DUK_ASSERT(tv2 != NULL);
+
+ DUK_DDD(DUK_DDDPRINT("arith: tv1=%!T, tv2=%!T",
+ (duk_tval *) tv1,
+ (duk_tval *) tv2));
+
+ if (DUK_TVAL_IS_NUMBER(tv1) && DUK_TVAL_IS_NUMBER(tv2)) {
+ duk_double_t d1 = DUK_TVAL_GET_NUMBER(tv1);
+ duk_double_t d2 = DUK_TVAL_GET_NUMBER(tv2);
+ duk_double_t d3;
+ duk_bool_t accept = 1;
+
+ DUK_DDD(DUK_DDDPRINT("arith inline check: d1=%lf, d2=%lf, op=%ld",
+ (double) d1, (double) d2, (long) x->op));
+ switch (x->op) {
+ case DUK_OP_ADD: d3 = d1 + d2; break;
+ case DUK_OP_SUB: d3 = d1 - d2; break;
+ case DUK_OP_MUL: d3 = d1 * d2; break;
+ case DUK_OP_DIV: d3 = d1 / d2; break;
+ default: accept = 0; break;
+ }
+
+ if (accept) {
+ duk_double_union du;
+ du.d = d3;
+ DUK_DBLUNION_NORMALIZE_NAN_CHECK(&du);
+ d3 = du.d;
+
+ x->t = DUK_IVAL_PLAIN;
+ DUK_ASSERT(x->x1.t == DUK_ISPEC_VALUE);
+ DUK_TVAL_SET_NUMBER(tv1, d3); /* old value is number: no refcount */
+ return;
+ }
+ } else if (x->op == DUK_OP_ADD && DUK_TVAL_IS_STRING(tv1) && DUK_TVAL_IS_STRING(tv2)) {
+ /* inline string concatenation */
+ duk_dup(ctx, x->x1.valstack_idx);
+ duk_dup(ctx, x->x2.valstack_idx);
+ duk_concat(ctx, 2);
+ duk_replace(ctx, x->x1.valstack_idx);
+ x->t = DUK_IVAL_PLAIN;
+ DUK_ASSERT(x->x1.t == DUK_ISPEC_VALUE);
+ return;
+ }
+ }
+
+ arg1 = duk__ispec_toregconst_raw(comp_ctx, &x->x1, -1, DUK__IVAL_FLAG_ALLOW_CONST | DUK__IVAL_FLAG_REQUIRE_SHORT /*flags*/);
+ arg2 = duk__ispec_toregconst_raw(comp_ctx, &x->x2, -1, DUK__IVAL_FLAG_ALLOW_CONST | DUK__IVAL_FLAG_REQUIRE_SHORT /*flags*/);
+
+ /* If forced reg, use it as destination. Otherwise try to
+ * use either coerced ispec if it is a temporary.
+ *
+ * When using extraops, avoid reusing arg2 as dest because that
+ * would lead to an LDREG shuffle below. We still can't guarantee
+ * dest != arg2 because we may have a forced_reg.
+ */
+ if (forced_reg >= 0) {
+ dest = forced_reg;
+ } else if (DUK__ISTEMP(comp_ctx, arg1)) {
+ dest = (duk_reg_t) arg1;
+ } else if (DUK__ISTEMP(comp_ctx, arg2) && x->t != DUK_IVAL_ARITH_EXTRAOP) {
+ dest = (duk_reg_t) arg2;
+ } else {
+ dest = DUK__ALLOCTEMP(comp_ctx);
+ }
+
+ /* Extraop arithmetic opcodes must have destination same as
+ * first source. If second source matches destination we need
+ * a temporary register to avoid clobbering the second source.
+ *
+ * XXX: change calling code to avoid this situation in most cases.
+ */
+
+ if (x->t == DUK_IVAL_ARITH_EXTRAOP) {
+ if (!(DUK__ISREG(comp_ctx, arg1) && (duk_reg_t) arg1 == dest)) {
+ if (DUK__ISREG(comp_ctx, arg2) && (duk_reg_t) arg2 == dest) {
+ /* arg2 would be clobbered so reassign it to a temp. */
+ duk_reg_t tempreg;
+ tempreg = DUK__ALLOCTEMP(comp_ctx);
+ duk__emit_a_bc(comp_ctx, DUK_OP_LDREG, tempreg, arg2);
+ arg2 = tempreg;
+ }
+
+ if (DUK__ISREG(comp_ctx, arg1)) {
+ duk__emit_a_bc(comp_ctx, DUK_OP_LDREG, dest, arg1);
+ } else {
+ DUK_ASSERT(DUK__ISCONST(comp_ctx, arg1));
+ duk__emit_a_bc(comp_ctx, DUK_OP_LDCONST, dest, arg1);
+ }
+ }
+
+ /* Note: special DUK__EMIT_FLAG_B_IS_TARGETSOURCE
+ * used to indicate that B is both a source and a
+ * target register. When shuffled, it needs to be
+ * both input and output shuffled.
+ */
+ DUK_ASSERT(DUK__ISREG(comp_ctx, dest));
+ duk__emit_extraop_b_c(comp_ctx,
+ x->op | DUK__EMIT_FLAG_B_IS_TARGET |
+ DUK__EMIT_FLAG_B_IS_TARGETSOURCE,
+ (duk_regconst_t) dest,
+ (duk_regconst_t) arg2);
+
+ } else {
+ DUK_ASSERT(DUK__ISREG(comp_ctx, dest));
+ duk__emit_a_b_c(comp_ctx, x->op, (duk_regconst_t) dest, arg1, arg2);
+ }
+
+ x->t = DUK_IVAL_PLAIN;
+ x->x1.t = DUK_ISPEC_REGCONST;
+ x->x1.regconst = (duk_regconst_t) dest;
+ return;
+ }
+ case DUK_IVAL_PROP: {
+ /* XXX: very similar to DUK_IVAL_ARITH - merge? */
+ duk_regconst_t arg1;
+ duk_regconst_t arg2;
+ duk_reg_t dest;
+
+ /* Need a short reg/const, does not have to be a mutable temp. */
+ arg1 = duk__ispec_toregconst_raw(comp_ctx, &x->x1, -1, DUK__IVAL_FLAG_ALLOW_CONST | DUK__IVAL_FLAG_REQUIRE_SHORT /*flags*/);
+ arg2 = duk__ispec_toregconst_raw(comp_ctx, &x->x2, -1, DUK__IVAL_FLAG_ALLOW_CONST | DUK__IVAL_FLAG_REQUIRE_SHORT /*flags*/);
+
+ /* Pick a destination register. If either base value or key
+ * happens to be a temp value, reuse it as the destination.
+ *
+ * XXX: The temp must be a "mutable" one, i.e. such that no
+ * other expression is using it anymore. Here this should be
+ * the case because the value of a property access expression
+ * is neither the base nor the key, but the lookup result.
+ */
+
+ if (forced_reg >= 0) {
+ dest = forced_reg;
+ } else if (DUK__ISTEMP(comp_ctx, arg1)) {
+ dest = (duk_reg_t) arg1;
+ } else if (DUK__ISTEMP(comp_ctx, arg2)) {
+ dest = (duk_reg_t) arg2;
+ } else {
+ dest = DUK__ALLOCTEMP(comp_ctx);
+ }
+
+ duk__emit_a_b_c(comp_ctx, DUK_OP_GETPROP, (duk_regconst_t) dest, arg1, arg2);
+
+ x->t = DUK_IVAL_PLAIN;
+ x->x1.t = DUK_ISPEC_REGCONST;
+ x->x1.regconst = (duk_regconst_t) dest;
+ return;
+ }
+ case DUK_IVAL_VAR: {
+ /* x1 must be a string */
+ duk_reg_t dest;
+ duk_reg_t reg_varbind;
+ duk_regconst_t rc_varname;
+
+ DUK_ASSERT(x->x1.t == DUK_ISPEC_VALUE);
+
+ duk_dup(ctx, x->x1.valstack_idx);
+ if (duk__lookup_lhs(comp_ctx, ®_varbind, &rc_varname)) {
+ x->t = DUK_IVAL_PLAIN;
+ x->x1.t = DUK_ISPEC_REGCONST;
+ x->x1.regconst = (duk_regconst_t) reg_varbind;
+ } else {
+ dest = (forced_reg >= 0 ? forced_reg : DUK__ALLOCTEMP(comp_ctx));
+ duk__emit_a_bc(comp_ctx, DUK_OP_GETVAR, (duk_regconst_t) dest, rc_varname);
+ x->t = DUK_IVAL_PLAIN;
+ x->x1.t = DUK_ISPEC_REGCONST;
+ x->x1.regconst = (duk_regconst_t) dest;
+ }
+ return;
+ }
+ case DUK_IVAL_NONE:
+ default: {
+ DUK_D(DUK_DPRINT("invalid ivalue type: %ld", (long) x->t));
+ break;
+ }
+ }
+
+ DUK_ERROR_INTERNAL_DEFMSG(thr);
+ return;
+}
+
+/* evaluate to plain value, no forced register (temp/bound reg both ok) */
+DUK_LOCAL void duk__ivalue_toplain(duk_compiler_ctx *comp_ctx, duk_ivalue *x) {
+ duk__ivalue_toplain_raw(comp_ctx, x, -1 /*forced_reg*/);
+}
+
+/* evaluate to final form (e.g. coerce GETPROP to code), throw away temp */
+DUK_LOCAL void duk__ivalue_toplain_ignore(duk_compiler_ctx *comp_ctx, duk_ivalue *x) {
+ duk_reg_t temp;
+
+ /* If duk__ivalue_toplain_raw() allocates a temp, forget it and
+ * restore next temp state.
+ */
+ temp = DUK__GETTEMP(comp_ctx);
+ duk__ivalue_toplain_raw(comp_ctx, x, -1 /*forced_reg*/);
+ DUK__SETTEMP(comp_ctx, temp);
+}
+
+/* Coerce an duk_ivalue to a register or constant; result register may
+ * be a temp or a bound register.
+ *
+ * The duk_ivalue argument ('x') is converted into a regconst as a
+ * side effect.
+ */
+DUK_LOCAL
+duk_regconst_t duk__ivalue_toregconst_raw(duk_compiler_ctx *comp_ctx,
+ duk_ivalue *x,
+ duk_reg_t forced_reg,
+ duk_small_uint_t flags) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_regconst_t reg;
+ DUK_UNREF(thr);
+ DUK_UNREF(ctx);
+
+ DUK_DDD(DUK_DDDPRINT("duk__ivalue_toregconst_raw(): x={t=%ld,op=%ld,x1={%ld:%ld:%!T},x2={%ld:%ld:%!T}}, "
+ "forced_reg=%ld, flags 0x%08lx: allow_const=%ld require_temp=%ld require_short=%ld",
+ (long) x->t, (long) x->op,
+ (long) x->x1.t, (long) x->x1.regconst,
+ (duk_tval *) duk_get_tval(ctx, x->x1.valstack_idx),
+ (long) x->x2.t, (long) x->x2.regconst,
+ (duk_tval *) duk_get_tval(ctx, x->x2.valstack_idx),
+ (long) forced_reg,
+ (unsigned long) flags,
+ (long) ((flags & DUK__IVAL_FLAG_ALLOW_CONST) ? 1 : 0),
+ (long) ((flags & DUK__IVAL_FLAG_REQUIRE_TEMP) ? 1 : 0),
+ (long) ((flags & DUK__IVAL_FLAG_REQUIRE_SHORT) ? 1 : 0)));
+
+ /* first coerce to a plain value */
+ duk__ivalue_toplain_raw(comp_ctx, x, forced_reg);
+ DUK_ASSERT(x->t == DUK_IVAL_PLAIN);
+
+ /* then to a register */
+ reg = duk__ispec_toregconst_raw(comp_ctx, &x->x1, forced_reg, flags);
+ x->x1.t = DUK_ISPEC_REGCONST;
+ x->x1.regconst = reg;
+
+ return reg;
+}
+
+DUK_LOCAL duk_reg_t duk__ivalue_toreg(duk_compiler_ctx *comp_ctx, duk_ivalue *x) {
+ return duk__ivalue_toregconst_raw(comp_ctx, x, -1, 0 /*flags*/);
+}
+
+#if 0 /* unused */
+DUK_LOCAL duk_reg_t duk__ivalue_totemp(duk_compiler_ctx *comp_ctx, duk_ivalue *x) {
+ return duk__ivalue_toregconst_raw(comp_ctx, x, -1, DUK__IVAL_FLAG_REQUIRE_TEMP /*flags*/);
+}
+#endif
+
+DUK_LOCAL void duk__ivalue_toforcedreg(duk_compiler_ctx *comp_ctx, duk_ivalue *x, duk_int_t forced_reg) {
+ DUK_ASSERT(forced_reg >= 0);
+ (void) duk__ivalue_toregconst_raw(comp_ctx, x, forced_reg, 0 /*flags*/);
+}
+
+DUK_LOCAL duk_regconst_t duk__ivalue_toregconst(duk_compiler_ctx *comp_ctx, duk_ivalue *x) {
+ return duk__ivalue_toregconst_raw(comp_ctx, x, -1, DUK__IVAL_FLAG_ALLOW_CONST /*flags*/);
+}
+
+DUK_LOCAL duk_regconst_t duk__ivalue_totempconst(duk_compiler_ctx *comp_ctx, duk_ivalue *x) {
+ return duk__ivalue_toregconst_raw(comp_ctx, x, -1, DUK__IVAL_FLAG_ALLOW_CONST | DUK__IVAL_FLAG_REQUIRE_TEMP /*flags*/);
+}
+
+/* The issues below can be solved with better flags */
+
+/* XXX: many operations actually want toforcedtemp() -- brand new temp? */
+/* XXX: need a toplain_ignore() which will only coerce a value to a temp
+ * register if it might have a side effect. Side-effect free values do not
+ * need to be coerced.
+ */
+
+/*
+ * Identifier handling
+ */
+
+DUK_LOCAL duk_reg_t duk__lookup_active_register_binding(duk_compiler_ctx *comp_ctx) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_hstring *h_varname;
+ duk_reg_t ret;
+
+ DUK_DDD(DUK_DDDPRINT("resolving identifier reference to '%!T'",
+ (duk_tval *) duk_get_tval(ctx, -1)));
+
+ /*
+ * Special name handling
+ */
+
+ h_varname = duk_get_hstring(ctx, -1);
+ DUK_ASSERT(h_varname != NULL);
+
+ if (h_varname == DUK_HTHREAD_STRING_LC_ARGUMENTS(thr)) {
+ DUK_DDD(DUK_DDDPRINT("flagging function as accessing 'arguments'"));
+ comp_ctx->curr_func.id_access_arguments = 1;
+ }
+
+ /*
+ * Inside one or more 'with' statements fall back to slow path always.
+ * (See e.g. test-stmt-with.js.)
+ */
+
+ if (comp_ctx->curr_func.with_depth > 0) {
+ DUK_DDD(DUK_DDDPRINT("identifier lookup inside a 'with' -> fall back to slow path"));
+ goto slow_path;
+ }
+
+ /*
+ * Any catch bindings ("catch (e)") also affect identifier binding.
+ *
+ * Currently, the varmap is modified for the duration of the catch
+ * clause to ensure any identifier accesses with the catch variable
+ * name will use slow path.
+ */
+
+ duk_get_prop(ctx, comp_ctx->curr_func.varmap_idx);
+ if (duk_is_number(ctx, -1)) {
+ ret = duk_to_int(ctx, -1);
+ duk_pop(ctx);
+ } else {
+ duk_pop(ctx);
+ goto slow_path;
+ }
+
+ DUK_DDD(DUK_DDDPRINT("identifier lookup -> reg %ld", (long) ret));
+ return ret;
+
+ slow_path:
+ DUK_DDD(DUK_DDDPRINT("identifier lookup -> slow path"));
+
+ comp_ctx->curr_func.id_access_slow = 1;
+ return (duk_reg_t) -1;
+}
+
+/* Lookup an identifier name in the current varmap, indicating whether the
+ * identifier is register-bound and if not, allocating a constant for the
+ * identifier name. Returns 1 if register-bound, 0 otherwise. Caller can
+ * also check (out_reg_varbind >= 0) to check whether or not identifier is
+ * register bound. The caller must NOT use out_rc_varname at all unless
+ * return code is 0 or out_reg_varbind is < 0; this is becuase out_rc_varname
+ * is unsigned and doesn't have a "unused" / none value.
+ */
+DUK_LOCAL duk_bool_t duk__lookup_lhs(duk_compiler_ctx *comp_ctx, duk_reg_t *out_reg_varbind, duk_regconst_t *out_rc_varname) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_reg_t reg_varbind;
+ duk_regconst_t rc_varname;
+
+ /* [ ... varname ] */
+
+ duk_dup_top(ctx);
+ reg_varbind = duk__lookup_active_register_binding(comp_ctx);
+
+ if (reg_varbind >= 0) {
+ *out_reg_varbind = reg_varbind;
+ *out_rc_varname = 0; /* duk_regconst_t is unsigned, so use 0 as dummy value (ignored by caller) */
+ duk_pop(ctx);
+ return 1;
+ } else {
+ rc_varname = duk__getconst(comp_ctx);
+ *out_reg_varbind = -1;
+ *out_rc_varname = rc_varname;
+ return 0;
+ }
+}
+
+/*
+ * Label handling
+ *
+ * Labels are initially added with flags prohibiting both break and continue.
+ * When the statement type is finally uncovered (after potentially multiple
+ * labels), all the labels are updated to allow/prohibit break and continue.
+ */
+
+DUK_LOCAL void duk__add_label(duk_compiler_ctx *comp_ctx, duk_hstring *h_label, duk_int_t pc_label, duk_int_t label_id) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_size_t n;
+ duk_size_t new_size;
+ duk_uint8_t *p;
+ duk_labelinfo *li_start, *li;
+
+ /* Duplicate (shadowing) labels are not allowed, except for the empty
+ * labels (which are used as default labels for switch and iteration
+ * statements).
+ *
+ * We could also allow shadowing of non-empty pending labels without any
+ * other issues than breaking the required label shadowing requirements
+ * of the E5 specification, see Section 12.12.
+ */
+
+ p = (duk_uint8_t *) DUK_HBUFFER_DYNAMIC_GET_DATA_PTR(thr->heap, comp_ctx->curr_func.h_labelinfos);
+ li_start = (duk_labelinfo *) (void *) p;
+ li = (duk_labelinfo *) (void *) (p + DUK_HBUFFER_GET_SIZE(comp_ctx->curr_func.h_labelinfos));
+ n = (duk_size_t) (li - li_start);
+
+ while (li > li_start) {
+ li--;
+
+ if (li->h_label == h_label && h_label != DUK_HTHREAD_STRING_EMPTY_STRING(thr)) {
+ DUK_ERROR_SYNTAX(thr, DUK_STR_DUPLICATE_LABEL);
+ }
+ }
+
+ duk_push_hstring(ctx, h_label);
+ DUK_ASSERT(n <= DUK_UARRIDX_MAX); /* label limits */
+ (void) duk_put_prop_index(ctx, comp_ctx->curr_func.labelnames_idx, (duk_uarridx_t) n);
+
+ new_size = (n + 1) * sizeof(duk_labelinfo);
+ duk_hbuffer_resize(thr, comp_ctx->curr_func.h_labelinfos, new_size);
+ /* XXX: spare handling, slow now */
+
+ /* relookup after possible realloc */
+ p = (duk_uint8_t *) DUK_HBUFFER_DYNAMIC_GET_DATA_PTR(thr->heap, comp_ctx->curr_func.h_labelinfos);
+ li_start = (duk_labelinfo *) (void *) p;
+ DUK_UNREF(li_start); /* silence scan-build warning */
+ li = (duk_labelinfo *) (void *) (p + DUK_HBUFFER_GET_SIZE(comp_ctx->curr_func.h_labelinfos));
+ li--;
+
+ /* Labels can be used for iteration statements but also for other statements,
+ * in particular a label can be used for a block statement. All cases of a
+ * named label accept a 'break' so that flag is set here. Iteration statements
+ * also allow 'continue', so that flag is updated when we figure out the
+ * statement type.
+ */
+
+ li->flags = DUK_LABEL_FLAG_ALLOW_BREAK;
+ li->label_id = label_id;
+ li->h_label = h_label;
+ li->catch_depth = comp_ctx->curr_func.catch_depth; /* catch depth from current func */
+ li->pc_label = pc_label;
+
+ DUK_DDD(DUK_DDDPRINT("registered label: flags=0x%08lx, id=%ld, name=%!O, catch_depth=%ld, pc_label=%ld",
+ (unsigned long) li->flags, (long) li->label_id, (duk_heaphdr *) li->h_label,
+ (long) li->catch_depth, (long) li->pc_label));
+}
+
+/* Update all labels with matching label_id. */
+DUK_LOCAL void duk__update_label_flags(duk_compiler_ctx *comp_ctx, duk_int_t label_id, duk_small_uint_t flags) {
+ duk_uint8_t *p;
+ duk_labelinfo *li_start, *li;
+
+ p = (duk_uint8_t *) DUK_HBUFFER_DYNAMIC_GET_DATA_PTR(comp_ctx->thr->heap, comp_ctx->curr_func.h_labelinfos);
+ li_start = (duk_labelinfo *) (void *) p;
+ li = (duk_labelinfo *) (void *) (p + DUK_HBUFFER_GET_SIZE(comp_ctx->curr_func.h_labelinfos));
+
+ /* Match labels starting from latest; once label_id no longer matches, we can
+ * safely exit without checking the rest of the labels (only the topmost labels
+ * are ever updated).
+ */
+ while (li > li_start) {
+ li--;
+
+ if (li->label_id != label_id) {
+ break;
+ }
+
+ DUK_DDD(DUK_DDDPRINT("updating (overwriting) label flags for li=%p, label_id=%ld, flags=%ld",
+ (void *) li, (long) label_id, (long) flags));
+
+ li->flags = flags;
+ }
+}
+
+/* Lookup active label information. Break/continue distinction is necessary to handle switch
+ * statement related labels correctly: a switch will only catch a 'break', not a 'continue'.
+ *
+ * An explicit label cannot appear multiple times in the active set, but empty labels (unlabelled
+ * iteration and switch statements) can. A break will match the closest unlabelled or labelled
+ * statement. A continue will match the closest unlabelled or labelled iteration statement. It is
+ * a syntax error if a continue matches a labelled switch statement; because an explicit label cannot
+ * be duplicated, the continue cannot match any valid label outside the switch.
+ *
+ * A side effect of these rules is that a LABEL statement related to a switch should never actually
+ * catch a continue abrupt completion at run-time. Hence an INVALID opcode can be placed in the
+ * continue slot of the switch's LABEL statement.
+ */
+
+/* XXX: awkward, especially the bunch of separate output values -> output struct? */
+DUK_LOCAL void duk__lookup_active_label(duk_compiler_ctx *comp_ctx, duk_hstring *h_label, duk_bool_t is_break, duk_int_t *out_label_id, duk_int_t *out_label_catch_depth, duk_int_t *out_label_pc, duk_bool_t *out_is_closest) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_uint8_t *p;
+ duk_labelinfo *li_start, *li_end, *li;
+ duk_bool_t match = 0;
+
+ DUK_DDD(DUK_DDDPRINT("looking up active label: label='%!O', is_break=%ld",
+ (duk_heaphdr *) h_label, (long) is_break));
+
+ DUK_UNREF(ctx);
+
+ p = (duk_uint8_t *) DUK_HBUFFER_DYNAMIC_GET_DATA_PTR(thr->heap, comp_ctx->curr_func.h_labelinfos);
+ li_start = (duk_labelinfo *) (void *) p;
+ li_end = (duk_labelinfo *) (void *) (p + DUK_HBUFFER_GET_SIZE(comp_ctx->curr_func.h_labelinfos));
+ li = li_end;
+
+ /* Match labels starting from latest label because there can be duplicate empty
+ * labels in the label set.
+ */
+ while (li > li_start) {
+ li--;
+
+ if (li->h_label != h_label) {
+ DUK_DDD(DUK_DDDPRINT("labelinfo[%ld] ->'%!O' != %!O",
+ (long) (li - li_start),
+ (duk_heaphdr *) li->h_label,
+ (duk_heaphdr *) h_label));
+ continue;
+ }
+
+ DUK_DDD(DUK_DDDPRINT("labelinfo[%ld] -> '%!O' label name matches (still need to check type)",
+ (long) (li - li_start), (duk_heaphdr *) h_label));
+
+ /* currently all labels accept a break, so no explicit check for it now */
+ DUK_ASSERT(li->flags & DUK_LABEL_FLAG_ALLOW_BREAK);
+
+ if (is_break) {
+ /* break matches always */
+ match = 1;
+ break;
+ } else if (li->flags & DUK_LABEL_FLAG_ALLOW_CONTINUE) {
+ /* iteration statements allow continue */
+ match = 1;
+ break;
+ } else {
+ /* continue matched this label -- we can only continue if this is the empty
+ * label, for which duplication is allowed, and thus there is hope of
+ * finding a match deeper in the label stack.
+ */
+ if (h_label != DUK_HTHREAD_STRING_EMPTY_STRING(thr)) {
+ DUK_ERROR_SYNTAX(thr, DUK_STR_INVALID_LABEL);
+ } else {
+ DUK_DDD(DUK_DDDPRINT("continue matched an empty label which does not "
+ "allow a continue -> continue lookup deeper in label stack"));
+ }
+ }
+ }
+ /* XXX: match flag is awkward, rework */
+ if (!match) {
+ DUK_ERROR_SYNTAX(thr, DUK_STR_INVALID_LABEL);
+ }
+
+ DUK_DDD(DUK_DDDPRINT("label match: %!O -> label_id %ld, catch_depth=%ld, pc_label=%ld",
+ (duk_heaphdr *) h_label, (long) li->label_id,
+ (long) li->catch_depth, (long) li->pc_label));
+
+ *out_label_id = li->label_id;
+ *out_label_catch_depth = li->catch_depth;
+ *out_label_pc = li->pc_label;
+ *out_is_closest = (li == li_end - 1);
+}
+
+DUK_LOCAL void duk__reset_labels_to_length(duk_compiler_ctx *comp_ctx, duk_int_t len) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_size_t new_size;
+
+ /* XXX: duk_set_length */
+ new_size = sizeof(duk_labelinfo) * (duk_size_t) len;
+ duk_push_int(ctx, len);
+ duk_put_prop_stridx(ctx, comp_ctx->curr_func.labelnames_idx, DUK_STRIDX_LENGTH);
+ duk_hbuffer_resize(thr, comp_ctx->curr_func.h_labelinfos, new_size);
+}
+
+/*
+ * Expression parsing: duk__expr_nud(), duk__expr_led(), duk__expr_lbp(), and helpers.
+ *
+ * - duk__expr_nud(): ("null denotation"): process prev_token as a "start" of an expression (e.g. literal)
+ * - duk__expr_led(): ("left denotation"): process prev_token in the "middle" of an expression (e.g. operator)
+ * - duk__expr_lbp(): ("left-binding power"): return left-binding power of curr_token
+ */
+
+/* object literal key tracking flags */
+#define DUK__OBJ_LIT_KEY_PLAIN (1 << 0) /* key encountered as a plain property */
+#define DUK__OBJ_LIT_KEY_GET (1 << 1) /* key encountered as a getter */
+#define DUK__OBJ_LIT_KEY_SET (1 << 2) /* key encountered as a setter */
+
+DUK_LOCAL void duk__nud_array_literal(duk_compiler_ctx *comp_ctx, duk_ivalue *res) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_reg_t reg_obj; /* result reg */
+ duk_reg_t reg_temp; /* temp reg */
+ duk_reg_t temp_start; /* temp reg value for start of loop */
+ duk_small_uint_t max_init_values; /* max # of values initialized in one MPUTARR set */
+ duk_small_uint_t num_values; /* number of values in current MPUTARR set */
+ duk_uarridx_t curr_idx; /* current (next) array index */
+ duk_uarridx_t start_idx; /* start array index of current MPUTARR set */
+ duk_uarridx_t init_idx; /* last array index explicitly initialized, +1 */
+ duk_bool_t require_comma; /* next loop requires a comma */
+
+ /* DUK_TOK_LBRACKET already eaten, current token is right after that */
+ DUK_ASSERT(comp_ctx->prev_token.t == DUK_TOK_LBRACKET);
+
+ max_init_values = DUK__MAX_ARRAY_INIT_VALUES; /* XXX: depend on available temps? */
+
+ reg_obj = DUK__ALLOCTEMP(comp_ctx);
+ duk__emit_extraop_b_c(comp_ctx,
+ DUK_EXTRAOP_NEWARR | DUK__EMIT_FLAG_B_IS_TARGET,
+ reg_obj,
+ 0); /* XXX: patch initial size afterwards? */
+ temp_start = DUK__GETTEMP(comp_ctx);
+
+ /*
+ * Emit initializers in sets of maximum max_init_values.
+ * Corner cases such as single value initializers do not have
+ * special handling now.
+ *
+ * Elided elements must not be emitted as 'undefined' values,
+ * because such values would be enumerable (which is incorrect).
+ * Also note that trailing elisions must be reflected in the
+ * length of the final array but cause no elements to be actually
+ * inserted.
+ */
+
+ curr_idx = 0;
+ init_idx = 0; /* tracks maximum initialized index + 1 */
+ start_idx = 0;
+ require_comma = 0;
+
+ for (;;) {
+ num_values = 0;
+ DUK__SETTEMP(comp_ctx, temp_start);
+
+ if (comp_ctx->curr_token.t == DUK_TOK_RBRACKET) {
+ break;
+ }
+
+ for (;;) {
+ if (comp_ctx->curr_token.t == DUK_TOK_RBRACKET) {
+ /* the outer loop will recheck and exit */
+ break;
+ }
+
+ /* comma check */
+ if (require_comma) {
+ if (comp_ctx->curr_token.t == DUK_TOK_COMMA) {
+ /* comma after a value, expected */
+ duk__advance(comp_ctx);
+ require_comma = 0;
+ continue;
+ } else {
+ goto syntax_error;
+ }
+ } else {
+ if (comp_ctx->curr_token.t == DUK_TOK_COMMA) {
+ /* elision - flush */
+ curr_idx++;
+ duk__advance(comp_ctx);
+ /* if num_values > 0, MPUTARR emitted by outer loop after break */
+ break;
+ }
+ }
+ /* else an array initializer element */
+
+ /* initial index */
+ if (num_values == 0) {
+ start_idx = curr_idx;
+ reg_temp = DUK__ALLOCTEMP(comp_ctx);
+ duk__emit_load_int32(comp_ctx, reg_temp, (duk_int32_t) start_idx);
+ }
+
+ reg_temp = DUK__ALLOCTEMP(comp_ctx); /* alloc temp just in case, to update max temp */
+ DUK__SETTEMP(comp_ctx, reg_temp);
+ duk__expr_toforcedreg(comp_ctx, res, DUK__BP_COMMA /*rbp_flags*/, reg_temp /*forced_reg*/);
+ DUK__SETTEMP(comp_ctx, reg_temp + 1);
+
+ num_values++;
+ curr_idx++;
+ require_comma = 1;
+
+ if (num_values >= max_init_values) {
+ /* MPUTARR emitted by outer loop */
+ break;
+ }
+ }
+
+ if (num_values > 0) {
+ /* - A is a source register (it's not a write target, but used
+ * to identify the target object) but can be shuffled.
+ * - B cannot be shuffled normally because it identifies a range
+ * of registers, the emitter has special handling for this
+ * (the "no shuffle" flag must not be set).
+ * - C is a non-register number and cannot be shuffled, but
+ * never needs to be.
+ */
+ duk__emit_a_b_c(comp_ctx,
+ DUK_OP_MPUTARR |
+ DUK__EMIT_FLAG_NO_SHUFFLE_C |
+ DUK__EMIT_FLAG_A_IS_SOURCE,
+ (duk_regconst_t) reg_obj,
+ (duk_regconst_t) temp_start,
+ (duk_regconst_t) num_values);
+ init_idx = start_idx + num_values;
+
+ /* num_values and temp_start reset at top of outer loop */
+ }
+ }
+
+ DUK_ASSERT(comp_ctx->curr_token.t == DUK_TOK_RBRACKET);
+ duk__advance(comp_ctx);
+
+ DUK_DDD(DUK_DDDPRINT("array literal done, curridx=%ld, initidx=%ld",
+ (long) curr_idx, (long) init_idx));
+
+ /* trailing elisions? */
+ if (curr_idx > init_idx) {
+ /* yes, must set array length explicitly */
+ DUK_DDD(DUK_DDDPRINT("array literal has trailing elisions which affect its length"));
+ reg_temp = DUK__ALLOCTEMP(comp_ctx);
+ duk__emit_load_int32(comp_ctx, reg_temp, (duk_int_t) curr_idx);
+ duk__emit_extraop_b_c(comp_ctx,
+ DUK_EXTRAOP_SETALEN,
+ (duk_regconst_t) reg_obj,
+ (duk_regconst_t) reg_temp);
+ }
+
+ DUK__SETTEMP(comp_ctx, temp_start);
+
+ res->t = DUK_IVAL_PLAIN;
+ res->x1.t = DUK_ISPEC_REGCONST;
+ res->x1.regconst = (duk_regconst_t) reg_obj;
+ return;
+
+ syntax_error:
+ DUK_ERROR_SYNTAX(thr, DUK_STR_INVALID_ARRAY_LITERAL);
+}
+
+/* duplicate/invalid key checks; returns 1 if syntax error */
+DUK_LOCAL duk_bool_t duk__nud_object_literal_key_check(duk_compiler_ctx *comp_ctx, duk_small_uint_t new_key_flags) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_small_uint_t key_flags;
+
+ /* [ ... key_obj key ] */
+
+ DUK_ASSERT(duk_is_string(ctx, -1));
+
+ /*
+ * 'key_obj' tracks keys encountered so far by associating an
+ * integer with flags with already encountered keys. The checks
+ * below implement E5 Section 11.1.5, step 4 for production:
+ *
+ * PropertyNameAndValueList: PropertyNameAndValueList , PropertyAssignment
+ */
+
+ duk_dup(ctx, -1); /* [ ... key_obj key key ] */
+ duk_get_prop(ctx, -3); /* [ ... key_obj key val ] */
+ key_flags = duk_to_int(ctx, -1);
+ duk_pop(ctx); /* [ ... key_obj key ] */
+
+ if (new_key_flags & DUK__OBJ_LIT_KEY_PLAIN) {
+ if ((key_flags & DUK__OBJ_LIT_KEY_PLAIN) && comp_ctx->curr_func.is_strict) {
+ /* step 4.a */
+ DUK_DDD(DUK_DDDPRINT("duplicate key: plain key appears twice in strict mode"));
+ return 1;
+ }
+ if (key_flags & (DUK__OBJ_LIT_KEY_GET | DUK__OBJ_LIT_KEY_SET)) {
+ /* step 4.c */
+ DUK_DDD(DUK_DDDPRINT("duplicate key: plain key encountered after setter/getter"));
+ return 1;
+ }
+ } else {
+ if (key_flags & DUK__OBJ_LIT_KEY_PLAIN) {
+ /* step 4.b */
+ DUK_DDD(DUK_DDDPRINT("duplicate key: getter/setter encountered after plain key"));
+ return 1;
+ }
+ if (key_flags & new_key_flags) {
+ /* step 4.d */
+ DUK_DDD(DUK_DDDPRINT("duplicate key: getter/setter encountered twice"));
+ return 1;
+ }
+ }
+
+ new_key_flags |= key_flags;
+ DUK_DDD(DUK_DDDPRINT("setting/updating key %!T flags: 0x%08lx -> 0x%08lx",
+ (duk_tval *) duk_get_tval(ctx, -1),
+ (unsigned long) key_flags,
+ (unsigned long) new_key_flags));
+ duk_dup(ctx, -1);
+ duk_push_int(ctx, new_key_flags); /* [ ... key_obj key key flags ] */
+ duk_put_prop(ctx, -4); /* [ ... key_obj key ] */
+
+ return 0;
+}
+
+DUK_LOCAL void duk__nud_object_literal(duk_compiler_ctx *comp_ctx, duk_ivalue *res) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_reg_t reg_obj; /* result reg */
+ duk_reg_t reg_key; /* temp reg for key literal */
+ duk_reg_t reg_temp; /* temp reg */
+ duk_reg_t temp_start; /* temp reg value for start of loop */
+ duk_small_uint_t max_init_pairs; /* max # of key-value pairs initialized in one MPUTOBJ set */
+ duk_small_uint_t num_pairs; /* number of pairs in current MPUTOBJ set */
+ duk_bool_t first; /* first value: comma must not precede the value */
+ duk_bool_t is_set, is_get; /* temps */
+
+ DUK_ASSERT(comp_ctx->prev_token.t == DUK_TOK_LCURLY);
+
+ max_init_pairs = DUK__MAX_OBJECT_INIT_PAIRS; /* XXX: depend on available temps? */
+
+ reg_obj = DUK__ALLOCTEMP(comp_ctx);
+ duk__emit_extraop_b_c(comp_ctx,
+ DUK_EXTRAOP_NEWOBJ | DUK__EMIT_FLAG_B_IS_TARGET,
+ reg_obj,
+ 0); /* XXX: patch initial size afterwards? */
+ temp_start = DUK__GETTEMP(comp_ctx);
+
+ /* temp object for tracking / detecting duplicate keys */
+ duk_push_object(ctx);
+
+ /*
+ * Emit initializers in sets of maximum max_init_pairs keys.
+ * Setter/getter is handled separately and terminates the
+ * current set of initializer values. Corner cases such as
+ * single value initializers do not have special handling now.
+ */
+
+ first = 1;
+ for (;;) {
+ num_pairs = 0;
+ DUK__SETTEMP(comp_ctx, temp_start);
+
+ if (comp_ctx->curr_token.t == DUK_TOK_RCURLY) {
+ break;
+ }
+
+ for (;;) {
+ /*
+ * Three possible element formats:
+ * 1) PropertyName : AssignmentExpression
+ * 2) get PropertyName () { FunctionBody }
+ * 3) set PropertyName ( PropertySetParameterList ) { FunctionBody }
+ *
+ * PropertyName can be IdentifierName (includes reserved words), a string
+ * literal, or a number literal. Note that IdentifierName allows 'get' and
+ * 'set' too, so we need to look ahead to the next token to distinguish:
+ *
+ * { get : 1 }
+ *
+ * and
+ *
+ * { get foo() { return 1 } }
+ * { get get() { return 1 } } // 'get' as getter propertyname
+ *
+ * Finally, a trailing comma is allowed.
+ *
+ * Key name is coerced to string at compile time (and ends up as a
+ * a string constant) even for numeric keys (e.g. "{1:'foo'}").
+ * These could be emitted using e.g. LDINT, but that seems hardly
+ * worth the effort and would increase code size.
+ */
+
+ DUK_DDD(DUK_DDDPRINT("object literal inner loop, curr_token->t = %ld",
+ (long) comp_ctx->curr_token.t));
+
+ if (comp_ctx->curr_token.t == DUK_TOK_RCURLY) {
+ /* the outer loop will recheck and exit */
+ break;
+ }
+ if (num_pairs >= max_init_pairs) {
+ /* MPUTOBJ emitted by outer loop */
+ break;
+ }
+
+ if (first) {
+ first = 0;
+ } else {
+ if (comp_ctx->curr_token.t != DUK_TOK_COMMA) {
+ goto syntax_error;
+ }
+ duk__advance(comp_ctx);
+ if (comp_ctx->curr_token.t == DUK_TOK_RCURLY) {
+ /* trailing comma followed by rcurly */
+ break;
+ }
+ }
+
+ /* advance to get one step of lookup */
+ duk__advance(comp_ctx);
+
+ /* NOTE: "get" and "set" are not officially ReservedWords and the lexer
+ * currently treats them always like ordinary identifiers (DUK_TOK_GET
+ * and DUK_TOK_SET are unused). They need to be detected based on the
+ * identifier string content.
+ */
+
+ is_get = (comp_ctx->prev_token.t == DUK_TOK_IDENTIFIER &&
+ comp_ctx->prev_token.str1 == DUK_HTHREAD_STRING_GET(thr));
+ is_set = (comp_ctx->prev_token.t == DUK_TOK_IDENTIFIER &&
+ comp_ctx->prev_token.str1 == DUK_HTHREAD_STRING_SET(thr));
+ if ((is_get || is_set) && comp_ctx->curr_token.t != DUK_TOK_COLON) {
+ /* getter/setter */
+ duk_int_t fnum;
+
+ if (comp_ctx->curr_token.t_nores == DUK_TOK_IDENTIFIER ||
+ comp_ctx->curr_token.t_nores == DUK_TOK_STRING) {
+ /* same handling for identifiers and strings */
+ DUK_ASSERT(comp_ctx->curr_token.str1 != NULL);
+ duk_push_hstring(ctx, comp_ctx->curr_token.str1);
+ } else if (comp_ctx->curr_token.t == DUK_TOK_NUMBER) {
+ duk_push_number(ctx, comp_ctx->curr_token.num);
+ duk_to_string(ctx, -1);
+ } else {
+ goto syntax_error;
+ }
+
+ DUK_ASSERT(duk_is_string(ctx, -1));
+ if (duk__nud_object_literal_key_check(comp_ctx,
+ (is_get ? DUK__OBJ_LIT_KEY_GET : DUK__OBJ_LIT_KEY_SET))) {
+ goto syntax_error;
+ }
+ reg_key = duk__getconst(comp_ctx);
+
+ if (num_pairs > 0) {
+ /* - A is a source register (it's not a write target, but used
+ * to identify the target object) but can be shuffled.
+ * - B cannot be shuffled normally because it identifies a range
+ * of registers, the emitter has special handling for this
+ * (the "no shuffle" flag must not be set).
+ * - C is a non-register number and cannot be shuffled, but
+ * never needs to be.
+ */
+ duk__emit_a_b_c(comp_ctx,
+ DUK_OP_MPUTOBJ |
+ DUK__EMIT_FLAG_NO_SHUFFLE_C |
+ DUK__EMIT_FLAG_A_IS_SOURCE,
+ reg_obj,
+ temp_start,
+ num_pairs);
+ num_pairs = 0;
+ DUK__SETTEMP(comp_ctx, temp_start);
+ }
+
+ /* curr_token = get/set name */
+ fnum = duk__parse_func_like_fnum(comp_ctx, 0 /*is_decl*/, 1 /*is_setget*/);
+
+ DUK_ASSERT(DUK__GETTEMP(comp_ctx) == temp_start);
+ reg_temp = DUK__ALLOCTEMP(comp_ctx);
+ duk__emit_a_bc(comp_ctx,
+ DUK_OP_LDCONST,
+ (duk_regconst_t) reg_temp,
+ (duk_regconst_t) reg_key);
+ reg_temp = DUK__ALLOCTEMP(comp_ctx);
+ duk__emit_a_bc(comp_ctx,
+ DUK_OP_CLOSURE,
+ (duk_regconst_t) reg_temp,
+ (duk_regconst_t) fnum);
+
+ /* Slot C is used in a non-standard fashion (range of regs),
+ * emitter code has special handling for it (must not set the
+ * "no shuffle" flag).
+ */
+ duk__emit_extraop_b_c(comp_ctx,
+ (is_get ? DUK_EXTRAOP_INITGET : DUK_EXTRAOP_INITSET),
+ reg_obj,
+ temp_start); /* temp_start+0 = key, temp_start+1 = closure */
+
+ DUK__SETTEMP(comp_ctx, temp_start);
+ } else {
+ /* normal key/value */
+ if (comp_ctx->prev_token.t_nores == DUK_TOK_IDENTIFIER ||
+ comp_ctx->prev_token.t_nores == DUK_TOK_STRING) {
+ /* same handling for identifiers and strings */
+ DUK_ASSERT(comp_ctx->prev_token.str1 != NULL);
+ duk_push_hstring(ctx, comp_ctx->prev_token.str1);
+ } else if (comp_ctx->prev_token.t == DUK_TOK_NUMBER) {
+ duk_push_number(ctx, comp_ctx->prev_token.num);
+ duk_to_string(ctx, -1);
+ } else {
+ goto syntax_error;
+ }
+
+ DUK_ASSERT(duk_is_string(ctx, -1));
+ if (duk__nud_object_literal_key_check(comp_ctx, DUK__OBJ_LIT_KEY_PLAIN)) {
+ goto syntax_error;
+ }
+ reg_key = duk__getconst(comp_ctx);
+
+ reg_temp = DUK__ALLOCTEMP(comp_ctx);
+ duk__emit_a_bc(comp_ctx,
+ DUK_OP_LDCONST,
+ (duk_regconst_t) reg_temp,
+ (duk_regconst_t) reg_key);
+ duk__advance_expect(comp_ctx, DUK_TOK_COLON);
+
+ reg_temp = DUK__ALLOCTEMP(comp_ctx); /* alloc temp just in case, to update max temp */
+ DUK__SETTEMP(comp_ctx, reg_temp);
+ duk__expr_toforcedreg(comp_ctx, res, DUK__BP_COMMA /*rbp_flags*/, reg_temp /*forced_reg*/);
+ DUK__SETTEMP(comp_ctx, reg_temp + 1);
+
+ num_pairs++;
+ }
+ }
+
+ if (num_pairs > 0) {
+ /* See MPUTOBJ comments above. */
+ duk__emit_a_b_c(comp_ctx,
+ DUK_OP_MPUTOBJ |
+ DUK__EMIT_FLAG_NO_SHUFFLE_C |
+ DUK__EMIT_FLAG_A_IS_SOURCE,
+ reg_obj,
+ temp_start,
+ num_pairs);
+
+ /* num_pairs and temp_start reset at top of outer loop */
+ }
+ }
+
+ DUK_ASSERT(comp_ctx->curr_token.t == DUK_TOK_RCURLY);
+ duk__advance(comp_ctx);
+
+ DUK__SETTEMP(comp_ctx, temp_start);
+
+ res->t = DUK_IVAL_PLAIN;
+ res->x1.t = DUK_ISPEC_REGCONST;
+ res->x1.regconst = (duk_regconst_t) reg_obj;
+
+ DUK_DDD(DUK_DDDPRINT("final tracking object: %!T",
+ (duk_tval *) duk_get_tval(ctx, -1)));
+ duk_pop(ctx);
+ return;
+
+ syntax_error:
+ DUK_ERROR_SYNTAX(thr, DUK_STR_INVALID_OBJECT_LITERAL);
+}
+
+/* Parse argument list. Arguments are written to temps starting from
+ * "next temp". Returns number of arguments parsed. Expects left paren
+ * to be already eaten, and eats the right paren before returning.
+ */
+DUK_LOCAL duk_int_t duk__parse_arguments(duk_compiler_ctx *comp_ctx, duk_ivalue *res) {
+ duk_int_t nargs = 0;
+ duk_reg_t reg_temp;
+
+ /* Note: expect that caller has already eaten the left paren */
+
+ DUK_DDD(DUK_DDDPRINT("start parsing arguments, prev_token.t=%ld, curr_token.t=%ld",
+ (long) comp_ctx->prev_token.t, (long) comp_ctx->curr_token.t));
+
+ for (;;) {
+ if (comp_ctx->curr_token.t == DUK_TOK_RPAREN) {
+ break;
+ }
+ if (nargs > 0) {
+ duk__advance_expect(comp_ctx, DUK_TOK_COMMA);
+ }
+
+ /* We want the argument expression value to go to "next temp"
+ * without additional moves. That should almost always be the
+ * case, but we double check after expression parsing.
+ *
+ * This is not the cleanest possible approach.
+ */
+
+ reg_temp = DUK__ALLOCTEMP(comp_ctx); /* bump up "allocated" reg count, just in case */
+ DUK__SETTEMP(comp_ctx, reg_temp);
+
+ /* binding power must be high enough to NOT allow comma expressions directly */
+ duk__expr_toforcedreg(comp_ctx, res, DUK__BP_COMMA /*rbp_flags*/, reg_temp); /* always allow 'in', coerce to 'tr' just in case */
+
+ DUK__SETTEMP(comp_ctx, reg_temp + 1);
+ nargs++;
+
+ DUK_DDD(DUK_DDDPRINT("argument #%ld written into reg %ld", (long) nargs, (long) reg_temp));
+ }
+
+ /* eat the right paren */
+ duk__advance_expect(comp_ctx, DUK_TOK_RPAREN);
+
+ DUK_DDD(DUK_DDDPRINT("end parsing arguments"));
+
+ return nargs;
+}
+
+DUK_LOCAL duk_bool_t duk__expr_is_empty(duk_compiler_ctx *comp_ctx) {
+ /* empty expressions can be detected conveniently with nud/led counts */
+ return (comp_ctx->curr_func.nud_count == 0) &&
+ (comp_ctx->curr_func.led_count == 0);
+}
+
+DUK_LOCAL void duk__expr_nud(duk_compiler_ctx *comp_ctx, duk_ivalue *res) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_token *tk;
+ duk_reg_t temp_at_entry;
+ duk_small_int_t tok;
+ duk_uint32_t args; /* temp variable to pass constants and flags to shared code */
+
+ /*
+ * ctx->prev_token token to process with duk__expr_nud()
+ * ctx->curr_token updated by caller
+ *
+ * Note: the token in the switch below has already been eaten.
+ */
+
+ temp_at_entry = DUK__GETTEMP(comp_ctx);
+
+ comp_ctx->curr_func.nud_count++;
+
+ tk = &comp_ctx->prev_token;
+ tok = tk->t;
+ res->t = DUK_IVAL_NONE;
+
+ DUK_DDD(DUK_DDDPRINT("duk__expr_nud(), prev_token.t=%ld, allow_in=%ld, paren_level=%ld",
+ (long) tk->t, (long) comp_ctx->curr_func.allow_in, (long) comp_ctx->curr_func.paren_level));
+
+ switch (tok) {
+
+ /* PRIMARY EXPRESSIONS */
+
+ case DUK_TOK_THIS: {
+ duk_reg_t reg_temp;
+ reg_temp = DUK__ALLOCTEMP(comp_ctx);
+ duk__emit_extraop_bc(comp_ctx,
+ DUK_EXTRAOP_LDTHIS,
+ (duk_regconst_t) reg_temp);
+ res->t = DUK_IVAL_PLAIN;
+ res->x1.t = DUK_ISPEC_REGCONST;
+ res->x1.regconst = (duk_regconst_t) reg_temp;
+ return;
+ }
+ case DUK_TOK_IDENTIFIER: {
+ res->t = DUK_IVAL_VAR;
+ res->x1.t = DUK_ISPEC_VALUE;
+ duk_push_hstring(ctx, tk->str1);
+ duk_replace(ctx, res->x1.valstack_idx);
+ return;
+ }
+ case DUK_TOK_NULL: {
+ duk_push_null(ctx);
+ goto plain_value;
+ }
+ case DUK_TOK_TRUE: {
+ duk_push_true(ctx);
+ goto plain_value;
+ }
+ case DUK_TOK_FALSE: {
+ duk_push_false(ctx);
+ goto plain_value;
+ }
+ case DUK_TOK_NUMBER: {
+ duk_push_number(ctx, tk->num);
+ goto plain_value;
+ }
+ case DUK_TOK_STRING: {
+ DUK_ASSERT(tk->str1 != NULL);
+ duk_push_hstring(ctx, tk->str1);
+ goto plain_value;
+ }
+ case DUK_TOK_REGEXP: {
+#ifdef DUK_USE_REGEXP_SUPPORT
+ duk_reg_t reg_temp;
+ duk_regconst_t rc_re_bytecode; /* const */
+ duk_regconst_t rc_re_source; /* const */
+
+ DUK_ASSERT(tk->str1 != NULL);
+ DUK_ASSERT(tk->str2 != NULL);
+
+ DUK_DDD(DUK_DDDPRINT("emitting regexp op, str1=%!O, str2=%!O",
+ (duk_heaphdr *) tk->str1,
+ (duk_heaphdr *) tk->str2));
+
+ reg_temp = DUK__ALLOCTEMP(comp_ctx);
+ duk_push_hstring(ctx, tk->str1);
+ duk_push_hstring(ctx, tk->str2);
+
+ /* [ ... pattern flags ] */
+
+ duk_regexp_compile(thr);
+
+ /* [ ... escaped_source bytecode ] */
+
+ rc_re_bytecode = duk__getconst(comp_ctx);
+ rc_re_source = duk__getconst(comp_ctx);
+
+ duk__emit_a_b_c(comp_ctx,
+ DUK_OP_REGEXP,
+ (duk_regconst_t) reg_temp /*a*/,
+ rc_re_bytecode /*b*/,
+ rc_re_source /*c*/);
+
+ res->t = DUK_IVAL_PLAIN;
+ res->x1.t = DUK_ISPEC_REGCONST;
+ res->x1.regconst = (duk_regconst_t) reg_temp;
+ return;
+#else /* DUK_USE_REGEXP_SUPPORT */
+ goto syntax_error;
+#endif /* DUK_USE_REGEXP_SUPPORT */
+ }
+ case DUK_TOK_LBRACKET: {
+ DUK_DDD(DUK_DDDPRINT("parsing array literal"));
+ duk__nud_array_literal(comp_ctx, res);
+ return;
+ }
+ case DUK_TOK_LCURLY: {
+ DUK_DDD(DUK_DDDPRINT("parsing object literal"));
+ duk__nud_object_literal(comp_ctx, res);
+ return;
+ }
+ case DUK_TOK_LPAREN: {
+ duk_bool_t prev_allow_in;
+
+ comp_ctx->curr_func.paren_level++;
+ prev_allow_in = comp_ctx->curr_func.allow_in;
+ comp_ctx->curr_func.allow_in = 1; /* reset 'allow_in' for parenthesized expression */
+
+ duk__expr(comp_ctx, res, DUK__BP_FOR_EXPR /*rbp_flags*/); /* Expression, terminates at a ')' */
+
+ duk__advance_expect(comp_ctx, DUK_TOK_RPAREN);
+ comp_ctx->curr_func.allow_in = prev_allow_in;
+ comp_ctx->curr_func.paren_level--;
+ return;
+ }
+
+ /* MEMBER/NEW/CALL EXPRESSIONS */
+
+ case DUK_TOK_NEW: {
+ /*
+ * Parsing an expression starting with 'new' is tricky because
+ * there are multiple possible productions deriving from
+ * LeftHandSideExpression which begin with 'new'.
+ *
+ * We currently resort to one-token lookahead to distinguish the
+ * cases. Hopefully this is correct. The binding power must be
+ * such that parsing ends at an LPAREN (CallExpression) but not at
+ * a PERIOD or LBRACKET (MemberExpression).
+ *
+ * See doc/compiler.rst for discussion on the parsing approach,
+ * and testcases/test-dev-new.js for a bunch of documented tests.
+ */
+
+ duk_reg_t reg_target;
+ duk_int_t nargs;
+
+ DUK_DDD(DUK_DDDPRINT("begin parsing new expression"));
+
+ reg_target = DUK__ALLOCTEMP(comp_ctx);
+ duk__expr_toforcedreg(comp_ctx, res, DUK__BP_CALL /*rbp_flags*/, reg_target /*forced_reg*/);
+ DUK__SETTEMP(comp_ctx, reg_target + 1);
+
+ if (comp_ctx->curr_token.t == DUK_TOK_LPAREN) {
+ /* 'new' MemberExpression Arguments */
+ DUK_DDD(DUK_DDDPRINT("new expression has argument list"));
+ duk__advance(comp_ctx);
+ nargs = duk__parse_arguments(comp_ctx, res); /* parse args starting from "next temp", reg_target + 1 */
+ /* right paren eaten */
+ } else {
+ /* 'new' MemberExpression */
+ DUK_DDD(DUK_DDDPRINT("new expression has no argument list"));
+ nargs = 0;
+ }
+
+ /* Opcode slot C is used in a non-standard way, so shuffling
+ * is not allowed.
+ */
+ duk__emit_a_b_c(comp_ctx,
+ DUK_OP_NEW | DUK__EMIT_FLAG_NO_SHUFFLE_A | DUK__EMIT_FLAG_NO_SHUFFLE_C,
+ 0 /*unused*/,
+ reg_target /*target*/,
+ nargs /*num_args*/);
+
+ DUK_DDD(DUK_DDDPRINT("end parsing new expression"));
+
+ res->t = DUK_IVAL_PLAIN;
+ res->x1.t = DUK_ISPEC_REGCONST;
+ res->x1.regconst = (duk_regconst_t) reg_target;
+ return;
+ }
+
+ /* FUNCTION EXPRESSIONS */
+
+ case DUK_TOK_FUNCTION: {
+ /* Function expression. Note that any statement beginning with 'function'
+ * is handled by the statement parser as a function declaration, or a
+ * non-standard function expression/statement (or a SyntaxError). We only
+ * handle actual function expressions (occurring inside an expression) here.
+ *
+ * O(depth^2) parse count for inner functions is handled by recording a
+ * lexer offset on the first compilation pass, so that the function can
+ * be efficiently skipped on the second pass. This is encapsulated into
+ * duk__parse_func_like_fnum().
+ */
+
+ duk_reg_t reg_temp;
+ duk_int_t fnum;
+
+ reg_temp = DUK__ALLOCTEMP(comp_ctx);
+
+ /* curr_token follows 'function' */
+ fnum = duk__parse_func_like_fnum(comp_ctx, 0 /*is_decl*/, 0 /*is_setget*/);
+ DUK_DDD(DUK_DDDPRINT("parsed inner function -> fnum %ld", (long) fnum));
+
+ duk__emit_a_bc(comp_ctx,
+ DUK_OP_CLOSURE,
+ (duk_regconst_t) reg_temp /*a*/,
+ (duk_regconst_t) fnum /*bc*/);
+
+ res->t = DUK_IVAL_PLAIN;
+ res->x1.t = DUK_ISPEC_REGCONST;
+ res->x1.regconst = (duk_regconst_t) reg_temp;
+ return;
+ }
+
+ /* UNARY EXPRESSIONS */
+
+ case DUK_TOK_DELETE: {
+ /* Delete semantics are a bit tricky. The description in E5 specification
+ * is kind of confusing, because it distinguishes between resolvability of
+ * a reference (which is only known at runtime) seemingly at compile time
+ * (= SyntaxError throwing).
+ */
+ duk__expr(comp_ctx, res, DUK__BP_MULTIPLICATIVE /*rbp_flags*/); /* UnaryExpression */
+ if (res->t == DUK_IVAL_VAR) {
+ /* not allowed in strict mode, regardless of whether resolves;
+ * in non-strict mode DELVAR handles both non-resolving and
+ * resolving cases (the specification description is a bit confusing).
+ */
+
+ duk_reg_t reg_temp;
+ duk_reg_t reg_varbind;
+ duk_regconst_t rc_varname;
+
+ if (comp_ctx->curr_func.is_strict) {
+ DUK_ERROR_SYNTAX(thr, DUK_STR_CANNOT_DELETE_IDENTIFIER);
+ }
+
+ DUK__SETTEMP(comp_ctx, temp_at_entry);
+ reg_temp = DUK__ALLOCTEMP(comp_ctx);
+
+ duk_dup(ctx, res->x1.valstack_idx);
+ if (duk__lookup_lhs(comp_ctx, ®_varbind, &rc_varname)) {
+ /* register bound variables are non-configurable -> always false */
+ duk__emit_extraop_bc(comp_ctx,
+ DUK_EXTRAOP_LDFALSE,
+ (duk_regconst_t) reg_temp);
+ } else {
+ duk_dup(ctx, res->x1.valstack_idx);
+ rc_varname = duk__getconst(comp_ctx);
+ duk__emit_a_b(comp_ctx,
+ DUK_OP_DELVAR,
+ (duk_regconst_t) reg_temp,
+ (duk_regconst_t) rc_varname);
+ }
+ res->t = DUK_IVAL_PLAIN;
+ res->x1.t = DUK_ISPEC_REGCONST;
+ res->x1.regconst = (duk_regconst_t) reg_temp;
+ } else if (res->t == DUK_IVAL_PROP) {
+ duk_reg_t reg_temp;
+ duk_reg_t reg_obj;
+ duk_regconst_t rc_key;
+
+ DUK__SETTEMP(comp_ctx, temp_at_entry);
+ reg_temp = DUK__ALLOCTEMP(comp_ctx);
+ reg_obj = duk__ispec_toregconst_raw(comp_ctx, &res->x1, -1 /*forced_reg*/, 0 /*flags*/); /* don't allow const */
+ rc_key = duk__ispec_toregconst_raw(comp_ctx, &res->x2, -1 /*forced_reg*/, DUK__IVAL_FLAG_ALLOW_CONST /*flags*/);
+ duk__emit_a_b_c(comp_ctx,
+ DUK_OP_DELPROP,
+ (duk_regconst_t) reg_temp,
+ (duk_regconst_t) reg_obj,
+ rc_key);
+
+ res->t = DUK_IVAL_PLAIN;
+ res->x1.t = DUK_ISPEC_REGCONST;
+ res->x1.regconst = (duk_regconst_t) reg_temp;
+ } else {
+ /* non-Reference deletion is always 'true', even in strict mode */
+ duk_push_true(ctx);
+ goto plain_value;
+ }
+ return;
+ }
+ case DUK_TOK_VOID: {
+ duk__expr_toplain_ignore(comp_ctx, res, DUK__BP_MULTIPLICATIVE /*rbp_flags*/); /* UnaryExpression */
+ duk_push_undefined(ctx);
+ goto plain_value;
+ }
+ case DUK_TOK_TYPEOF: {
+ /* 'typeof' must handle unresolvable references without throwing
+ * a ReferenceError (E5 Section 11.4.3). Register mapped values
+ * will never be unresolvable so special handling is only required
+ * when an identifier is a "slow path" one.
+ */
+ duk__expr(comp_ctx, res, DUK__BP_MULTIPLICATIVE /*rbp_flags*/); /* UnaryExpression */
+
+ if (res->t == DUK_IVAL_VAR) {
+ duk_reg_t reg_varbind;
+ duk_regconst_t rc_varname;
+ duk_reg_t reg_temp;
+
+ duk_dup(ctx, res->x1.valstack_idx);
+ if (!duk__lookup_lhs(comp_ctx, ®_varbind, &rc_varname)) {
+ DUK_DDD(DUK_DDDPRINT("typeof for an identifier name which could not be resolved "
+ "at compile time, need to use special run-time handling"));
+ reg_temp = DUK__ALLOCTEMP(comp_ctx);
+ duk__emit_extraop_b_c(comp_ctx,
+ DUK_EXTRAOP_TYPEOFID | DUK__EMIT_FLAG_B_IS_TARGET,
+ reg_temp,
+ rc_varname);
+ res->t = DUK_IVAL_PLAIN;
+ res->x1.t = DUK_ISPEC_REGCONST;
+ res->x1.regconst = (duk_regconst_t) reg_temp;
+ return;
+ }
+ }
+
+ args = (DUK_EXTRAOP_TYPEOF << 8) + 0;
+ goto unary_extraop;
+ }
+ case DUK_TOK_INCREMENT: {
+ args = (DUK_OP_PREINCR << 8) + 0;
+ goto preincdec;
+ }
+ case DUK_TOK_DECREMENT: {
+ args = (DUK_OP_PREDECR << 8) + 0;
+ goto preincdec;
+ }
+ case DUK_TOK_ADD: {
+ /* unary plus */
+ duk__expr(comp_ctx, res, DUK__BP_MULTIPLICATIVE /*rbp_flags*/); /* UnaryExpression */
+ if (res->t == DUK_IVAL_PLAIN && res->x1.t == DUK_ISPEC_VALUE &&
+ duk_is_number(ctx, res->x1.valstack_idx)) {
+ /* unary plus of a number is identity */
+ ;
+ return;
+ }
+ args = (DUK_EXTRAOP_UNP << 8) + 0;
+ goto unary_extraop;
+ }
+ case DUK_TOK_SUB: {
+ /* unary minus */
+ duk__expr(comp_ctx, res, DUK__BP_MULTIPLICATIVE /*rbp_flags*/); /* UnaryExpression */
+ if (res->t == DUK_IVAL_PLAIN && res->x1.t == DUK_ISPEC_VALUE &&
+ duk_is_number(ctx, res->x1.valstack_idx)) {
+ /* this optimization is important to handle negative literals
+ * (which are not directly provided by the lexical grammar)
+ */
+ duk_tval *tv_num;
+ duk_double_union du;
+
+ tv_num = DUK_GET_TVAL_POSIDX(ctx, res->x1.valstack_idx);
+ DUK_ASSERT(tv_num != NULL);
+ DUK_ASSERT(DUK_TVAL_IS_NUMBER(tv_num));
+ du.d = DUK_TVAL_GET_NUMBER(tv_num);
+ du.d = -du.d;
+ DUK_DBLUNION_NORMALIZE_NAN_CHECK(&du);
+ DUK_TVAL_SET_NUMBER(tv_num, du.d);
+ return;
+ }
+ args = (DUK_EXTRAOP_UNM << 8) + 0;
+ goto unary_extraop;
+ }
+ case DUK_TOK_BNOT: {
+ duk__expr(comp_ctx, res, DUK__BP_MULTIPLICATIVE /*rbp_flags*/); /* UnaryExpression */
+ args = (DUK_EXTRAOP_BNOT << 8) + 0;
+ goto unary_extraop;
+ }
+ case DUK_TOK_LNOT: {
+ duk__expr(comp_ctx, res, DUK__BP_MULTIPLICATIVE /*rbp_flags*/); /* UnaryExpression */
+ if (res->t == DUK_IVAL_PLAIN && res->x1.t == DUK_ISPEC_VALUE) {
+ /* Very minimal inlining to handle common idioms '!0' and '!1',
+ * and also boolean arguments like '!false' and '!true'.
+ */
+ duk_tval *tv_val;
+
+ tv_val = DUK_GET_TVAL_POSIDX(ctx, res->x1.valstack_idx);
+ DUK_ASSERT(tv_val != NULL);
+ if (DUK_TVAL_IS_NUMBER(tv_val)) {
+ duk_double_t d;
+ d = DUK_TVAL_GET_NUMBER(tv_val);
+ if (d == 0.0) {
+ /* Matches both +0 and -0 on purpose. */
+ DUK_DDD(DUK_DDDPRINT("inlined lnot: !0 -> true"));
+ DUK_TVAL_SET_BOOLEAN_TRUE(tv_val);
+ return;
+ } else if (d == 1.0) {
+ DUK_DDD(DUK_DDDPRINT("inlined lnot: !1 -> false"));
+ DUK_TVAL_SET_BOOLEAN_FALSE(tv_val);
+ return;
+ }
+ } else if (DUK_TVAL_IS_BOOLEAN(tv_val)) {
+ duk_small_int_t v;
+ v = DUK_TVAL_GET_BOOLEAN(tv_val);
+ DUK_DDD(DUK_DDDPRINT("inlined lnot boolean: %ld", (long) v));
+ DUK_ASSERT(v == 0 || v == 1);
+ DUK_TVAL_SET_BOOLEAN(tv_val, v ^ 0x01);
+ return;
+ }
+ }
+ args = (DUK_EXTRAOP_LNOT << 8) + 0;
+ goto unary_extraop;
+ }
+
+ } /* end switch */
+
+ DUK_ERROR_SYNTAX(thr, DUK_STR_PARSE_ERROR);
+ return;
+
+ unary_extraop:
+ {
+ /* Note: must coerce to a (writable) temp register, so that e.g. "!x" where x
+ * is a reg-mapped variable works correctly (does not mutate the variable register).
+ */
+
+ duk_reg_t reg_temp;
+ reg_temp = duk__ivalue_toregconst_raw(comp_ctx, res, -1 /*forced_reg*/, DUK__IVAL_FLAG_REQUIRE_TEMP /*flags*/);
+ duk__emit_extraop_bc(comp_ctx,
+ (args >> 8),
+ (duk_regconst_t) reg_temp);
+ res->t = DUK_IVAL_PLAIN;
+ res->x1.t = DUK_ISPEC_REGCONST;
+ res->x1.regconst = (duk_regconst_t) reg_temp;
+ return;
+ }
+
+ preincdec:
+ {
+ /* preincrement and predecrement */
+ duk_reg_t reg_res;
+ duk_small_uint_t args_op = args >> 8;
+
+ /* Specific assumptions for opcode numbering. */
+ DUK_ASSERT(DUK_OP_PREINCR + 4 == DUK_OP_PREINCV);
+ DUK_ASSERT(DUK_OP_PREDECR + 4 == DUK_OP_PREDECV);
+ DUK_ASSERT(DUK_OP_PREINCR + 8 == DUK_OP_PREINCP);
+ DUK_ASSERT(DUK_OP_PREDECR + 8 == DUK_OP_PREDECP);
+
+ reg_res = DUK__ALLOCTEMP(comp_ctx);
+
+ duk__expr(comp_ctx, res, DUK__BP_MULTIPLICATIVE /*rbp_flags*/); /* UnaryExpression */
+ if (res->t == DUK_IVAL_VAR) {
+ duk_hstring *h_varname;
+ duk_reg_t reg_varbind;
+ duk_regconst_t rc_varname;
+
+ h_varname = duk_get_hstring(ctx, res->x1.valstack_idx);
+ DUK_ASSERT(h_varname != NULL);
+
+ if (duk__hstring_is_eval_or_arguments_in_strict_mode(comp_ctx, h_varname)) {
+ goto syntax_error;
+ }
+
+ duk_dup(ctx, res->x1.valstack_idx);
+ if (duk__lookup_lhs(comp_ctx, ®_varbind, &rc_varname)) {
+ duk__emit_a_bc(comp_ctx,
+ args_op, /* e.g. DUK_OP_PREINCR */
+ (duk_regconst_t) reg_res,
+ (duk_regconst_t) reg_varbind);
+ } else {
+ duk__emit_a_bc(comp_ctx,
+ args_op + 4, /* e.g. DUK_OP_PREINCV */
+ (duk_regconst_t) reg_res,
+ rc_varname);
+ }
+
+ DUK_DDD(DUK_DDDPRINT("preincdec to '%!O' -> reg_varbind=%ld, rc_varname=%ld",
+ (duk_heaphdr *) h_varname, (long) reg_varbind, (long) rc_varname));
+ } else if (res->t == DUK_IVAL_PROP) {
+ duk_reg_t reg_obj; /* allocate to reg only (not const) */
+ duk_regconst_t rc_key;
+ reg_obj = duk__ispec_toregconst_raw(comp_ctx, &res->x1, -1 /*forced_reg*/, 0 /*flags*/); /* don't allow const */
+ rc_key = duk__ispec_toregconst_raw(comp_ctx, &res->x2, -1 /*forced_reg*/, DUK__IVAL_FLAG_ALLOW_CONST /*flags*/);
+ duk__emit_a_b_c(comp_ctx,
+ args_op + 8, /* e.g. DUK_OP_PREINCP */
+ (duk_regconst_t) reg_res,
+ (duk_regconst_t) reg_obj,
+ rc_key);
+ } else {
+ /* Technically return value is not needed because INVLHS will
+ * unconditially throw a ReferenceError. Coercion is necessary
+ * for proper semantics (consider ToNumber() called for an object).
+ * Use DUK_EXTRAOP_UNP with a dummy register to get ToNumber().
+ */
+
+ duk__ivalue_toforcedreg(comp_ctx, res, reg_res);
+ duk__emit_extraop_bc(comp_ctx,
+ DUK_EXTRAOP_UNP,
+ reg_res); /* for side effects, result ignored */
+ duk__emit_extraop_only(comp_ctx,
+ DUK_EXTRAOP_INVLHS);
+ }
+ res->t = DUK_IVAL_PLAIN;
+ res->x1.t = DUK_ISPEC_REGCONST;
+ res->x1.regconst = (duk_regconst_t) reg_res;
+ DUK__SETTEMP(comp_ctx, reg_res + 1);
+ return;
+ }
+
+ plain_value:
+ {
+ /* Stack top contains plain value */
+ res->t = DUK_IVAL_PLAIN;
+ res->x1.t = DUK_ISPEC_VALUE;
+ duk_replace(ctx, res->x1.valstack_idx);
+ return;
+ }
+
+ syntax_error:
+ DUK_ERROR_SYNTAX(thr, DUK_STR_INVALID_EXPRESSION);
+}
+
+/* XXX: add flag to indicate whether caller cares about return value; this
+ * affects e.g. handling of assignment expressions. This change needs API
+ * changes elsewhere too.
+ */
+DUK_LOCAL void duk__expr_led(duk_compiler_ctx *comp_ctx, duk_ivalue *left, duk_ivalue *res) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_token *tk;
+ duk_small_int_t tok;
+ duk_uint32_t args; /* temp variable to pass constants and flags to shared code */
+
+ /*
+ * ctx->prev_token token to process with duk__expr_led()
+ * ctx->curr_token updated by caller
+ */
+
+ comp_ctx->curr_func.led_count++;
+
+ /* The token in the switch has already been eaten here */
+ tk = &comp_ctx->prev_token;
+ tok = tk->t;
+
+ DUK_DDD(DUK_DDDPRINT("duk__expr_led(), prev_token.t=%ld, allow_in=%ld, paren_level=%ld",
+ (long) tk->t, (long) comp_ctx->curr_func.allow_in, (long) comp_ctx->curr_func.paren_level));
+
+ /* XXX: default priority for infix operators is duk__expr_lbp(tok) -> get it here? */
+
+ switch (tok) {
+
+ /* PRIMARY EXPRESSIONS */
+
+ case DUK_TOK_PERIOD: {
+ /* Property access expressions are critical for correct LHS ordering,
+ * see comments in duk__expr()!
+ *
+ * A conservative approach would be to use duk__ivalue_totempconst()
+ * for 'left'. However, allowing a reg-bound variable seems safe here
+ * and is nice because "foo.bar" is a common expression. If the ivalue
+ * is used in an expression a GETPROP will occur before any changes to
+ * the base value can occur. If the ivalue is used as an assignment
+ * LHS, the assignment code will ensure the base value is safe from
+ * RHS mutation.
+ */
+
+ /* XXX: This now coerces an identifier into a GETVAR to a temp, which
+ * causes an extra LDREG in call setup. It's sufficient to coerce to a
+ * unary ivalue?
+ */
+ duk__ivalue_toplain(comp_ctx, left);
+
+ /* NB: must accept reserved words as property name */
+ if (comp_ctx->curr_token.t_nores != DUK_TOK_IDENTIFIER) {
+ DUK_ERROR_SYNTAX(thr, DUK_STR_EXPECTED_IDENTIFIER);
+ }
+
+ res->t = DUK_IVAL_PROP;
+ duk__copy_ispec(comp_ctx, &left->x1, &res->x1); /* left.x1 -> res.x1 */
+ DUK_ASSERT(comp_ctx->curr_token.str1 != NULL);
+ duk_push_hstring(ctx, comp_ctx->curr_token.str1);
+ duk_replace(ctx, res->x2.valstack_idx);
+ res->x2.t = DUK_ISPEC_VALUE;
+
+ /* special RegExp literal handling after IdentifierName */
+ comp_ctx->curr_func.reject_regexp_in_adv = 1;
+
+ duk__advance(comp_ctx);
+ return;
+ }
+ case DUK_TOK_LBRACKET: {
+ /* Property access expressions are critical for correct LHS ordering,
+ * see comments in duk__expr()!
+ */
+
+ /* XXX: optimize temp reg use */
+ /* XXX: similar coercion issue as in DUK_TOK_PERIOD */
+ /* XXX: coerce to regs? it might be better for enumeration use, where the
+ * same PROP ivalue is used multiple times. Or perhaps coerce PROP further
+ * there?
+ */
+ /* XXX: for simple cases like x['y'] an unnecessary LDREG is
+ * emitted for the base value; could avoid it if we knew that
+ * the key expression is safe (e.g. just a single literal).
+ */
+
+ /* The 'left' value must not be a register bound variable
+ * because it may be mutated during the rest of the expression
+ * and E5.1 Section 11.2.1 specifies the order of evaluation
+ * so that the base value is evaluated first.
+ * See: test-bug-nested-prop-mutate.js.
+ */
+ duk__ivalue_totempconst(comp_ctx, left);
+ duk__expr_toplain(comp_ctx, res, DUK__BP_FOR_EXPR /*rbp_flags*/); /* Expression, ']' terminates */
+ duk__advance_expect(comp_ctx, DUK_TOK_RBRACKET);
+
+ res->t = DUK_IVAL_PROP;
+ duk__copy_ispec(comp_ctx, &res->x1, &res->x2); /* res.x1 -> res.x2 */
+ duk__copy_ispec(comp_ctx, &left->x1, &res->x1); /* left.x1 -> res.x1 */
+ return;
+ }
+ case DUK_TOK_LPAREN: {
+ /* function call */
+ duk_reg_t reg_cs = DUK__ALLOCTEMPS(comp_ctx, 2);
+ duk_int_t nargs;
+ duk_small_uint_t call_flags = 0;
+
+ /*
+ * XXX: attempt to get the call result to "next temp" whenever
+ * possible to avoid unnecessary register shuffles.
+ *
+ * XXX: CSPROP (and CSREG) can overwrite the call target register, and save one temp,
+ * if the call target is a temporary register and at the top of the temp reg "stack".
+ */
+
+ /*
+ * Setup call: target and 'this' binding. Three cases:
+ *
+ * 1. Identifier base (e.g. "foo()")
+ * 2. Property base (e.g. "foo.bar()")
+ * 3. Register base (e.g. "foo()()"; i.e. when a return value is a function)
+ */
+
+ if (left->t == DUK_IVAL_VAR) {
+ duk_hstring *h_varname;
+ duk_reg_t reg_varbind;
+ duk_regconst_t rc_varname;
+
+ DUK_DDD(DUK_DDDPRINT("function call with identifier base"));
+
+ h_varname = duk_get_hstring(ctx, left->x1.valstack_idx);
+ DUK_ASSERT(h_varname != NULL);
+ if (h_varname == DUK_HTHREAD_STRING_EVAL(thr)) {
+ /* Potential direct eval call detected, flag the CALL
+ * so that a run-time "direct eval" check is made and
+ * special behavior may be triggered. Note that this
+ * does not prevent 'eval' from being register bound.
+ */
+ DUK_DDD(DUK_DDDPRINT("function call with identifier 'eval' "
+ "-> enabling EVALCALL flag, marking function "
+ "as may_direct_eval"));
+ call_flags |= DUK_BC_CALL_FLAG_EVALCALL;
+
+ comp_ctx->curr_func.may_direct_eval = 1;
+ }
+
+ duk_dup(ctx, left->x1.valstack_idx);
+ if (duk__lookup_lhs(comp_ctx, ®_varbind, &rc_varname)) {
+ duk__emit_a_b(comp_ctx,
+ DUK_OP_CSREG,
+ (duk_regconst_t) (reg_cs + 0),
+ (duk_regconst_t) reg_varbind);
+ } else {
+ duk__emit_a_b(comp_ctx,
+ DUK_OP_CSVAR,
+ (duk_regconst_t) (reg_cs + 0),
+ rc_varname);
+ }
+ } else if (left->t == DUK_IVAL_PROP) {
+ DUK_DDD(DUK_DDDPRINT("function call with property base"));
+
+ duk__ispec_toforcedreg(comp_ctx, &left->x1, reg_cs + 0); /* base */
+ duk__ispec_toforcedreg(comp_ctx, &left->x2, reg_cs + 1); /* key */
+ duk__emit_a_b_c(comp_ctx,
+ DUK_OP_CSPROP,
+ (duk_regconst_t) (reg_cs + 0),
+ (duk_regconst_t) (reg_cs + 0),
+ (duk_regconst_t) (reg_cs + 1)); /* in-place setup */
+ } else {
+ DUK_DDD(DUK_DDDPRINT("function call with register base"));
+
+ duk__ivalue_toforcedreg(comp_ctx, left, reg_cs + 0);
+ duk__emit_a_b(comp_ctx,
+ DUK_OP_CSREG,
+ (duk_regconst_t) (reg_cs + 0),
+ (duk_regconst_t) (reg_cs + 0)); /* in-place setup */
+ }
+
+ DUK__SETTEMP(comp_ctx, reg_cs + 2);
+ nargs = duk__parse_arguments(comp_ctx, res); /* parse args starting from "next temp" */
+
+ /* Tailcalls are handled by back-patching the TAILCALL flag to the
+ * already emitted instruction later (in return statement parser).
+ * Since A and C have a special meaning here, they cannot be "shuffled".
+ */
+
+ duk__emit_a_b_c(comp_ctx,
+ DUK_OP_CALL | DUK__EMIT_FLAG_NO_SHUFFLE_A | DUK__EMIT_FLAG_NO_SHUFFLE_C,
+ (duk_regconst_t) call_flags /*flags*/,
+ (duk_regconst_t) reg_cs /*basereg*/,
+ (duk_regconst_t) nargs /*numargs*/);
+ DUK__SETTEMP(comp_ctx, reg_cs + 1); /* result in csreg */
+
+ res->t = DUK_IVAL_PLAIN;
+ res->x1.t = DUK_ISPEC_REGCONST;
+ res->x1.regconst = (duk_regconst_t) reg_cs;
+ return;
+ }
+
+ /* POSTFIX EXPRESSION */
+
+ case DUK_TOK_INCREMENT: {
+ args = (DUK_OP_POSTINCR << 8) + 0;
+ goto postincdec;
+ }
+ case DUK_TOK_DECREMENT: {
+ args = (DUK_OP_POSTDECR << 8) + 0;
+ goto postincdec;
+ }
+
+ /* MULTIPLICATIVE EXPRESSION */
+
+ case DUK_TOK_MUL: {
+ args = (DUK_OP_MUL << 8) + DUK__BP_MULTIPLICATIVE; /* UnaryExpression */
+ goto binary;
+ }
+ case DUK_TOK_DIV: {
+ args = (DUK_OP_DIV << 8) + DUK__BP_MULTIPLICATIVE; /* UnaryExpression */
+ goto binary;
+ }
+ case DUK_TOK_MOD: {
+ args = (DUK_OP_MOD << 8) + DUK__BP_MULTIPLICATIVE; /* UnaryExpression */
+ goto binary;
+ }
+
+ /* ADDITIVE EXPRESSION */
+
+ case DUK_TOK_ADD: {
+ args = (DUK_OP_ADD << 8) + DUK__BP_ADDITIVE; /* MultiplicativeExpression */
+ goto binary;
+ }
+ case DUK_TOK_SUB: {
+ args = (DUK_OP_SUB << 8) + DUK__BP_ADDITIVE; /* MultiplicativeExpression */
+ goto binary;
+ }
+
+ /* SHIFT EXPRESSION */
+
+ case DUK_TOK_ALSHIFT: {
+ /* << */
+ args = (DUK_OP_BASL << 8) + DUK__BP_SHIFT;
+ goto binary;
+ }
+ case DUK_TOK_ARSHIFT: {
+ /* >> */
+ args = (DUK_OP_BASR << 8) + DUK__BP_SHIFT;
+ goto binary;
+ }
+ case DUK_TOK_RSHIFT: {
+ /* >>> */
+ args = (DUK_OP_BLSR << 8) + DUK__BP_SHIFT;
+ goto binary;
+ }
+
+ /* RELATIONAL EXPRESSION */
+
+ case DUK_TOK_LT: {
+ /* < */
+ args = (DUK_OP_LT << 8) + DUK__BP_RELATIONAL;
+ goto binary;
+ }
+ case DUK_TOK_GT: {
+ args = (DUK_OP_GT << 8) + DUK__BP_RELATIONAL;
+ goto binary;
+ }
+ case DUK_TOK_LE: {
+ args = (DUK_OP_LE << 8) + DUK__BP_RELATIONAL;
+ goto binary;
+ }
+ case DUK_TOK_GE: {
+ args = (DUK_OP_GE << 8) + DUK__BP_RELATIONAL;
+ goto binary;
+ }
+ case DUK_TOK_INSTANCEOF: {
+ args = (1 << 16 /*is_extra*/) + (DUK_EXTRAOP_INSTOF << 8) + DUK__BP_RELATIONAL;
+ goto binary;
+ }
+ case DUK_TOK_IN: {
+ args = (1 << 16 /*is_extra*/) + (DUK_EXTRAOP_IN << 8) + DUK__BP_RELATIONAL;
+ goto binary;
+ }
+
+ /* EQUALITY EXPRESSION */
+
+ case DUK_TOK_EQ: {
+ args = (DUK_OP_EQ << 8) + DUK__BP_EQUALITY;
+ goto binary;
+ }
+ case DUK_TOK_NEQ: {
+ args = (DUK_OP_NEQ << 8) + DUK__BP_EQUALITY;
+ goto binary;
+ }
+ case DUK_TOK_SEQ: {
+ args = (DUK_OP_SEQ << 8) + DUK__BP_EQUALITY;
+ goto binary;
+ }
+ case DUK_TOK_SNEQ: {
+ args = (DUK_OP_SNEQ << 8) + DUK__BP_EQUALITY;
+ goto binary;
+ }
+
+ /* BITWISE EXPRESSIONS */
+
+ case DUK_TOK_BAND: {
+ args = (DUK_OP_BAND << 8) + DUK__BP_BAND;
+ goto binary;
+ }
+ case DUK_TOK_BXOR: {
+ args = (DUK_OP_BXOR << 8) + DUK__BP_BXOR;
+ goto binary;
+ }
+ case DUK_TOK_BOR: {
+ args = (DUK_OP_BOR << 8) + DUK__BP_BOR;
+ goto binary;
+ }
+
+ /* LOGICAL EXPRESSIONS */
+
+ case DUK_TOK_LAND: {
+ /* syntactically left-associative but parsed as right-associative */
+ args = (1 << 8) + DUK__BP_LAND - 1;
+ goto binary_logical;
+ }
+ case DUK_TOK_LOR: {
+ /* syntactically left-associative but parsed as right-associative */
+ args = (0 << 8) + DUK__BP_LOR - 1;
+ goto binary_logical;
+ }
+
+ /* CONDITIONAL EXPRESSION */
+
+ case DUK_TOK_QUESTION: {
+ /* XXX: common reg allocation need is to reuse a sub-expression's temp reg,
+ * but only if it really is a temp. Nothing fancy here now.
+ */
+ duk_reg_t reg_temp;
+ duk_int_t pc_jump1;
+ duk_int_t pc_jump2;
+
+ reg_temp = DUK__ALLOCTEMP(comp_ctx);
+ duk__ivalue_toforcedreg(comp_ctx, left, reg_temp);
+ duk__emit_if_true_skip(comp_ctx, reg_temp);
+ pc_jump1 = duk__emit_jump_empty(comp_ctx); /* jump to false */
+ duk__expr_toforcedreg(comp_ctx, res, DUK__BP_COMMA /*rbp_flags*/, reg_temp /*forced_reg*/); /* AssignmentExpression */
+ duk__advance_expect(comp_ctx, DUK_TOK_COLON);
+ pc_jump2 = duk__emit_jump_empty(comp_ctx); /* jump to end */
+ duk__patch_jump_here(comp_ctx, pc_jump1);
+ duk__expr_toforcedreg(comp_ctx, res, DUK__BP_COMMA /*rbp_flags*/, reg_temp /*forced_reg*/); /* AssignmentExpression */
+ duk__patch_jump_here(comp_ctx, pc_jump2);
+
+ DUK__SETTEMP(comp_ctx, reg_temp + 1);
+ res->t = DUK_IVAL_PLAIN;
+ res->x1.t = DUK_ISPEC_REGCONST;
+ res->x1.regconst = (duk_regconst_t) reg_temp;
+ return;
+ }
+
+ /* ASSIGNMENT EXPRESSION */
+
+ case DUK_TOK_EQUALSIGN: {
+ /*
+ * Assignments are right associative, allows e.g.
+ * a = 5;
+ * a += b = 9; // same as a += (b = 9)
+ * -> expression value 14, a = 14, b = 9
+ *
+ * Right associativiness is reflected in the BP for recursion,
+ * "-1" ensures assignment operations are allowed.
+ *
+ * XXX: just use DUK__BP_COMMA (i.e. no need for 2-step bp levels)?
+ */
+ args = (DUK_OP_NONE << 8) + DUK__BP_ASSIGNMENT - 1; /* DUK_OP_NONE marks a 'plain' assignment */
+ goto assign;
+ }
+ case DUK_TOK_ADD_EQ: {
+ /* right associative */
+ args = (DUK_OP_ADD << 8) + DUK__BP_ASSIGNMENT - 1;
+ goto assign;
+ }
+ case DUK_TOK_SUB_EQ: {
+ /* right associative */
+ args = (DUK_OP_SUB << 8) + DUK__BP_ASSIGNMENT - 1;
+ goto assign;
+ }
+ case DUK_TOK_MUL_EQ: {
+ /* right associative */
+ args = (DUK_OP_MUL << 8) + DUK__BP_ASSIGNMENT - 1;
+ goto assign;
+ }
+ case DUK_TOK_DIV_EQ: {
+ /* right associative */
+ args = (DUK_OP_DIV << 8) + DUK__BP_ASSIGNMENT - 1;
+ goto assign;
+ }
+ case DUK_TOK_MOD_EQ: {
+ /* right associative */
+ args = (DUK_OP_MOD << 8) + DUK__BP_ASSIGNMENT - 1;
+ goto assign;
+ }
+ case DUK_TOK_ALSHIFT_EQ: {
+ /* right associative */
+ args = (DUK_OP_BASL << 8) + DUK__BP_ASSIGNMENT - 1;
+ goto assign;
+ }
+ case DUK_TOK_ARSHIFT_EQ: {
+ /* right associative */
+ args = (DUK_OP_BASR << 8) + DUK__BP_ASSIGNMENT - 1;
+ goto assign;
+ }
+ case DUK_TOK_RSHIFT_EQ: {
+ /* right associative */
+ args = (DUK_OP_BLSR << 8) + DUK__BP_ASSIGNMENT - 1;
+ goto assign;
+ }
+ case DUK_TOK_BAND_EQ: {
+ /* right associative */
+ args = (DUK_OP_BAND << 8) + DUK__BP_ASSIGNMENT - 1;
+ goto assign;
+ }
+ case DUK_TOK_BOR_EQ: {
+ /* right associative */
+ args = (DUK_OP_BOR << 8) + DUK__BP_ASSIGNMENT - 1;
+ goto assign;
+ }
+ case DUK_TOK_BXOR_EQ: {
+ /* right associative */
+ args = (DUK_OP_BXOR << 8) + DUK__BP_ASSIGNMENT - 1;
+ goto assign;
+ }
+
+ /* COMMA */
+
+ case DUK_TOK_COMMA: {
+ /* right associative */
+
+ duk__ivalue_toplain_ignore(comp_ctx, left); /* need side effects, not value */
+ duk__expr_toplain(comp_ctx, res, DUK__BP_COMMA - 1 /*rbp_flags*/);
+
+ /* return 'res' (of right part) as our result */
+ return;
+ }
+
+ default: {
+ break;
+ }
+ }
+
+ DUK_D(DUK_DPRINT("parse error: unexpected token: %ld", (long) tok));
+ DUK_ERROR_SYNTAX(thr, DUK_STR_PARSE_ERROR);
+ return;
+
+#if 0
+ /* XXX: shared handling for 'duk__expr_lhs'? */
+ if (comp_ctx->curr_func.paren_level == 0 && XXX) {
+ comp_ctx->curr_func.duk__expr_lhs = 0;
+ }
+#endif
+
+ binary:
+ /*
+ * Shared handling of binary operations
+ *
+ * args = (is_extraop << 16) + (opcode << 8) + rbp
+ */
+ {
+ duk__ivalue_toplain(comp_ctx, left);
+ duk__expr_toplain(comp_ctx, res, args & 0xff /*rbp_flags*/);
+
+ /* combine left->x1 and res->x1 (right->x1, really) -> (left->x1 OP res->x1) */
+ DUK_ASSERT(left->t == DUK_IVAL_PLAIN);
+ DUK_ASSERT(res->t == DUK_IVAL_PLAIN);
+
+ res->t = (args >> 16) ? DUK_IVAL_ARITH_EXTRAOP : DUK_IVAL_ARITH;
+ res->op = (args >> 8) & 0xff;
+
+ res->x2.t = res->x1.t;
+ res->x2.regconst = res->x1.regconst;
+ duk_copy(ctx, res->x1.valstack_idx, res->x2.valstack_idx);
+
+ res->x1.t = left->x1.t;
+ res->x1.regconst = left->x1.regconst;
+ duk_copy(ctx, left->x1.valstack_idx, res->x1.valstack_idx);
+
+ DUK_DDD(DUK_DDDPRINT("binary op, res: t=%ld, x1.t=%ld, x1.regconst=0x%08lx, x2.t=%ld, x2.regconst=0x%08lx",
+ (long) res->t, (long) res->x1.t, (unsigned long) res->x1.regconst, (long) res->x2.t, (unsigned long) res->x2.regconst));
+ return;
+ }
+
+ binary_logical:
+ /*
+ * Shared handling for logical AND and logical OR.
+ *
+ * args = (truthval << 8) + rbp
+ *
+ * Truthval determines when to skip right-hand-side.
+ * For logical AND truthval=1, for logical OR truthval=0.
+ *
+ * See doc/compiler.rst for discussion on compiling logical
+ * AND and OR expressions. The approach here is very simplistic,
+ * generating extra jumps and multiple evaluations of truth values,
+ * but generates code on-the-fly with only local back-patching.
+ *
+ * Both logical AND and OR are syntactically left-associated.
+ * However, logical ANDs are compiled as right associative
+ * expressions, i.e. "A && B && C" as "A && (B && C)", to allow
+ * skip jumps to skip over the entire tail. Similarly for logical OR.
+ */
+
+ {
+ duk_reg_t reg_temp;
+ duk_int_t pc_jump;
+ duk_small_uint_t args_truthval = args >> 8;
+ duk_small_uint_t args_rbp = args & 0xff;
+
+ /* XXX: unoptimal use of temps, resetting */
+
+ reg_temp = DUK__ALLOCTEMP(comp_ctx);
+
+ duk__ivalue_toforcedreg(comp_ctx, left, reg_temp);
+ duk__emit_a_b(comp_ctx,
+ DUK_OP_IF | DUK__EMIT_FLAG_NO_SHUFFLE_A,
+ (duk_regconst_t) args_truthval,
+ (duk_regconst_t) reg_temp); /* skip jump conditionally */
+ pc_jump = duk__emit_jump_empty(comp_ctx);
+ duk__expr_toforcedreg(comp_ctx, res, args_rbp /*rbp_flags*/, reg_temp /*forced_reg*/);
+ duk__patch_jump_here(comp_ctx, pc_jump);
+
+ res->t = DUK_IVAL_PLAIN;
+ res->x1.t = DUK_ISPEC_REGCONST;
+ res->x1.regconst = (duk_regconst_t) reg_temp;
+ return;
+ }
+
+ assign:
+ /*
+ * Shared assignment expression handling
+ *
+ * args = (opcode << 8) + rbp
+ *
+ * If 'opcode' is DUK_OP_NONE, plain assignment without arithmetic.
+ * Syntactically valid left-hand-side forms which are not accepted as
+ * left-hand-side values (e.g. as in "f() = 1") must NOT cause a
+ * SyntaxError, but rather a run-time ReferenceError.
+ *
+ * When evaluating X <op>= Y, the LHS (X) is conceptually evaluated
+ * to a temporary first. The RHS is then evaluated. Finally, the
+ * <op> is applied to the initial value of RHS (not the value after
+ * RHS evaluation), and written to X. Doing so concretely generates
+ * inefficient code so we'd like to avoid the temporary when possible.
+ * See: https://github.com/svaarala/duktape/pull/992.
+ *
+ * The expression value (final LHS value, written to RHS) is
+ * conceptually copied into a fresh temporary so that it won't
+ * change even if the LHS/RHS values change in outer expressions.
+ * For example, it'd be generally incorrect for the expression value
+ * to be the RHS register binding, unless there's a guarantee that it
+ * won't change during further expression evaluation. Using the
+ * temporary concretely produces inefficient bytecode, so we try to
+ * avoid the extra temporary for some known-to-be-safe cases.
+ * Currently the only safe case we detect is a "top level assignment",
+ * for example "x = y + z;", where the assignment expression value is
+ * ignored.
+ * See: test-dev-assign-expr.js and test-bug-assign-mutate-gh381.js.
+ */
+
+ {
+ duk_small_uint_t args_op = args >> 8;
+ duk_small_uint_t args_rbp = args & 0xff;
+ duk_bool_t toplevel_assign;
+
+ /* XXX: here we need to know if 'left' is left-hand-side compatible.
+ * That information is no longer available from current expr parsing
+ * state; it would need to be carried into the 'left' ivalue or by
+ * some other means.
+ */
+
+ /* A top-level assignment is e.g. "x = y;". For these it's safe
+ * to use the RHS as-is as the expression value, even if the RHS
+ * is a reg-bound identifier. The RHS ('res') is right associative
+ * so it has consumed all other assignment level operations; the
+ * only relevant lower binding power construct is comma operator
+ * which will ignore the expression value provided here. Usually
+ * the top level assignment expression value is ignored, but it
+ * is relevant for e.g. eval code.
+ */
+ toplevel_assign = (comp_ctx->curr_func.nud_count == 1 && /* one token before */
+ comp_ctx->curr_func.led_count == 1); /* one operator (= assign) */
+ DUK_DDD(DUK_DDDPRINT("assignment: nud_count=%ld, led_count=%ld, toplevel_assign=%ld",
+ (long) comp_ctx->curr_func.nud_count,
+ (long) comp_ctx->curr_func.led_count,
+ (long) toplevel_assign));
+
+ if (left->t == DUK_IVAL_VAR) {
+ duk_hstring *h_varname;
+ duk_reg_t reg_varbind;
+ duk_regconst_t rc_varname;
+
+ DUK_ASSERT(left->x1.t == DUK_ISPEC_VALUE); /* LHS is already side effect free */
+
+ h_varname = duk_get_hstring(ctx, left->x1.valstack_idx);
+ DUK_ASSERT(h_varname != NULL);
+ if (duk__hstring_is_eval_or_arguments_in_strict_mode(comp_ctx, h_varname)) {
+ /* E5 Section 11.13.1 (and others for other assignments), step 4. */
+ goto syntax_error_lvalue;
+ }
+ duk_dup(ctx, left->x1.valstack_idx);
+ (void) duk__lookup_lhs(comp_ctx, ®_varbind, &rc_varname);
+
+ if (args_op == DUK_OP_NONE) {
+ duk__expr(comp_ctx, res, args_rbp /*rbp_flags*/);
+ if (toplevel_assign) {
+ /* Any 'res' will do. */
+ DUK_DDD(DUK_DDDPRINT("plain assignment, toplevel assign, use as is"));
+ } else {
+ /* 'res' must be a plain ivalue, and not register-bound variable. */
+ DUK_DDD(DUK_DDDPRINT("plain assignment, not toplevel assign, ensure not a reg-bound identifier"));
+ if (res->t != DUK_IVAL_PLAIN || (res->x1.t == DUK_ISPEC_REGCONST &&
+ (res->x1.regconst & DUK__CONST_MARKER) == 0 &&
+ !DUK__ISTEMP(comp_ctx, res->x1.regconst))) {
+ duk__ivalue_totempconst(comp_ctx, res);
+ }
+ }
+ } else {
+ /* For X <op>= Y we need to evaluate the pre-op
+ * value of X before evaluating the RHS: the RHS
+ * can change X, but when we do <op> we must use
+ * the pre-op value.
+ */
+ duk_reg_t reg_temp;
+
+ reg_temp = DUK__ALLOCTEMP(comp_ctx);
+
+ if (reg_varbind >= 0) {
+ duk_reg_t reg_res;
+ duk_reg_t reg_src;
+ duk_int_t pc_temp_load;
+ duk_int_t pc_before_rhs;
+ duk_int_t pc_after_rhs;
+
+ if (toplevel_assign) {
+ /* 'reg_varbind' is the operation result and can also
+ * become the expression value for top level assignments
+ * such as: "var x; x += y;".
+ */
+ DUK_DD(DUK_DDPRINT("<op>= expression is top level, write directly to reg_varbind"));
+ reg_res = reg_varbind;
+ } else {
+ /* Not safe to use 'reg_varbind' as assignment expression
+ * value, so go through a temp.
+ */
+ DUK_DD(DUK_DDPRINT("<op>= expression is not top level, write to reg_temp"));
+ reg_res = reg_temp; /* reg_res should be smallest possible */
+ reg_temp = DUK__ALLOCTEMP(comp_ctx);
+ }
+
+ /* Try to optimize X <op>= Y for reg-bound
+ * variables. Detect side-effect free RHS
+ * narrowly by seeing whether it emits code.
+ * If not, rewind the code emitter and overwrite
+ * the unnecessary temp reg load.
+ */
+
+ pc_temp_load = duk__get_current_pc(comp_ctx);
+ duk__emit_a_bc(comp_ctx,
+ DUK_OP_LDREG,
+ (duk_regconst_t) reg_temp,
+ reg_varbind);
+
+ pc_before_rhs = duk__get_current_pc(comp_ctx);
+ duk__expr_toregconst(comp_ctx, res, args_rbp /*rbp_flags*/);
+ DUK_ASSERT(res->t == DUK_IVAL_PLAIN && res->x1.t == DUK_ISPEC_REGCONST);
+ pc_after_rhs = duk__get_current_pc(comp_ctx);
+
+ DUK_DD(DUK_DDPRINT("pc_temp_load=%ld, pc_before_rhs=%ld, pc_after_rhs=%ld",
+ (long) pc_temp_load, (long) pc_before_rhs,
+ (long) pc_after_rhs));
+
+ if (pc_after_rhs == pc_before_rhs) {
+ /* Note: if the reg_temp load generated shuffling
+ * instructions, we may need to rewind more than
+ * one instruction, so use explicit PC computation.
+ */
+ DUK_DD(DUK_DDPRINT("rhs is side effect free, rewind and avoid unnecessary temp for reg-based <op>="));
+ DUK_BW_ADD_PTR(comp_ctx->thr, &comp_ctx->curr_func.bw_code, (pc_temp_load - pc_before_rhs) * sizeof(duk_compiler_instr));
+ reg_src = reg_varbind;
+ } else {
+ DUK_DD(DUK_DDPRINT("rhs evaluation emitted code, not sure if rhs is side effect free; use temp reg for LHS"));
+ reg_src = reg_temp;
+ }
+
+ duk__emit_a_b_c(comp_ctx,
+ args_op,
+ (duk_regconst_t) reg_res,
+ (duk_regconst_t) reg_src,
+ res->x1.regconst);
+
+ res->x1.regconst = (duk_regconst_t) reg_res;
+
+ /* Ensure compact use of temps. */
+ if (DUK__ISTEMP(comp_ctx, reg_res)) {
+ DUK__SETTEMP(comp_ctx, reg_res + 1);
+ }
+ } else {
+ /* When LHS is not register bound, always go through a
+ * temporary. No optimization for top level assignment.
+ */
+
+ duk__emit_a_bc(comp_ctx,
+ DUK_OP_GETVAR,
+ (duk_regconst_t) reg_temp,
+ rc_varname);
+
+ duk__expr_toregconst(comp_ctx, res, args_rbp /*rbp_flags*/);
+ DUK_ASSERT(res->t == DUK_IVAL_PLAIN && res->x1.t == DUK_ISPEC_REGCONST);
+
+ duk__emit_a_b_c(comp_ctx,
+ args_op,
+ (duk_regconst_t) reg_temp,
+ (duk_regconst_t) reg_temp,
+ res->x1.regconst);
+ res->x1.regconst = (duk_regconst_t) reg_temp;
+ }
+
+ DUK_ASSERT(res->t == DUK_IVAL_PLAIN && res->x1.t == DUK_ISPEC_REGCONST);
+ }
+
+ /* At this point 'res' holds the potential expression value.
+ * It can be basically any ivalue here, including a reg-bound
+ * identifier (if code above deems it safe) or a unary/binary
+ * operation. Operations must be resolved to a side effect free
+ * plain value, and the side effects must happen exactly once.
+ */
+
+ if (reg_varbind >= 0) {
+ if (res->t != DUK_IVAL_PLAIN) {
+ /* Resolve 'res' directly into the LHS binding, and use
+ * that as the expression value if safe. If not safe,
+ * resolve to a temp/const and copy to LHS.
+ */
+ if (toplevel_assign) {
+ duk__ivalue_toforcedreg(comp_ctx, res, (duk_int_t) reg_varbind);
+ } else {
+ duk__ivalue_totempconst(comp_ctx, res);
+ duk__copy_ivalue(comp_ctx, res, left); /* use 'left' as a temp */
+ duk__ivalue_toforcedreg(comp_ctx, left, (duk_int_t) reg_varbind);
+ }
+ } else {
+ /* Use 'res' as the expression value (it's side effect
+ * free and may be a plain value, a register, or a
+ * constant) and write it to the LHS binding too.
+ */
+ duk__copy_ivalue(comp_ctx, res, left); /* use 'left' as a temp */
+ duk__ivalue_toforcedreg(comp_ctx, left, (duk_int_t) reg_varbind);
+ }
+ } else {
+ /* Only a reg fits into 'A' so coerce 'res' into a register
+ * for PUTVAR.
+ *
+ * XXX: here the current A/B/C split is suboptimal: we could
+ * just use 9 bits for reg_res (and support constants) and 17
+ * instead of 18 bits for the varname const index.
+ */
+
+ duk__ivalue_toreg(comp_ctx, res);
+ duk__emit_a_bc(comp_ctx,
+ DUK_OP_PUTVAR | DUK__EMIT_FLAG_A_IS_SOURCE,
+ res->x1.regconst,
+ rc_varname);
+ }
+
+ /* 'res' contains expression value */
+ } else if (left->t == DUK_IVAL_PROP) {
+ /* E5 Section 11.13.1 (and others) step 4 never matches for prop writes -> no check */
+ duk_reg_t reg_obj;
+ duk_regconst_t rc_key;
+ duk_regconst_t rc_res;
+ duk_reg_t reg_temp;
+
+ /* Property access expressions ('a[b]') are critical to correct
+ * LHS evaluation ordering, see test-dev-assign-eval-order*.js.
+ * We must make sure that the LHS target slot (base object and
+ * key) don't change during RHS evaluation. The only concrete
+ * problem is a register reference to a variable-bound register
+ * (i.e., non-temp). Require temp regs for both key and base.
+ *
+ * Don't allow a constant for the object (even for a number
+ * etc), as it goes into the 'A' field of the opcode.
+ */
+
+ reg_obj = duk__ispec_toregconst_raw(comp_ctx,
+ &left->x1,
+ -1 /*forced_reg*/,
+ DUK__IVAL_FLAG_REQUIRE_TEMP /*flags*/);
+
+ rc_key = duk__ispec_toregconst_raw(comp_ctx,
+ &left->x2,
+ -1 /*forced_reg*/,
+ DUK__IVAL_FLAG_REQUIRE_TEMP | DUK__IVAL_FLAG_ALLOW_CONST /*flags*/);
+
+ /* Evaluate RHS only when LHS is safe. */
+
+ if (args_op == DUK_OP_NONE) {
+ duk__expr_toregconst(comp_ctx, res, args_rbp /*rbp_flags*/);
+ DUK_ASSERT(res->t == DUK_IVAL_PLAIN && res->x1.t == DUK_ISPEC_REGCONST);
+ rc_res = res->x1.regconst;
+ } else {
+ reg_temp = DUK__ALLOCTEMP(comp_ctx);
+ duk__emit_a_b_c(comp_ctx,
+ DUK_OP_GETPROP,
+ (duk_regconst_t) reg_temp,
+ (duk_regconst_t) reg_obj,
+ rc_key);
+
+ duk__expr_toregconst(comp_ctx, res, args_rbp /*rbp_flags*/);
+ DUK_ASSERT(res->t == DUK_IVAL_PLAIN && res->x1.t == DUK_ISPEC_REGCONST);
+
+ duk__emit_a_b_c(comp_ctx,
+ args_op,
+ (duk_regconst_t) reg_temp,
+ (duk_regconst_t) reg_temp,
+ res->x1.regconst);
+ rc_res = (duk_regconst_t) reg_temp;
+ }
+
+ duk__emit_a_b_c(comp_ctx,
+ DUK_OP_PUTPROP | DUK__EMIT_FLAG_A_IS_SOURCE,
+ (duk_regconst_t) reg_obj,
+ rc_key,
+ rc_res);
+
+ res->t = DUK_IVAL_PLAIN;
+ res->x1.t = DUK_ISPEC_REGCONST;
+ res->x1.regconst = rc_res;
+ } else {
+ /* No support for lvalues returned from new or function call expressions.
+ * However, these must NOT cause compile-time SyntaxErrors, but run-time
+ * ReferenceErrors. Both left and right sides of the assignment must be
+ * evaluated before throwing a ReferenceError. For instance:
+ *
+ * f() = g();
+ *
+ * must result in f() being evaluated, then g() being evaluated, and
+ * finally, a ReferenceError being thrown. See E5 Section 11.13.1.
+ */
+
+ duk_regconst_t rc_res;
+
+ /* First evaluate LHS fully to ensure all side effects are out. */
+ duk__ivalue_toplain_ignore(comp_ctx, left);
+
+ /* Then evaluate RHS fully (its value becomes the expression value too).
+ * Technically we'd need the side effect safety check here too, but because
+ * we always throw using INVLHS the result doesn't matter.
+ */
+ rc_res = duk__expr_toregconst(comp_ctx, res, args_rbp /*rbp_flags*/);
+
+ duk__emit_extraop_only(comp_ctx,
+ DUK_EXTRAOP_INVLHS);
+
+ res->t = DUK_IVAL_PLAIN;
+ res->x1.t = DUK_ISPEC_REGCONST;
+ res->x1.regconst = rc_res;
+ }
+
+ return;
+ }
+
+ postincdec:
+ {
+ /*
+ * Post-increment/decrement will return the original value as its
+ * result value. However, even that value will be coerced using
+ * ToNumber() which is quite awkward. Specific bytecode opcodes
+ * are used to handle these semantics.
+ *
+ * Note that post increment/decrement has a "no LineTerminator here"
+ * restriction. This is handled by duk__expr_lbp(), which forcibly terminates
+ * the previous expression if a LineTerminator occurs before '++'/'--'.
+ */
+
+ duk_reg_t reg_res;
+ duk_small_uint_t args_op = args >> 8;
+
+ /* Specific assumptions for opcode numbering. */
+ DUK_ASSERT(DUK_OP_POSTINCR + 4 == DUK_OP_POSTINCV);
+ DUK_ASSERT(DUK_OP_POSTDECR + 4 == DUK_OP_POSTDECV);
+ DUK_ASSERT(DUK_OP_POSTINCR + 8 == DUK_OP_POSTINCP);
+ DUK_ASSERT(DUK_OP_POSTDECR + 8 == DUK_OP_POSTDECP);
+
+ reg_res = DUK__ALLOCTEMP(comp_ctx);
+
+ if (left->t == DUK_IVAL_VAR) {
+ duk_hstring *h_varname;
+ duk_reg_t reg_varbind;
+ duk_regconst_t rc_varname;
+
+ h_varname = duk_get_hstring(ctx, left->x1.valstack_idx);
+ DUK_ASSERT(h_varname != NULL);
+
+ if (duk__hstring_is_eval_or_arguments_in_strict_mode(comp_ctx, h_varname)) {
+ goto syntax_error;
+ }
+
+ duk_dup(ctx, left->x1.valstack_idx);
+ if (duk__lookup_lhs(comp_ctx, ®_varbind, &rc_varname)) {
+ duk__emit_a_bc(comp_ctx,
+ args_op, /* e.g. DUK_OP_POSTINCR */
+ (duk_regconst_t) reg_res,
+ (duk_regconst_t) reg_varbind);
+ } else {
+ duk__emit_a_bc(comp_ctx,
+ args_op + 4, /* e.g. DUK_OP_POSTINCV */
+ (duk_regconst_t) reg_res,
+ rc_varname);
+ }
+
+ DUK_DDD(DUK_DDDPRINT("postincdec to '%!O' -> reg_varbind=%ld, rc_varname=%ld",
+ (duk_heaphdr *) h_varname, (long) reg_varbind, (long) rc_varname));
+ } else if (left->t == DUK_IVAL_PROP) {
+ duk_reg_t reg_obj; /* allocate to reg only (not const) */
+ duk_regconst_t rc_key;
+
+ reg_obj = duk__ispec_toregconst_raw(comp_ctx, &left->x1, -1 /*forced_reg*/, 0 /*flags*/); /* don't allow const */
+ rc_key = duk__ispec_toregconst_raw(comp_ctx, &left->x2, -1 /*forced_reg*/, DUK__IVAL_FLAG_ALLOW_CONST /*flags*/);
+ duk__emit_a_b_c(comp_ctx,
+ args_op + 8, /* e.g. DUK_OP_POSTINCP */
+ (duk_regconst_t) reg_res,
+ (duk_regconst_t) reg_obj,
+ rc_key);
+ } else {
+ /* Technically return value is not needed because INVLHS will
+ * unconditially throw a ReferenceError. Coercion is necessary
+ * for proper semantics (consider ToNumber() called for an object).
+ * Use DUK_EXTRAOP_UNP with a dummy register to get ToNumber().
+ */
+ duk__ivalue_toforcedreg(comp_ctx, left, reg_res);
+ duk__emit_extraop_bc(comp_ctx,
+ DUK_EXTRAOP_UNP,
+ reg_res); /* for side effects, result ignored */
+ duk__emit_extraop_only(comp_ctx,
+ DUK_EXTRAOP_INVLHS);
+ }
+
+ res->t = DUK_IVAL_PLAIN;
+ res->x1.t = DUK_ISPEC_REGCONST;
+ res->x1.regconst = (duk_regconst_t) reg_res;
+ DUK__SETTEMP(comp_ctx, reg_res + 1);
+ return;
+ }
+
+ syntax_error:
+ DUK_ERROR_SYNTAX(thr, DUK_STR_INVALID_EXPRESSION);
+ return;
+
+ syntax_error_lvalue:
+ DUK_ERROR_SYNTAX(thr, DUK_STR_INVALID_LVALUE);
+ return;
+}
+
+DUK_LOCAL duk_small_uint_t duk__expr_lbp(duk_compiler_ctx *comp_ctx) {
+ duk_small_int_t tok = comp_ctx->curr_token.t;
+
+ DUK_ASSERT(tok >= DUK_TOK_MINVAL && tok <= DUK_TOK_MAXVAL);
+ DUK_ASSERT(sizeof(duk__token_lbp) == DUK_TOK_MAXVAL + 1);
+
+ /* XXX: integrate support for this into led() instead?
+ * Similar issue as post-increment/post-decrement.
+ */
+
+ /* prevent duk__expr_led() by using a binding power less than anything valid */
+ if (tok == DUK_TOK_IN && !comp_ctx->curr_func.allow_in) {
+ return 0;
+ }
+
+ if ((tok == DUK_TOK_DECREMENT || tok == DUK_TOK_INCREMENT) &&
+ (comp_ctx->curr_token.lineterm)) {
+ /* '++' or '--' in a post-increment/decrement position,
+ * and a LineTerminator occurs between the operator and
+ * the preceding expression. Force the previous expr
+ * to terminate, in effect treating e.g. "a,b\n++" as
+ * "a,b;++" (= SyntaxError).
+ */
+ return 0;
+ }
+
+ return DUK__TOKEN_LBP_GET_BP(duk__token_lbp[tok]); /* format is bit packed */
+}
+
+/*
+ * Expression parsing.
+ *
+ * Upon entry to 'expr' and its variants, 'curr_tok' is assumed to be the
+ * first token of the expression. Upon exit, 'curr_tok' will be the first
+ * token not part of the expression (e.g. semicolon terminating an expression
+ * statement).
+ */
+
+#define DUK__EXPR_RBP_MASK 0xff
+#define DUK__EXPR_FLAG_REJECT_IN (1 << 8) /* reject 'in' token (used for for-in) */
+#define DUK__EXPR_FLAG_ALLOW_EMPTY (1 << 9) /* allow empty expression */
+#define DUK__EXPR_FLAG_REQUIRE_INIT (1 << 10) /* require initializer for var/const */
+
+/* main expression parser function */
+DUK_LOCAL void duk__expr(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_ivalue tmp_alloc; /* 'res' is used for "left", and 'tmp' for "right" */
+ duk_ivalue *tmp = &tmp_alloc;
+ duk_small_uint_t rbp;
+
+ DUK__RECURSION_INCREASE(comp_ctx, thr);
+
+ duk_require_stack(ctx, DUK__PARSE_EXPR_SLOTS);
+
+ /* filter out flags from exprtop rbp_flags here to save space */
+ rbp = rbp_flags & DUK__EXPR_RBP_MASK;
+
+ DUK_DDD(DUK_DDDPRINT("duk__expr(), rbp_flags=%ld, rbp=%ld, allow_in=%ld, paren_level=%ld",
+ (long) rbp_flags, (long) rbp, (long) comp_ctx->curr_func.allow_in,
+ (long) comp_ctx->curr_func.paren_level));
+
+ DUK_MEMZERO(&tmp_alloc, sizeof(tmp_alloc));
+ tmp->x1.valstack_idx = duk_get_top(ctx);
+ tmp->x2.valstack_idx = tmp->x1.valstack_idx + 1;
+ duk_push_undefined(ctx);
+ duk_push_undefined(ctx);
+
+ /* XXX: where to release temp regs in intermediate expressions?
+ * e.g. 1+2+3 -> don't inflate temp register count when parsing this.
+ * that particular expression temp regs can be forced here.
+ */
+
+ /* XXX: increase ctx->expr_tokens here for every consumed token
+ * (this would be a nice statistic)?
+ */
+
+ if (comp_ctx->curr_token.t == DUK_TOK_SEMICOLON || comp_ctx->curr_token.t == DUK_TOK_RPAREN) {
+ /* XXX: possibly incorrect handling of empty expression */
+ DUK_DDD(DUK_DDDPRINT("empty expression"));
+ if (!(rbp_flags & DUK__EXPR_FLAG_ALLOW_EMPTY)) {
+ DUK_ERROR_SYNTAX(thr, DUK_STR_EMPTY_EXPR_NOT_ALLOWED);
+ }
+ res->t = DUK_IVAL_PLAIN;
+ res->x1.t = DUK_ISPEC_VALUE;
+ duk_push_undefined(ctx);
+ duk_replace(ctx, res->x1.valstack_idx);
+ goto cleanup;
+ }
+
+ duk__advance(comp_ctx);
+ duk__expr_nud(comp_ctx, res); /* reuse 'res' as 'left' */
+ while (rbp < duk__expr_lbp(comp_ctx)) {
+ duk__advance(comp_ctx);
+ duk__expr_led(comp_ctx, res, tmp);
+ duk__copy_ivalue(comp_ctx, tmp, res); /* tmp -> res */
+ }
+
+ cleanup:
+ /* final result is already in 'res' */
+
+ duk_pop_2(ctx);
+
+ DUK__RECURSION_DECREASE(comp_ctx, thr);
+}
+
+DUK_LOCAL void duk__exprtop(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags) {
+ duk_hthread *thr = comp_ctx->thr;
+
+ /* Note: these variables must reside in 'curr_func' instead of the global
+ * context: when parsing function expressions, expression parsing is nested.
+ */
+ comp_ctx->curr_func.nud_count = 0;
+ comp_ctx->curr_func.led_count = 0;
+ comp_ctx->curr_func.paren_level = 0;
+ comp_ctx->curr_func.expr_lhs = 1;
+ comp_ctx->curr_func.allow_in = (rbp_flags & DUK__EXPR_FLAG_REJECT_IN ? 0 : 1);
+
+ duk__expr(comp_ctx, res, rbp_flags);
+
+ if (!(rbp_flags & DUK__EXPR_FLAG_ALLOW_EMPTY) && duk__expr_is_empty(comp_ctx)) {
+ DUK_ERROR_SYNTAX(thr, DUK_STR_EMPTY_EXPR_NOT_ALLOWED);
+ }
+}
+
+/* A bunch of helpers (for size optimization) that combine duk__expr()/duk__exprtop()
+ * and result conversions.
+ *
+ * Each helper needs at least 2-3 calls to make it worth while to wrap.
+ */
+
+#if 0 /* unused */
+DUK_LOCAL duk_reg_t duk__expr_toreg(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags) {
+ duk__expr(comp_ctx, res, rbp_flags);
+ return duk__ivalue_toreg(comp_ctx, res);
+}
+#endif
+
+#if 0 /* unused */
+DUK_LOCAL duk_reg_t duk__expr_totemp(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags) {
+ duk__expr(comp_ctx, res, rbp_flags);
+ return duk__ivalue_totemp(comp_ctx, res);
+}
+#endif
+
+DUK_LOCAL void duk__expr_toforcedreg(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags, duk_reg_t forced_reg) {
+ DUK_ASSERT(forced_reg >= 0);
+ duk__expr(comp_ctx, res, rbp_flags);
+ duk__ivalue_toforcedreg(comp_ctx, res, forced_reg);
+}
+
+DUK_LOCAL duk_regconst_t duk__expr_toregconst(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags) {
+ duk__expr(comp_ctx, res, rbp_flags);
+ return duk__ivalue_toregconst(comp_ctx, res);
+}
+
+#if 0 /* unused */
+DUK_LOCAL duk_regconst_t duk__expr_totempconst(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags) {
+ duk__expr(comp_ctx, res, rbp_flags);
+ return duk__ivalue_totempconst(comp_ctx, res);
+}
+#endif
+
+DUK_LOCAL void duk__expr_toplain(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags) {
+ duk__expr(comp_ctx, res, rbp_flags);
+ duk__ivalue_toplain(comp_ctx, res);
+}
+
+DUK_LOCAL void duk__expr_toplain_ignore(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags) {
+ duk__expr(comp_ctx, res, rbp_flags);
+ duk__ivalue_toplain_ignore(comp_ctx, res);
+}
+
+DUK_LOCAL duk_reg_t duk__exprtop_toreg(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags) {
+ duk__exprtop(comp_ctx, res, rbp_flags);
+ return duk__ivalue_toreg(comp_ctx, res);
+}
+
+#if 0 /* unused */
+DUK_LOCAL duk_reg_t duk__exprtop_totemp(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags) {
+ duk__exprtop(comp_ctx, res, rbp_flags);
+ return duk__ivalue_totemp(comp_ctx, res);
+}
+#endif
+
+DUK_LOCAL void duk__exprtop_toforcedreg(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags, duk_reg_t forced_reg) {
+ DUK_ASSERT(forced_reg >= 0);
+ duk__exprtop(comp_ctx, res, rbp_flags);
+ duk__ivalue_toforcedreg(comp_ctx, res, forced_reg);
+}
+
+DUK_LOCAL duk_regconst_t duk__exprtop_toregconst(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t rbp_flags) {
+ duk__exprtop(comp_ctx, res, rbp_flags);
+ return duk__ivalue_toregconst(comp_ctx, res);
+}
+
+#if 0 /* unused */
+DUK_LOCAL void duk__exprtop_toplain_ignore(duk_compiler_ctx *comp_ctx, duk_ivalue *res, int rbp_flags) {
+ duk__exprtop(comp_ctx, res, rbp_flags);
+ duk__ivalue_toplain_ignore(comp_ctx, res);
+}
+#endif
+
+/*
+ * Parse an individual source element (top level statement) or a statement.
+ *
+ * Handles labeled statements automatically (peeling away labels before
+ * parsing an expression that follows the label(s)).
+ *
+ * Upon entry, 'curr_tok' contains the first token of the statement (parsed
+ * in "allow regexp literal" mode). Upon exit, 'curr_tok' contains the first
+ * token following the statement (if the statement has a terminator, this is
+ * the token after the terminator).
+ */
+
+#ifdef DUK__HAS_VAL
+#undef DUK__HAS_VAL
+#endif
+#ifdef DUK__HAS_TERM
+#undef DUK__HAS_TERM
+#endif
+#ifdef DUK__ALLOW_AUTO_SEMI_ALWAYS
+#undef DUK__ALLOW_AUTO_SEMI_ALWAYS
+#endif
+#ifdef DUK__STILL_PROLOGUE
+#undef DUK__STILL_PROLOGUE
+#endif
+#ifdef DUK__IS_TERMINAL
+#undef DUK__IS_TERMINAL
+#endif
+
+#define DUK__HAS_VAL (1 << 0) /* stmt has non-empty value */
+#define DUK__HAS_TERM (1 << 1) /* stmt has explicit/implicit semicolon terminator */
+#define DUK__ALLOW_AUTO_SEMI_ALWAYS (1 << 2) /* allow automatic semicolon even without lineterm (compatibility) */
+#define DUK__STILL_PROLOGUE (1 << 3) /* statement does not terminate directive prologue */
+#define DUK__IS_TERMINAL (1 << 4) /* statement is guaranteed to be terminal (control doesn't flow to next statement) */
+
+/* Parse a single variable declaration (e.g. "i" or "i=10"). A leading 'var'
+ * has already been eaten. These is no return value in 'res', it is used only
+ * as a temporary.
+ *
+ * When called from 'for-in' statement parser, the initializer expression must
+ * not allow the 'in' token. The caller supply additional expression parsing
+ * flags (like DUK__EXPR_FLAG_REJECT_IN) in 'expr_flags'.
+ *
+ * Finally, out_rc_varname and out_reg_varbind are updated to reflect where
+ * the identifier is bound:
+ *
+ * If register bound: out_reg_varbind >= 0, out_rc_varname == 0 (ignore)
+ * If not register bound: out_reg_varbind < 0, out_rc_varname >= 0
+ *
+ * These allow the caller to use the variable for further assignment, e.g.
+ * as is done in 'for-in' parsing.
+ */
+
+DUK_LOCAL void duk__parse_var_decl(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t expr_flags, duk_reg_t *out_reg_varbind, duk_regconst_t *out_rc_varname) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_hstring *h_varname;
+ duk_reg_t reg_varbind;
+ duk_regconst_t rc_varname;
+
+ /* assume 'var' has been eaten */
+
+ /* Note: Identifier rejects reserved words */
+ if (comp_ctx->curr_token.t != DUK_TOK_IDENTIFIER) {
+ goto syntax_error;
+ }
+ h_varname = comp_ctx->curr_token.str1;
+
+ DUK_ASSERT(h_varname != NULL);
+
+ /* strict mode restrictions (E5 Section 12.2.1) */
+ if (duk__hstring_is_eval_or_arguments_in_strict_mode(comp_ctx, h_varname)) {
+ goto syntax_error;
+ }
+
+ /* register declarations in first pass */
+ if (comp_ctx->curr_func.in_scanning) {
+ duk_uarridx_t n;
+ DUK_DDD(DUK_DDDPRINT("register variable declaration %!O in pass 1",
+ (duk_heaphdr *) h_varname));
+ n = (duk_uarridx_t) duk_get_length(ctx, comp_ctx->curr_func.decls_idx);
+ duk_push_hstring(ctx, h_varname);
+ duk_put_prop_index(ctx, comp_ctx->curr_func.decls_idx, n);
+ duk_push_int(ctx, DUK_DECL_TYPE_VAR + (0 << 8));
+ duk_put_prop_index(ctx, comp_ctx->curr_func.decls_idx, n + 1);
+ }
+
+ duk_push_hstring(ctx, h_varname); /* push before advancing to keep reachable */
+
+ /* register binding lookup is based on varmap (even in first pass) */
+ duk_dup_top(ctx);
+ (void) duk__lookup_lhs(comp_ctx, ®_varbind, &rc_varname);
+
+ duk__advance(comp_ctx); /* eat identifier */
+
+ if (comp_ctx->curr_token.t == DUK_TOK_EQUALSIGN) {
+ duk__advance(comp_ctx);
+
+ DUK_DDD(DUK_DDDPRINT("vardecl, assign to '%!O' -> reg_varbind=%ld, rc_varname=%ld",
+ (duk_heaphdr *) h_varname, (long) reg_varbind, (long) rc_varname));
+
+ duk__exprtop(comp_ctx, res, DUK__BP_COMMA | expr_flags /*rbp_flags*/); /* AssignmentExpression */
+
+ if (reg_varbind >= 0) {
+ duk__ivalue_toforcedreg(comp_ctx, res, reg_varbind);
+ } else {
+ duk_reg_t reg_val;
+ reg_val = duk__ivalue_toreg(comp_ctx, res);
+ duk__emit_a_bc(comp_ctx,
+ DUK_OP_PUTVAR | DUK__EMIT_FLAG_A_IS_SOURCE,
+ (duk_regconst_t) reg_val,
+ rc_varname);
+ }
+ } else {
+ if (expr_flags & DUK__EXPR_FLAG_REQUIRE_INIT) {
+ /* Used for minimal 'const': initializer required. */
+ goto syntax_error;
+ }
+ }
+
+ duk_pop(ctx); /* pop varname */
+
+ *out_rc_varname = rc_varname;
+ *out_reg_varbind = reg_varbind;
+
+ return;
+
+ syntax_error:
+ DUK_ERROR_SYNTAX(thr, DUK_STR_INVALID_VAR_DECLARATION);
+}
+
+DUK_LOCAL void duk__parse_var_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_small_uint_t expr_flags) {
+ duk_reg_t reg_varbind;
+ duk_regconst_t rc_varname;
+
+ duk__advance(comp_ctx); /* eat 'var' */
+
+ for (;;) {
+ /* rc_varname and reg_varbind are ignored here */
+ duk__parse_var_decl(comp_ctx, res, 0 | expr_flags, ®_varbind, &rc_varname);
+
+ if (comp_ctx->curr_token.t != DUK_TOK_COMMA) {
+ break;
+ }
+ duk__advance(comp_ctx);
+ }
+}
+
+DUK_LOCAL void duk__parse_for_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_int_t pc_label_site) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_int_t pc_v34_lhs; /* start variant 3/4 left-hand-side code (L1 in doc/compiler.rst example) */
+ duk_reg_t temp_reset; /* knock back "next temp" to this whenever possible */
+ duk_reg_t reg_temps; /* preallocated temporaries (2) for variants 3 and 4 */
+
+ DUK_DDD(DUK_DDDPRINT("start parsing a for/for-in statement"));
+
+ /* Two temporaries are preallocated here for variants 3 and 4 which need
+ * registers which are never clobbered by expressions in the loop
+ * (concretely: for the enumerator object and the next enumerated value).
+ * Variants 1 and 2 "release" these temps.
+ */
+
+ reg_temps = DUK__ALLOCTEMPS(comp_ctx, 2);
+
+ temp_reset = DUK__GETTEMP(comp_ctx);
+
+ /*
+ * For/for-in main variants are:
+ *
+ * 1. for (ExpressionNoIn_opt; Expression_opt; Expression_opt) Statement
+ * 2. for (var VariableDeclarationNoIn; Expression_opt; Expression_opt) Statement
+ * 3. for (LeftHandSideExpression in Expression) Statement
+ * 4. for (var VariableDeclarationNoIn in Expression) Statement
+ *
+ * Parsing these without arbitrary lookahead or backtracking is relatively
+ * tricky but we manage to do so for now.
+ *
+ * See doc/compiler.rst for a detailed discussion of control flow
+ * issues, evaluation order issues, etc.
+ */
+
+ duk__advance(comp_ctx); /* eat 'for' */
+ duk__advance_expect(comp_ctx, DUK_TOK_LPAREN);
+
+ DUK_DDD(DUK_DDDPRINT("detecting for/for-in loop variant, pc=%ld", (long) duk__get_current_pc(comp_ctx)));
+
+ /* a label site has been emitted by duk__parse_stmt() automatically
+ * (it will also emit the ENDLABEL).
+ */
+
+ if (comp_ctx->curr_token.t == DUK_TOK_VAR) {
+ /*
+ * Variant 2 or 4
+ */
+
+ duk_reg_t reg_varbind; /* variable binding register if register-bound (otherwise < 0) */
+ duk_regconst_t rc_varname; /* variable name reg/const, if variable not register-bound */
+
+ duk__advance(comp_ctx); /* eat 'var' */
+ duk__parse_var_decl(comp_ctx, res, DUK__EXPR_FLAG_REJECT_IN, ®_varbind, &rc_varname);
+ DUK__SETTEMP(comp_ctx, temp_reset);
+
+ if (comp_ctx->curr_token.t == DUK_TOK_IN) {
+ /*
+ * Variant 4
+ */
+
+ DUK_DDD(DUK_DDDPRINT("detected for variant 4: for (var VariableDeclarationNoIn in Expression) Statement"));
+ pc_v34_lhs = duk__get_current_pc(comp_ctx); /* jump is inserted here */
+ if (reg_varbind >= 0) {
+ duk__emit_a_bc(comp_ctx,
+ DUK_OP_LDREG,
+ (duk_regconst_t) reg_varbind,
+ (duk_regconst_t) (reg_temps + 0));
+ } else {
+ duk__emit_a_bc(comp_ctx,
+ DUK_OP_PUTVAR | DUK__EMIT_FLAG_A_IS_SOURCE,
+ (duk_regconst_t) (reg_temps + 0),
+ rc_varname);
+ }
+ goto parse_3_or_4;
+ } else {
+ /*
+ * Variant 2
+ */
+
+ DUK_DDD(DUK_DDDPRINT("detected for variant 2: for (var VariableDeclarationNoIn; Expression_opt; Expression_opt) Statement"));
+ for (;;) {
+ /* more initializers */
+ if (comp_ctx->curr_token.t != DUK_TOK_COMMA) {
+ break;
+ }
+ DUK_DDD(DUK_DDDPRINT("variant 2 has another variable initializer"));
+
+ duk__advance(comp_ctx); /* eat comma */
+ duk__parse_var_decl(comp_ctx, res, DUK__EXPR_FLAG_REJECT_IN, ®_varbind, &rc_varname);
+ }
+ goto parse_1_or_2;
+ }
+ } else {
+ /*
+ * Variant 1 or 3
+ */
+
+ pc_v34_lhs = duk__get_current_pc(comp_ctx); /* jump is inserted here (variant 3) */
+
+ /* Note that duk__exprtop() here can clobber any reg above current temp_next,
+ * so any loop variables (e.g. enumerator) must be "preallocated".
+ */
+
+ /* don't coerce yet to a plain value (variant 3 needs special handling) */
+ duk__exprtop(comp_ctx, res, DUK__BP_FOR_EXPR | DUK__EXPR_FLAG_REJECT_IN | DUK__EXPR_FLAG_ALLOW_EMPTY /*rbp_flags*/); /* Expression */
+ if (comp_ctx->curr_token.t == DUK_TOK_IN) {
+ /*
+ * Variant 3
+ */
+
+ /* XXX: need to determine LHS type, and check that it is LHS compatible */
+ DUK_DDD(DUK_DDDPRINT("detected for variant 3: for (LeftHandSideExpression in Expression) Statement"));
+ if (duk__expr_is_empty(comp_ctx)) {
+ goto syntax_error; /* LeftHandSideExpression does not allow empty expression */
+ }
+
+ if (res->t == DUK_IVAL_VAR) {
+ duk_reg_t reg_varbind;
+ duk_regconst_t rc_varname;
+
+ duk_dup(ctx, res->x1.valstack_idx);
+ if (duk__lookup_lhs(comp_ctx, ®_varbind, &rc_varname)) {
+ duk__emit_a_bc(comp_ctx,
+ DUK_OP_LDREG,
+ (duk_regconst_t) reg_varbind,
+ (duk_regconst_t) (reg_temps + 0));
+ } else {
+ duk__emit_a_bc(comp_ctx,
+ DUK_OP_PUTVAR | DUK__EMIT_FLAG_A_IS_SOURCE,
+ (duk_regconst_t) (reg_temps + 0),
+ rc_varname);
+ }
+ } else if (res->t == DUK_IVAL_PROP) {
+ /* Don't allow a constant for the object (even for a number etc), as
+ * it goes into the 'A' field of the opcode.
+ */
+ duk_reg_t reg_obj;
+ duk_regconst_t rc_key;
+ reg_obj = duk__ispec_toregconst_raw(comp_ctx, &res->x1, -1 /*forced_reg*/, 0 /*flags*/); /* don't allow const */
+ rc_key = duk__ispec_toregconst_raw(comp_ctx, &res->x2, -1 /*forced_reg*/, DUK__IVAL_FLAG_ALLOW_CONST /*flags*/);
+ duk__emit_a_b_c(comp_ctx,
+ DUK_OP_PUTPROP | DUK__EMIT_FLAG_A_IS_SOURCE,
+ (duk_regconst_t) reg_obj,
+ rc_key,
+ (duk_regconst_t) (reg_temps + 0));
+ } else {
+ duk__ivalue_toplain_ignore(comp_ctx, res); /* just in case */
+ duk__emit_extraop_only(comp_ctx,
+ DUK_EXTRAOP_INVLHS);
+ }
+ goto parse_3_or_4;
+ } else {
+ /*
+ * Variant 1
+ */
+
+ DUK_DDD(DUK_DDDPRINT("detected for variant 1: for (ExpressionNoIn_opt; Expression_opt; Expression_opt) Statement"));
+ duk__ivalue_toplain_ignore(comp_ctx, res);
+ goto parse_1_or_2;
+ }
+ }
+
+ parse_1_or_2:
+ /*
+ * Parse variant 1 or 2. The first part expression (which differs
+ * in the variants) has already been parsed and its code emitted.
+ *
+ * reg_temps + 0: unused
+ * reg_temps + 1: unused
+ */
+ {
+ duk_regconst_t rc_cond;
+ duk_int_t pc_l1, pc_l2, pc_l3, pc_l4;
+ duk_int_t pc_jumpto_l3, pc_jumpto_l4;
+ duk_bool_t expr_c_empty;
+
+ DUK_DDD(DUK_DDDPRINT("shared code for parsing variants 1 and 2"));
+
+ /* "release" preallocated temps since we won't need them */
+ temp_reset = reg_temps + 0;
+ DUK__SETTEMP(comp_ctx, temp_reset);
+
+ duk__advance_expect(comp_ctx, DUK_TOK_SEMICOLON);
+
+ pc_l1 = duk__get_current_pc(comp_ctx);
+ duk__exprtop(comp_ctx, res, DUK__BP_FOR_EXPR | DUK__EXPR_FLAG_ALLOW_EMPTY /*rbp_flags*/); /* Expression_opt */
+ if (duk__expr_is_empty(comp_ctx)) {
+ /* no need to coerce */
+ pc_jumpto_l3 = duk__emit_jump_empty(comp_ctx); /* to body */
+ pc_jumpto_l4 = -1; /* omitted */
+ } else {
+ rc_cond = duk__ivalue_toregconst(comp_ctx, res);
+ duk__emit_if_false_skip(comp_ctx, rc_cond);
+ pc_jumpto_l3 = duk__emit_jump_empty(comp_ctx); /* to body */
+ pc_jumpto_l4 = duk__emit_jump_empty(comp_ctx); /* to exit */
+ }
+ DUK__SETTEMP(comp_ctx, temp_reset);
+
+ duk__advance_expect(comp_ctx, DUK_TOK_SEMICOLON);
+
+ pc_l2 = duk__get_current_pc(comp_ctx);
+ duk__exprtop(comp_ctx, res, DUK__BP_FOR_EXPR | DUK__EXPR_FLAG_ALLOW_EMPTY /*rbp_flags*/); /* Expression_opt */
+ if (duk__expr_is_empty(comp_ctx)) {
+ /* no need to coerce */
+ expr_c_empty = 1;
+ /* JUMP L1 omitted */
+ } else {
+ duk__ivalue_toplain_ignore(comp_ctx, res);
+ expr_c_empty = 0;
+ duk__emit_jump(comp_ctx, pc_l1);
+ }
+ DUK__SETTEMP(comp_ctx, temp_reset);
+
+ duk__advance_expect(comp_ctx, DUK_TOK_RPAREN);
+
+ pc_l3 = duk__get_current_pc(comp_ctx);
+ duk__parse_stmt(comp_ctx, res, 0 /*allow_source_elem*/);
+ if (expr_c_empty) {
+ duk__emit_jump(comp_ctx, pc_l1);
+ } else {
+ duk__emit_jump(comp_ctx, pc_l2);
+ }
+ /* temp reset is not necessary after duk__parse_stmt(), which already does it */
+
+ pc_l4 = duk__get_current_pc(comp_ctx);
+
+ DUK_DDD(DUK_DDDPRINT("patching jumps: jumpto_l3: %ld->%ld, jumpto_l4: %ld->%ld, "
+ "break: %ld->%ld, continue: %ld->%ld",
+ (long) pc_jumpto_l3, (long) pc_l3, (long) pc_jumpto_l4, (long) pc_l4,
+ (long) (pc_label_site + 1), (long) pc_l4, (long) (pc_label_site + 2), (long) pc_l2));
+
+ duk__patch_jump(comp_ctx, pc_jumpto_l3, pc_l3);
+ duk__patch_jump(comp_ctx, pc_jumpto_l4, pc_l4);
+ duk__patch_jump(comp_ctx,
+ pc_label_site + 1,
+ pc_l4); /* break jump */
+ duk__patch_jump(comp_ctx,
+ pc_label_site + 2,
+ expr_c_empty ? pc_l1 : pc_l2); /* continue jump */
+ }
+ goto finished;
+
+ parse_3_or_4:
+ /*
+ * Parse variant 3 or 4.
+ *
+ * For variant 3 (e.g. "for (A in C) D;") the code for A (except the
+ * final property/variable write) has already been emitted. The first
+ * instruction of that code is at pc_v34_lhs; a JUMP needs to be inserted
+ * there to satisfy control flow needs.
+ *
+ * For variant 4, if the variable declaration had an initializer
+ * (e.g. "for (var A = B in C) D;") the code for the assignment
+ * (B) has already been emitted.
+ *
+ * Variables set before entering here:
+ *
+ * pc_v34_lhs: insert a "JUMP L2" here (see doc/compiler.rst example).
+ * reg_temps + 0: iteration target value (written to LHS)
+ * reg_temps + 1: enumerator object
+ */
+ {
+ duk_int_t pc_l1, pc_l2, pc_l3, pc_l4, pc_l5;
+ duk_int_t pc_jumpto_l2, pc_jumpto_l3, pc_jumpto_l4, pc_jumpto_l5;
+ duk_reg_t reg_target;
+
+ DUK_DDD(DUK_DDDPRINT("shared code for parsing variants 3 and 4, pc_v34_lhs=%ld", (long) pc_v34_lhs));
+
+ DUK__SETTEMP(comp_ctx, temp_reset);
+
+ /* First we need to insert a jump in the middle of previously
+ * emitted code to get the control flow right. No jumps can
+ * cross the position where the jump is inserted. See doc/compiler.rst
+ * for discussion on the intricacies of control flow and side effects
+ * for variants 3 and 4.
+ */
+
+ duk__insert_jump_entry(comp_ctx, pc_v34_lhs);
+ pc_jumpto_l2 = pc_v34_lhs; /* inserted jump */
+ pc_l1 = pc_v34_lhs + 1; /* +1, right after inserted jump */
+
+ /* The code for writing reg_temps + 0 to the left hand side has already
+ * been emitted.
+ */
+
+ pc_jumpto_l3 = duk__emit_jump_empty(comp_ctx); /* -> loop body */
+
+ duk__advance(comp_ctx); /* eat 'in' */
+
+ /* Parse enumeration target and initialize enumerator. For 'null' and 'undefined',
+ * INITENUM will creates a 'null' enumerator which works like an empty enumerator
+ * (E5 Section 12.6.4, step 3). Note that INITENUM requires the value to be in a
+ * register (constant not allowed).
+ */
+
+ pc_l2 = duk__get_current_pc(comp_ctx);
+ reg_target = duk__exprtop_toreg(comp_ctx, res, DUK__BP_FOR_EXPR /*rbp_flags*/); /* Expression */
+ duk__emit_extraop_b_c(comp_ctx,
+ DUK_EXTRAOP_INITENUM | DUK__EMIT_FLAG_B_IS_TARGET,
+ (duk_regconst_t) (reg_temps + 1),
+ (duk_regconst_t) reg_target);
+ pc_jumpto_l4 = duk__emit_jump_empty(comp_ctx);
+ DUK__SETTEMP(comp_ctx, temp_reset);
+
+ duk__advance_expect(comp_ctx, DUK_TOK_RPAREN);
+
+ pc_l3 = duk__get_current_pc(comp_ctx);
+ duk__parse_stmt(comp_ctx, res, 0 /*allow_source_elem*/);
+ /* temp reset is not necessary after duk__parse_stmt(), which already does it */
+
+ /* NEXTENUM needs a jump slot right after the main opcode.
+ * We need the code emitter to reserve the slot: if there's
+ * target shuffling, the target shuffle opcodes must happen
+ * after the jump slot (for NEXTENUM the shuffle opcodes are
+ * not needed if the enum is finished).
+ */
+ pc_l4 = duk__get_current_pc(comp_ctx);
+ duk__emit_extraop_b_c(comp_ctx,
+ DUK_EXTRAOP_NEXTENUM | DUK__EMIT_FLAG_B_IS_TARGET | DUK__EMIT_FLAG_RESERVE_JUMPSLOT,
+ (duk_regconst_t) (reg_temps + 0),
+ (duk_regconst_t) (reg_temps + 1));
+ pc_jumpto_l5 = comp_ctx->emit_jumpslot_pc; /* NEXTENUM jump slot: executed when enum finished */
+ duk__emit_jump(comp_ctx, pc_l1); /* jump to next loop, using reg_v34_iter as iterated value */
+
+ pc_l5 = duk__get_current_pc(comp_ctx);
+
+ /* XXX: since the enumerator may be a memory expensive object,
+ * perhaps clear it explicitly here? If so, break jump must
+ * go through this clearing operation.
+ */
+
+ DUK_DDD(DUK_DDDPRINT("patching jumps: jumpto_l2: %ld->%ld, jumpto_l3: %ld->%ld, "
+ "jumpto_l4: %ld->%ld, jumpto_l5: %ld->%ld, "
+ "break: %ld->%ld, continue: %ld->%ld",
+ (long) pc_jumpto_l2, (long) pc_l2, (long) pc_jumpto_l3, (long) pc_l3,
+ (long) pc_jumpto_l4, (long) pc_l4, (long) pc_jumpto_l5, (long) pc_l5,
+ (long) (pc_label_site + 1), (long) pc_l5, (long) (pc_label_site + 2), (long) pc_l4));
+
+ duk__patch_jump(comp_ctx, pc_jumpto_l2, pc_l2);
+ duk__patch_jump(comp_ctx, pc_jumpto_l3, pc_l3);
+ duk__patch_jump(comp_ctx, pc_jumpto_l4, pc_l4);
+ duk__patch_jump(comp_ctx, pc_jumpto_l5, pc_l5);
+ duk__patch_jump(comp_ctx, pc_label_site + 1, pc_l5); /* break jump */
+ duk__patch_jump(comp_ctx, pc_label_site + 2, pc_l4); /* continue jump */
+ }
+ goto finished;
+
+ finished:
+ DUK_DDD(DUK_DDDPRINT("end parsing a for/for-in statement"));
+ return;
+
+ syntax_error:
+ DUK_ERROR_SYNTAX(thr, DUK_STR_INVALID_FOR);
+}
+
+DUK_LOCAL void duk__parse_switch_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_int_t pc_label_site) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_reg_t temp_at_loop;
+ duk_regconst_t rc_switch; /* reg/const for switch value */
+ duk_regconst_t rc_case; /* reg/const for case value */
+ duk_reg_t reg_temp; /* general temp register */
+ duk_int_t pc_prevcase = -1;
+ duk_int_t pc_prevstmt = -1;
+ duk_int_t pc_default = -1; /* -1 == not set, -2 == pending (next statement list) */
+
+ /* Note: negative pc values are ignored when patching jumps, so no explicit checks needed */
+
+ /*
+ * Switch is pretty complicated because of several conflicting concerns:
+ *
+ * - Want to generate code without an intermediate representation,
+ * i.e., in one go
+ *
+ * - Case selectors are expressions, not values, and may thus e.g. throw
+ * exceptions (which causes evaluation order concerns)
+ *
+ * - Evaluation semantics of case selectors and default clause need to be
+ * carefully implemented to provide correct behavior even with case value
+ * side effects
+ *
+ * - Fall through case and default clauses; avoiding dead JUMPs if case
+ * ends with an unconditional jump (a break or a continue)
+ *
+ * - The same case value may occur multiple times, but evaluation rules
+ * only process the first match before switching to a "propagation" mode
+ * where case values are no longer evaluated
+ *
+ * See E5 Section 12.11. Also see doc/compiler.rst for compilation
+ * discussion.
+ */
+
+ duk__advance(comp_ctx);
+ duk__advance_expect(comp_ctx, DUK_TOK_LPAREN);
+ rc_switch = duk__exprtop_toregconst(comp_ctx, res, DUK__BP_FOR_EXPR /*rbp_flags*/);
+ duk__advance_expect(comp_ctx, DUK_TOK_RPAREN);
+ duk__advance_expect(comp_ctx, DUK_TOK_LCURLY);
+
+ DUK_DDD(DUK_DDDPRINT("switch value in register %ld", (long) rc_switch));
+
+ temp_at_loop = DUK__GETTEMP(comp_ctx);
+
+ for (;;) {
+ duk_int_t num_stmts;
+ duk_small_int_t tok;
+
+ /* sufficient for keeping temp reg numbers in check */
+ DUK__SETTEMP(comp_ctx, temp_at_loop);
+
+ if (comp_ctx->curr_token.t == DUK_TOK_RCURLY) {
+ break;
+ }
+
+ /*
+ * Parse a case or default clause.
+ */
+
+ if (comp_ctx->curr_token.t == DUK_TOK_CASE) {
+ /*
+ * Case clause.
+ *
+ * Note: cannot use reg_case as a temp register (for SEQ target)
+ * because it may be a constant.
+ */
+
+ duk__patch_jump_here(comp_ctx, pc_prevcase); /* chain jumps for case
+ * evaluation and checking
+ */
+
+ duk__advance(comp_ctx);
+ rc_case = duk__exprtop_toregconst(comp_ctx, res, DUK__BP_FOR_EXPR /*rbp_flags*/);
+ duk__advance_expect(comp_ctx, DUK_TOK_COLON);
+
+ reg_temp = DUK__ALLOCTEMP(comp_ctx);
+ duk__emit_a_b_c(comp_ctx,
+ DUK_OP_SEQ,
+ (duk_regconst_t) reg_temp,
+ rc_switch,
+ rc_case);
+ duk__emit_if_true_skip(comp_ctx, (duk_regconst_t) reg_temp);
+
+ /* jump to next case clause */
+ pc_prevcase = duk__emit_jump_empty(comp_ctx); /* no match, next case */
+
+ /* statements go here (if any) on next loop */
+ } else if (comp_ctx->curr_token.t == DUK_TOK_DEFAULT) {
+ /*
+ * Default clause.
+ */
+
+ if (pc_default >= 0) {
+ goto syntax_error;
+ }
+ duk__advance(comp_ctx);
+ duk__advance_expect(comp_ctx, DUK_TOK_COLON);
+
+ /* Fix for https://github.com/svaarala/duktape/issues/155:
+ * If 'default' is first clause (detected by pc_prevcase < 0)
+ * we need to ensure we stay in the matching chain.
+ */
+ if (pc_prevcase < 0) {
+ DUK_DD(DUK_DDPRINT("default clause is first, emit prevcase jump"));
+ pc_prevcase = duk__emit_jump_empty(comp_ctx);
+ }
+
+ /* default clause matches next statement list (if any) */
+ pc_default = -2;
+ } else {
+ /* Code is not accepted before the first case/default clause */
+ goto syntax_error;
+ }
+
+ /*
+ * Parse code after the clause. Possible terminators are
+ * 'case', 'default', and '}'.
+ *
+ * Note that there may be no code at all, not even an empty statement,
+ * between case clauses. This must be handled just like an empty statement
+ * (omitting seemingly pointless JUMPs), to avoid situations like
+ * test-bug-case-fallthrough.js.
+ */
+
+ num_stmts = 0;
+ if (pc_default == -2) {
+ pc_default = duk__get_current_pc(comp_ctx);
+ }
+
+ /* Note: this is correct even for default clause statements:
+ * they participate in 'fall-through' behavior even if the
+ * default clause is in the middle.
+ */
+ duk__patch_jump_here(comp_ctx, pc_prevstmt); /* chain jumps for 'fall-through'
+ * after a case matches.
+ */
+
+ for (;;) {
+ tok = comp_ctx->curr_token.t;
+ if (tok == DUK_TOK_CASE || tok == DUK_TOK_DEFAULT ||
+ tok == DUK_TOK_RCURLY) {
+ break;
+ }
+ num_stmts++;
+ duk__parse_stmt(comp_ctx, res, 0 /*allow_source_elem*/);
+ }
+
+ /* fall-through jump to next code of next case (backpatched) */
+ pc_prevstmt = duk__emit_jump_empty(comp_ctx);
+
+ /* XXX: would be nice to omit this jump when the jump is not
+ * reachable, at least in the obvious cases (such as the case
+ * ending with a 'break'.
+ *
+ * Perhaps duk__parse_stmt() could provide some info on whether
+ * the statement is a "dead end"?
+ *
+ * If implemented, just set pc_prevstmt to -1 when not needed.
+ */
+ }
+
+ DUK_ASSERT(comp_ctx->curr_token.t == DUK_TOK_RCURLY);
+ duk__advance(comp_ctx);
+
+ /* default case control flow patchup; note that if pc_prevcase < 0
+ * (i.e. no case clauses), control enters default case automatically.
+ */
+ if (pc_default >= 0) {
+ /* default case exists: go there if no case matches */
+ duk__patch_jump(comp_ctx, pc_prevcase, pc_default);
+ } else {
+ /* default case does not exist, or no statements present
+ * after default case: finish case evaluation
+ */
+ duk__patch_jump_here(comp_ctx, pc_prevcase);
+ }
+
+ /* fall-through control flow patchup; note that pc_prevstmt may be
+ * < 0 (i.e. no case clauses), in which case this is a no-op.
+ */
+ duk__patch_jump_here(comp_ctx, pc_prevstmt);
+
+ /* continue jump not patched, an INVALID opcode remains there */
+ duk__patch_jump_here(comp_ctx, pc_label_site + 1); /* break jump */
+
+ /* Note: 'fast' breaks will jump to pc_label_site + 1, which will
+ * then jump here. The double jump will be eliminated by a
+ * peephole pass, resulting in an optimal jump here. The label
+ * site jumps will remain in bytecode and will waste code size.
+ */
+
+ return;
+
+ syntax_error:
+ DUK_ERROR_SYNTAX(thr, DUK_STR_INVALID_SWITCH);
+}
+
+DUK_LOCAL void duk__parse_if_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res) {
+ duk_reg_t temp_reset;
+ duk_regconst_t rc_cond;
+ duk_int_t pc_jump_false;
+
+ DUK_DDD(DUK_DDDPRINT("begin parsing if statement"));
+
+ temp_reset = DUK__GETTEMP(comp_ctx);
+
+ duk__advance(comp_ctx); /* eat 'if' */
+ duk__advance_expect(comp_ctx, DUK_TOK_LPAREN);
+
+ rc_cond = duk__exprtop_toregconst(comp_ctx, res, DUK__BP_FOR_EXPR /*rbp_flags*/);
+ duk__emit_if_true_skip(comp_ctx, rc_cond);
+ pc_jump_false = duk__emit_jump_empty(comp_ctx); /* jump to end or else part */
+ DUK__SETTEMP(comp_ctx, temp_reset);
+
+ duk__advance_expect(comp_ctx, DUK_TOK_RPAREN);
+
+ duk__parse_stmt(comp_ctx, res, 0 /*allow_source_elem*/);
+
+ /* The 'else' ambiguity is resolved by 'else' binding to the innermost
+ * construct, so greedy matching is correct here.
+ */
+
+ if (comp_ctx->curr_token.t == DUK_TOK_ELSE) {
+ duk_int_t pc_jump_end;
+
+ DUK_DDD(DUK_DDDPRINT("if has else part"));
+
+ duk__advance(comp_ctx);
+
+ pc_jump_end = duk__emit_jump_empty(comp_ctx); /* jump from true part to end */
+ duk__patch_jump_here(comp_ctx, pc_jump_false);
+
+ duk__parse_stmt(comp_ctx, res, 0 /*allow_source_elem*/);
+
+ duk__patch_jump_here(comp_ctx, pc_jump_end);
+ } else {
+ DUK_DDD(DUK_DDDPRINT("if does not have else part"));
+
+ duk__patch_jump_here(comp_ctx, pc_jump_false);
+ }
+
+ DUK_DDD(DUK_DDDPRINT("end parsing if statement"));
+}
+
+DUK_LOCAL void duk__parse_do_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_int_t pc_label_site) {
+ duk_regconst_t rc_cond;
+ duk_int_t pc_start;
+
+ DUK_DDD(DUK_DDDPRINT("begin parsing do statement"));
+
+ duk__advance(comp_ctx); /* eat 'do' */
+
+ pc_start = duk__get_current_pc(comp_ctx);
+ duk__parse_stmt(comp_ctx, res, 0 /*allow_source_elem*/);
+ duk__patch_jump_here(comp_ctx, pc_label_site + 2); /* continue jump */
+
+ duk__advance_expect(comp_ctx, DUK_TOK_WHILE);
+ duk__advance_expect(comp_ctx, DUK_TOK_LPAREN);
+
+ rc_cond = duk__exprtop_toregconst(comp_ctx, res, DUK__BP_FOR_EXPR /*rbp_flags*/);
+ duk__emit_if_false_skip(comp_ctx, rc_cond);
+ duk__emit_jump(comp_ctx, pc_start);
+ /* no need to reset temps, as we're finished emitting code */
+
+ duk__advance_expect(comp_ctx, DUK_TOK_RPAREN);
+
+ duk__patch_jump_here(comp_ctx, pc_label_site + 1); /* break jump */
+
+ DUK_DDD(DUK_DDDPRINT("end parsing do statement"));
+}
+
+DUK_LOCAL void duk__parse_while_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_int_t pc_label_site) {
+ duk_reg_t temp_reset;
+ duk_regconst_t rc_cond;
+ duk_int_t pc_start;
+ duk_int_t pc_jump_false;
+
+ DUK_DDD(DUK_DDDPRINT("begin parsing while statement"));
+
+ temp_reset = DUK__GETTEMP(comp_ctx);
+
+ duk__advance(comp_ctx); /* eat 'while' */
+
+ duk__advance_expect(comp_ctx, DUK_TOK_LPAREN);
+
+ pc_start = duk__get_current_pc(comp_ctx);
+ duk__patch_jump_here(comp_ctx, pc_label_site + 2); /* continue jump */
+
+ rc_cond = duk__exprtop_toregconst(comp_ctx, res, DUK__BP_FOR_EXPR /*rbp_flags*/);
+ duk__emit_if_true_skip(comp_ctx, rc_cond);
+ pc_jump_false = duk__emit_jump_empty(comp_ctx);
+ DUK__SETTEMP(comp_ctx, temp_reset);
+
+ duk__advance_expect(comp_ctx, DUK_TOK_RPAREN);
+
+ duk__parse_stmt(comp_ctx, res, 0 /*allow_source_elem*/);
+ duk__emit_jump(comp_ctx, pc_start);
+
+ duk__patch_jump_here(comp_ctx, pc_jump_false);
+ duk__patch_jump_here(comp_ctx, pc_label_site + 1); /* break jump */
+
+ DUK_DDD(DUK_DDDPRINT("end parsing while statement"));
+}
+
+DUK_LOCAL void duk__parse_break_or_continue_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_bool_t is_break = (comp_ctx->curr_token.t == DUK_TOK_BREAK);
+ duk_int_t label_id;
+ duk_int_t label_catch_depth;
+ duk_int_t label_pc; /* points to LABEL; pc+1 = jump site for break; pc+2 = jump site for continue */
+ duk_bool_t label_is_closest;
+
+ DUK_UNREF(res);
+
+ duk__advance(comp_ctx); /* eat 'break' or 'continue' */
+
+ if (comp_ctx->curr_token.t == DUK_TOK_SEMICOLON || /* explicit semi follows */
+ comp_ctx->curr_token.lineterm || /* automatic semi will be inserted */
+ comp_ctx->curr_token.allow_auto_semi) { /* automatic semi will be inserted */
+ /* break/continue without label */
+
+ duk__lookup_active_label(comp_ctx, DUK_HTHREAD_STRING_EMPTY_STRING(thr), is_break, &label_id, &label_catch_depth, &label_pc, &label_is_closest);
+ } else if (comp_ctx->curr_token.t == DUK_TOK_IDENTIFIER) {
+ /* break/continue with label (label cannot be a reserved word, production is 'Identifier' */
+ DUK_ASSERT(comp_ctx->curr_token.str1 != NULL);
+ duk__lookup_active_label(comp_ctx, comp_ctx->curr_token.str1, is_break, &label_id, &label_catch_depth, &label_pc, &label_is_closest);
+ duk__advance(comp_ctx);
+ } else {
+ DUK_ERROR_SYNTAX(thr, DUK_STR_INVALID_BREAK_CONT_LABEL);
+ }
+
+ /* Use a fast break/continue when possible. A fast break/continue is
+ * just a jump to the LABEL break/continue jump slot, which then jumps
+ * to an appropriate place (for break, going through ENDLABEL correctly).
+ * The peephole optimizer will optimize the jump to a direct one.
+ */
+
+ if (label_catch_depth == comp_ctx->curr_func.catch_depth &&
+ label_is_closest) {
+ DUK_DDD(DUK_DDDPRINT("break/continue: is_break=%ld, label_id=%ld, label_is_closest=%ld, "
+ "label_catch_depth=%ld, catch_depth=%ld "
+ "-> use fast variant (direct jump)",
+ (long) is_break, (long) label_id, (long) label_is_closest,
+ (long) label_catch_depth, (long) comp_ctx->curr_func.catch_depth));
+
+ duk__emit_jump(comp_ctx, label_pc + (is_break ? 1 : 2));
+ } else {
+ DUK_DDD(DUK_DDDPRINT("break/continue: is_break=%ld, label_id=%ld, label_is_closest=%ld, "
+ "label_catch_depth=%ld, catch_depth=%ld "
+ "-> use slow variant (longjmp)",
+ (long) is_break, (long) label_id, (long) label_is_closest,
+ (long) label_catch_depth, (long) comp_ctx->curr_func.catch_depth));
+
+ duk__emit_extraop_bc(comp_ctx,
+ is_break ? DUK_EXTRAOP_BREAK : DUK_EXTRAOP_CONTINUE,
+ (duk_regconst_t) label_id);
+ }
+}
+
+DUK_LOCAL void duk__parse_return_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_regconst_t rc_val;
+ duk_small_uint_t ret_flags;
+
+ duk__advance(comp_ctx); /* eat 'return' */
+
+ /* A 'return' statement is only allowed inside an actual function body,
+ * not as part of eval or global code.
+ */
+ if (!comp_ctx->curr_func.is_function) {
+ DUK_ERROR_SYNTAX(thr, DUK_STR_INVALID_RETURN);
+ }
+
+ ret_flags = 0;
+
+ if (comp_ctx->curr_token.t == DUK_TOK_SEMICOLON || /* explicit semi follows */
+ comp_ctx->curr_token.lineterm || /* automatic semi will be inserted */
+ comp_ctx->curr_token.allow_auto_semi) { /* automatic semi will be inserted */
+ DUK_DDD(DUK_DDDPRINT("empty return value -> undefined"));
+ rc_val = 0;
+ } else {
+ duk_int_t pc_before_expr;
+ duk_int_t pc_after_expr;
+
+ DUK_DDD(DUK_DDDPRINT("return with a value"));
+
+ DUK_UNREF(pc_before_expr);
+ DUK_UNREF(pc_after_expr);
+
+ pc_before_expr = duk__get_current_pc(comp_ctx);
+ rc_val = duk__exprtop_toregconst(comp_ctx, res, DUK__BP_FOR_EXPR /*rbp_flags*/);
+ pc_after_expr = duk__get_current_pc(comp_ctx);
+
+ /* Tail call check: if last opcode emitted was CALL(I), and
+ * the context allows it, change the CALL(I) to a tail call.
+ * This doesn't guarantee that a tail call will be allowed at
+ * runtime, so the RETURN must still be emitted. (Duktape
+ * 0.10.0 avoided this and simulated a RETURN if a tail call
+ * couldn't be used at runtime; but this didn't work
+ * correctly with a thread yield/resume, see
+ * test-bug-tailcall-thread-yield-resume.js for discussion.)
+ *
+ * In addition to the last opcode being CALL, we also need to
+ * be sure that 'rc_val' is the result register of the CALL(I).
+ * For instance, for the expression 'return 0, (function ()
+ * { return 1; }), 2' the last opcode emitted is CALL (no
+ * bytecode is emitted for '2') but 'rc_val' indicates
+ * constant '2'. Similarly if '2' is replaced by a register
+ * bound variable, no opcodes are emitted but tail call would
+ * be incorrect.
+ *
+ * This is tricky and easy to get wrong. It would be best to
+ * track enough expression metadata to check that 'rc_val' came
+ * from that last CALL instruction. We don't have that metadata
+ * now, so we check that 'rc_val' is a temporary register result
+ * (not a constant or a register bound variable). There should
+ * be no way currently for 'rc_val' to be a temporary for an
+ * expression following the CALL instruction without emitting
+ * some opcodes following the CALL. This proxy check is used
+ * below.
+ *
+ * See: test-bug-comma-expr-gh131.js.
+ *
+ * The non-standard 'caller' property disables tail calls
+ * because they pose some special cases which haven't been
+ * fixed yet.
+ */
+
+#if defined(DUK_USE_TAILCALL)
+ if (comp_ctx->curr_func.catch_depth == 0 && /* no catchers */
+ pc_after_expr > pc_before_expr) { /* at least one opcode emitted */
+ duk_compiler_instr *instr;
+ duk_small_uint_t op;
+
+ instr = duk__get_instr_ptr(comp_ctx, pc_after_expr - 1);
+ DUK_ASSERT(instr != NULL);
+
+ op = (duk_small_uint_t) DUK_DEC_OP(instr->ins);
+ if ((op == DUK_OP_CALL || op == DUK_OP_CALLI) &&
+ DUK__ISTEMP(comp_ctx, rc_val) /* see above */) {
+ DUK_DDD(DUK_DDDPRINT("return statement detected a tail call opportunity: "
+ "catch depth is 0, duk__exprtop() emitted >= 1 instructions, "
+ "and last instruction is a CALL "
+ "-> set TAILCALL flag"));
+ /* Just flip the single bit. */
+ instr->ins |= DUK_ENC_OP_A_B_C(0, DUK_BC_CALL_FLAG_TAILCALL, 0, 0);
+ }
+ }
+#endif /* DUK_USE_TAILCALL */
+
+ ret_flags = DUK_BC_RETURN_FLAG_HAVE_RETVAL;
+ }
+
+ duk__emit_a_b(comp_ctx,
+ DUK_OP_RETURN | DUK__EMIT_FLAG_NO_SHUFFLE_A,
+ (duk_regconst_t) ret_flags /*flags*/,
+ rc_val /*reg*/);
+}
+
+DUK_LOCAL void duk__parse_throw_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res) {
+ duk_reg_t reg_val;
+
+ duk__advance(comp_ctx); /* eat 'throw' */
+
+ /* Unlike break/continue, throw statement does not allow an empty value. */
+
+ if (comp_ctx->curr_token.lineterm) {
+ DUK_ERROR_SYNTAX(comp_ctx->thr, DUK_STR_INVALID_THROW);
+ }
+
+ reg_val = duk__exprtop_toreg(comp_ctx, res, DUK__BP_FOR_EXPR /*rbp_flags*/);
+ duk__emit_extraop_bc(comp_ctx,
+ DUK_EXTRAOP_THROW,
+ (duk_regconst_t) reg_val);
+}
+
+DUK_LOCAL void duk__parse_try_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_reg_t reg_catch; /* reg_catch+0 and reg_catch+1 are reserved for TRYCATCH */
+ duk_regconst_t rc_varname = 0;
+ duk_small_uint_t trycatch_flags = 0;
+ duk_int_t pc_ldconst = -1;
+ duk_int_t pc_trycatch = -1;
+ duk_int_t pc_catch = -1;
+ duk_int_t pc_finally = -1;
+
+ DUK_UNREF(res);
+
+ /*
+ * See the following documentation for discussion:
+ *
+ * doc/execution.rst: control flow details
+ *
+ * Try, catch, and finally "parts" are Blocks, not Statements, so
+ * they must always be delimited by curly braces. This is unlike e.g.
+ * the if statement, which accepts any Statement. This eliminates any
+ * questions of matching parts of nested try statements. The Block
+ * parsing is implemented inline here (instead of calling out).
+ *
+ * Finally part has a 'let scoped' variable, which requires a few kinks
+ * here.
+ */
+
+ comp_ctx->curr_func.catch_depth++;
+
+ duk__advance(comp_ctx); /* eat 'try' */
+
+ reg_catch = DUK__ALLOCTEMPS(comp_ctx, 2);
+
+ /* The target for this LDCONST may need output shuffling, but we assume
+ * that 'pc_ldconst' will be the LDCONST that we can patch later. This
+ * should be the case because there's no input shuffling. (If there's
+ * no catch clause, this LDCONST will be replaced with a NOP.)
+ */
+ pc_ldconst = duk__get_current_pc(comp_ctx);
+ duk__emit_a_bc(comp_ctx, DUK_OP_LDCONST, reg_catch, 0 /*patched later*/);
+
+ pc_trycatch = duk__get_current_pc(comp_ctx);
+ duk__emit_invalid(comp_ctx); /* TRYCATCH, cannot emit now (not enough info) */
+ duk__emit_invalid(comp_ctx); /* jump for 'catch' case */
+ duk__emit_invalid(comp_ctx); /* jump for 'finally' case or end (if no finally) */
+
+ /* try part */
+ duk__advance_expect(comp_ctx, DUK_TOK_LCURLY);
+ duk__parse_stmts(comp_ctx, 0 /*allow_source_elem*/, 0 /*expect_eof*/);
+ /* the DUK_TOK_RCURLY is eaten by duk__parse_stmts() */
+ duk__emit_extraop_only(comp_ctx,
+ DUK_EXTRAOP_ENDTRY);
+
+ if (comp_ctx->curr_token.t == DUK_TOK_CATCH) {
+ /*
+ * The catch variable must be updated to reflect the new allocated
+ * register for the duration of the catch clause. We need to store
+ * and restore the original value for the varmap entry (if any).
+ */
+
+ /*
+ * Note: currently register bindings must be fixed for the entire
+ * function. So, even though the catch variable is in a register
+ * we know, we must use an explicit environment record and slow path
+ * accesses to read/write the catch binding to make closures created
+ * within the catch clause work correctly. This restriction should
+ * be fixable (at least in common cases) later.
+ *
+ * See: test-bug-catch-binding-2.js.
+ *
+ * XXX: improve to get fast path access to most catch clauses.
+ */
+
+ duk_hstring *h_var;
+ duk_int_t varmap_value; /* for storing/restoring the varmap binding for catch variable */
+
+ DUK_DDD(DUK_DDDPRINT("stack top at start of catch clause: %ld", (long) duk_get_top(ctx)));
+
+ trycatch_flags |= DUK_BC_TRYCATCH_FLAG_HAVE_CATCH;
+
+ pc_catch = duk__get_current_pc(comp_ctx);
+
+ duk__advance(comp_ctx);
+ duk__advance_expect(comp_ctx, DUK_TOK_LPAREN);
+
+ if (comp_ctx->curr_token.t != DUK_TOK_IDENTIFIER) {
+ /* Identifier, i.e. don't allow reserved words */
+ goto syntax_error;
+ }
+ h_var = comp_ctx->curr_token.str1;
+ DUK_ASSERT(h_var != NULL);
+
+ duk_push_hstring(ctx, h_var); /* keep in on valstack, use borrowed ref below */
+
+ if (comp_ctx->curr_func.is_strict &&
+ ((h_var == DUK_HTHREAD_STRING_EVAL(thr)) ||
+ (h_var == DUK_HTHREAD_STRING_LC_ARGUMENTS(thr)))) {
+ DUK_DDD(DUK_DDDPRINT("catch identifier 'eval' or 'arguments' in strict mode -> SyntaxError"));
+ goto syntax_error;
+ }
+
+ duk_dup_top(ctx);
+ rc_varname = duk__getconst(comp_ctx);
+ DUK_DDD(DUK_DDDPRINT("catch clause, rc_varname=0x%08lx (%ld)",
+ (unsigned long) rc_varname, (long) rc_varname));
+
+ duk__advance(comp_ctx);
+ duk__advance_expect(comp_ctx, DUK_TOK_RPAREN);
+
+ duk__advance_expect(comp_ctx, DUK_TOK_LCURLY);
+
+ DUK_DDD(DUK_DDDPRINT("varmap before modifying for catch clause: %!iT",
+ (duk_tval *) duk_get_tval(ctx, comp_ctx->curr_func.varmap_idx)));
+
+ duk_dup_top(ctx);
+ duk_get_prop(ctx, comp_ctx->curr_func.varmap_idx);
+ if (duk_is_undefined(ctx, -1)) {
+ varmap_value = -2;
+ } else if (duk_is_null(ctx, -1)) {
+ varmap_value = -1;
+ } else {
+ DUK_ASSERT(duk_is_number(ctx, -1));
+ varmap_value = duk_get_int(ctx, -1);
+ DUK_ASSERT(varmap_value >= 0);
+ }
+ duk_pop(ctx);
+
+#if 0
+ /* It'd be nice to do something like this - but it doesn't
+ * work for closures created inside the catch clause.
+ */
+ duk_dup_top(ctx);
+ duk_push_int(ctx, (duk_int_t) (reg_catch + 0));
+ duk_put_prop(ctx, comp_ctx->curr_func.varmap_idx);
+#endif
+ duk_dup_top(ctx);
+ duk_push_null(ctx);
+ duk_put_prop(ctx, comp_ctx->curr_func.varmap_idx);
+
+ duk__emit_a_bc(comp_ctx,
+ DUK_OP_PUTVAR | DUK__EMIT_FLAG_A_IS_SOURCE,
+ (duk_regconst_t) (reg_catch + 0) /*value*/,
+ rc_varname /*varname*/);
+
+ DUK_DDD(DUK_DDDPRINT("varmap before parsing catch clause: %!iT",
+ (duk_tval *) duk_get_tval(ctx, comp_ctx->curr_func.varmap_idx)));
+
+ duk__parse_stmts(comp_ctx, 0 /*allow_source_elem*/, 0 /*expect_eof*/);
+ /* the DUK_TOK_RCURLY is eaten by duk__parse_stmts() */
+
+ if (varmap_value == -2) {
+ /* not present */
+ duk_del_prop(ctx, comp_ctx->curr_func.varmap_idx);
+ } else {
+ if (varmap_value == -1) {
+ duk_push_null(ctx);
+ } else {
+ DUK_ASSERT(varmap_value >= 0);
+ duk_push_int(ctx, varmap_value);
+ }
+ duk_put_prop(ctx, comp_ctx->curr_func.varmap_idx);
+ }
+ /* varname is popped by above code */
+
+ DUK_DDD(DUK_DDDPRINT("varmap after restore catch clause: %!iT",
+ (duk_tval *) duk_get_tval(ctx, comp_ctx->curr_func.varmap_idx)));
+
+ duk__emit_extraop_only(comp_ctx,
+ DUK_EXTRAOP_ENDCATCH);
+
+ /*
+ * XXX: for now, indicate that an expensive catch binding
+ * declarative environment is always needed. If we don't
+ * need it, we don't need the const_varname either.
+ */
+
+ trycatch_flags |= DUK_BC_TRYCATCH_FLAG_CATCH_BINDING;
+
+ DUK_DDD(DUK_DDDPRINT("stack top at end of catch clause: %ld", (long) duk_get_top(ctx)));
+ }
+
+ if (comp_ctx->curr_token.t == DUK_TOK_FINALLY) {
+ trycatch_flags |= DUK_BC_TRYCATCH_FLAG_HAVE_FINALLY;
+
+ pc_finally = duk__get_current_pc(comp_ctx);
+
+ duk__advance(comp_ctx);
+
+ duk__advance_expect(comp_ctx, DUK_TOK_LCURLY);
+ duk__parse_stmts(comp_ctx, 0 /*allow_source_elem*/, 0 /*expect_eof*/);
+ /* the DUK_TOK_RCURLY is eaten by duk__parse_stmts() */
+ duk__emit_extraop_b(comp_ctx,
+ DUK_EXTRAOP_ENDFIN,
+ reg_catch); /* rethrow */
+ }
+
+ if (!(trycatch_flags & DUK_BC_TRYCATCH_FLAG_HAVE_CATCH) &&
+ !(trycatch_flags & DUK_BC_TRYCATCH_FLAG_HAVE_FINALLY)) {
+ /* must have catch and/or finally */
+ goto syntax_error;
+ }
+
+ /* If there's no catch block, rc_varname will be 0 and duk__patch_trycatch()
+ * will replace the LDCONST with a NOP. For any actual constant (including
+ * constant 0) the DUK__CONST_MARKER flag will be set in rc_varname.
+ */
+
+ duk__patch_trycatch(comp_ctx,
+ pc_ldconst,
+ pc_trycatch,
+ reg_catch,
+ rc_varname,
+ trycatch_flags);
+
+ if (trycatch_flags & DUK_BC_TRYCATCH_FLAG_HAVE_CATCH) {
+ DUK_ASSERT(pc_catch >= 0);
+ duk__patch_jump(comp_ctx, pc_trycatch + 1, pc_catch);
+ }
+
+ if (trycatch_flags & DUK_BC_TRYCATCH_FLAG_HAVE_FINALLY) {
+ DUK_ASSERT(pc_finally >= 0);
+ duk__patch_jump(comp_ctx, pc_trycatch + 2, pc_finally);
+ } else {
+ /* without finally, the second jump slot is used to jump to end of stmt */
+ duk__patch_jump_here(comp_ctx, pc_trycatch + 2);
+ }
+
+ comp_ctx->curr_func.catch_depth--;
+ return;
+
+ syntax_error:
+ DUK_ERROR_SYNTAX(thr, DUK_STR_INVALID_TRY);
+}
+
+DUK_LOCAL void duk__parse_with_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res) {
+ duk_int_t pc_trycatch;
+ duk_int_t pc_finished;
+ duk_reg_t reg_catch;
+ duk_small_uint_t trycatch_flags;
+
+ if (comp_ctx->curr_func.is_strict) {
+ DUK_ERROR_SYNTAX(comp_ctx->thr, DUK_STR_WITH_IN_STRICT_MODE);
+ }
+
+ comp_ctx->curr_func.catch_depth++;
+
+ duk__advance(comp_ctx); /* eat 'with' */
+
+ reg_catch = DUK__ALLOCTEMPS(comp_ctx, 2);
+
+ duk__advance_expect(comp_ctx, DUK_TOK_LPAREN);
+ duk__exprtop_toforcedreg(comp_ctx, res, DUK__BP_FOR_EXPR /*rbp_flags*/, reg_catch);
+ duk__advance_expect(comp_ctx, DUK_TOK_RPAREN);
+
+ pc_trycatch = duk__get_current_pc(comp_ctx);
+ trycatch_flags = DUK_BC_TRYCATCH_FLAG_WITH_BINDING;
+ duk__emit_a_bc(comp_ctx,
+ DUK_OP_TRYCATCH | DUK__EMIT_FLAG_NO_SHUFFLE_A,
+ (duk_regconst_t) trycatch_flags /*a*/,
+ (duk_regconst_t) reg_catch /*bc*/);
+ duk__emit_invalid(comp_ctx); /* catch jump */
+ duk__emit_invalid(comp_ctx); /* finished jump */
+
+ duk__parse_stmt(comp_ctx, res, 0 /*allow_source_elem*/);
+ duk__emit_extraop_only(comp_ctx,
+ DUK_EXTRAOP_ENDTRY);
+
+ pc_finished = duk__get_current_pc(comp_ctx);
+
+ duk__patch_jump(comp_ctx, pc_trycatch + 2, pc_finished);
+
+ comp_ctx->curr_func.catch_depth--;
+}
+
+DUK_LOCAL duk_int_t duk__stmt_label_site(duk_compiler_ctx *comp_ctx, duk_int_t label_id) {
+ /* if a site already exists, nop: max one label site per statement */
+ if (label_id >= 0) {
+ return label_id;
+ }
+
+ label_id = comp_ctx->curr_func.label_next++;
+ DUK_DDD(DUK_DDDPRINT("allocated new label id for label site: %ld", (long) label_id));
+
+ duk__emit_extraop_bc(comp_ctx,
+ DUK_EXTRAOP_LABEL,
+ (duk_regconst_t) label_id);
+ duk__emit_invalid(comp_ctx);
+ duk__emit_invalid(comp_ctx);
+
+ return label_id;
+}
+
+/* Parse a single statement.
+ *
+ * Creates a label site (with an empty label) automatically for iteration
+ * statements. Also "peels off" any label statements for explicit labels.
+ */
+DUK_LOCAL void duk__parse_stmt(duk_compiler_ctx *comp_ctx, duk_ivalue *res, duk_bool_t allow_source_elem) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_bool_t dir_prol_at_entry; /* directive prologue status at entry */
+ duk_reg_t temp_at_entry;
+ duk_uarridx_t labels_len_at_entry;
+ duk_int_t pc_at_entry; /* assumed to also be PC of "LABEL" */
+ duk_int_t stmt_id;
+ duk_small_uint_t stmt_flags = 0;
+ duk_int_t label_id = -1;
+ duk_small_uint_t tok;
+
+ DUK__RECURSION_INCREASE(comp_ctx, thr);
+
+ temp_at_entry = DUK__GETTEMP(comp_ctx);
+ pc_at_entry = duk__get_current_pc(comp_ctx);
+ labels_len_at_entry = (duk_uarridx_t) duk_get_length(ctx, comp_ctx->curr_func.labelnames_idx);
+ stmt_id = comp_ctx->curr_func.stmt_next++;
+ dir_prol_at_entry = comp_ctx->curr_func.in_directive_prologue;
+
+ DUK_UNREF(stmt_id);
+
+ DUK_DDD(DUK_DDDPRINT("parsing a statement, stmt_id=%ld, temp_at_entry=%ld, labels_len_at_entry=%ld, "
+ "is_strict=%ld, in_directive_prologue=%ld, catch_depth=%ld",
+ (long) stmt_id, (long) temp_at_entry, (long) labels_len_at_entry,
+ (long) comp_ctx->curr_func.is_strict, (long) comp_ctx->curr_func.in_directive_prologue,
+ (long) comp_ctx->curr_func.catch_depth));
+
+ /* The directive prologue flag is cleared by default so that it is
+ * unset for any recursive statement parsing. It is only "revived"
+ * if a directive is detected. (We could also make directives only
+ * allowed if 'allow_source_elem' was true.)
+ */
+ comp_ctx->curr_func.in_directive_prologue = 0;
+
+ retry_parse:
+
+ DUK_DDD(DUK_DDDPRINT("try stmt parse, stmt_id=%ld, label_id=%ld, allow_source_elem=%ld, catch_depth=%ld",
+ (long) stmt_id, (long) label_id, (long) allow_source_elem,
+ (long) comp_ctx->curr_func.catch_depth));
+
+ /*
+ * Detect iteration statements; if encountered, establish an
+ * empty label.
+ */
+
+ tok = comp_ctx->curr_token.t;
+ if (tok == DUK_TOK_FOR || tok == DUK_TOK_DO || tok == DUK_TOK_WHILE ||
+ tok == DUK_TOK_SWITCH) {
+ DUK_DDD(DUK_DDDPRINT("iteration/switch statement -> add empty label"));
+
+ label_id = duk__stmt_label_site(comp_ctx, label_id);
+ duk__add_label(comp_ctx,
+ DUK_HTHREAD_STRING_EMPTY_STRING(thr),
+ pc_at_entry /*pc_label*/,
+ label_id);
+ }
+
+ /*
+ * Main switch for statement / source element type.
+ */
+
+ switch (comp_ctx->curr_token.t) {
+ case DUK_TOK_FUNCTION: {
+ /*
+ * Function declaration, function expression, or (non-standard)
+ * function statement.
+ *
+ * The E5 specification only allows function declarations at
+ * the top level (in "source elements"). An ExpressionStatement
+ * is explicitly not allowed to begin with a "function" keyword
+ * (E5 Section 12.4). Hence any non-error semantics for such
+ * non-top-level statements are non-standard. Duktape semantics
+ * for function statements are modelled after V8, see
+ * test-dev-func-decl-outside-top.js.
+ */
+
+#if defined(DUK_USE_NONSTD_FUNC_STMT)
+ /* Lenient: allow function declarations outside top level in
+ * non-strict mode but reject them in strict mode.
+ */
+ if (allow_source_elem || !comp_ctx->curr_func.is_strict)
+#else /* DUK_USE_NONSTD_FUNC_STMT */
+ /* Strict: never allow function declarations outside top level. */
+ if (allow_source_elem)
+#endif /* DUK_USE_NONSTD_FUNC_STMT */
+ {
+ /* FunctionDeclaration: not strictly a statement but handled as such.
+ *
+ * O(depth^2) parse count for inner functions is handled by recording a
+ * lexer offset on the first compilation pass, so that the function can
+ * be efficiently skipped on the second pass. This is encapsulated into
+ * duk__parse_func_like_fnum().
+ */
+
+ duk_int_t fnum;
+
+ DUK_DDD(DUK_DDDPRINT("function declaration statement"));
+
+ duk__advance(comp_ctx); /* eat 'function' */
+ fnum = duk__parse_func_like_fnum(comp_ctx, 1 /*is_decl*/, 0 /*is_setget*/);
+
+ if (comp_ctx->curr_func.in_scanning) {
+ duk_uarridx_t n;
+ duk_hstring *h_funcname;
+
+ duk_get_prop_index(ctx, comp_ctx->curr_func.funcs_idx, fnum * 3);
+ duk_get_prop_stridx(ctx, -1, DUK_STRIDX_NAME); /* -> [ ... func name ] */
+ h_funcname = duk_get_hstring(ctx, -1);
+ DUK_ASSERT(h_funcname != NULL);
+
+ DUK_DDD(DUK_DDDPRINT("register function declaration %!O in pass 1, fnum %ld",
+ (duk_heaphdr *) h_funcname, (long) fnum));
+ n = (duk_uarridx_t) duk_get_length(ctx, comp_ctx->curr_func.decls_idx);
+ duk_push_hstring(ctx, h_funcname);
+ duk_put_prop_index(ctx, comp_ctx->curr_func.decls_idx, n);
+ duk_push_int(ctx, (duk_int_t) (DUK_DECL_TYPE_FUNC + (fnum << 8)));
+ duk_put_prop_index(ctx, comp_ctx->curr_func.decls_idx, n + 1);
+
+ duk_pop_n(ctx, 2);
+ }
+
+ /* no statement value (unlike function expression) */
+ stmt_flags = 0;
+ break;
+ } else {
+ DUK_ERROR_SYNTAX(thr, DUK_STR_FUNC_STMT_NOT_ALLOWED);
+ }
+ break;
+ }
+ case DUK_TOK_LCURLY: {
+ DUK_DDD(DUK_DDDPRINT("block statement"));
+ duk__advance(comp_ctx);
+ duk__parse_stmts(comp_ctx, 0 /*allow_source_elem*/, 0 /*expect_eof*/);
+ /* the DUK_TOK_RCURLY is eaten by duk__parse_stmts() */
+ if (label_id >= 0) {
+ duk__patch_jump_here(comp_ctx, pc_at_entry + 1); /* break jump */
+ }
+ stmt_flags = 0;
+ break;
+ }
+ case DUK_TOK_CONST: {
+ DUK_DDD(DUK_DDDPRINT("constant declaration statement"));
+ duk__parse_var_stmt(comp_ctx, res, DUK__EXPR_FLAG_REQUIRE_INIT /*expr_flags*/);
+ stmt_flags = DUK__HAS_TERM;
+ break;
+ }
+ case DUK_TOK_VAR: {
+ DUK_DDD(DUK_DDDPRINT("variable declaration statement"));
+ duk__parse_var_stmt(comp_ctx, res, 0 /*expr_flags*/);
+ stmt_flags = DUK__HAS_TERM;
+ break;
+ }
+ case DUK_TOK_SEMICOLON: {
+ /* empty statement with an explicit semicolon */
+ DUK_DDD(DUK_DDDPRINT("empty statement"));
+ stmt_flags = DUK__HAS_TERM;
+ break;
+ }
+ case DUK_TOK_IF: {
+ DUK_DDD(DUK_DDDPRINT("if statement"));
+ duk__parse_if_stmt(comp_ctx, res);
+ if (label_id >= 0) {
+ duk__patch_jump_here(comp_ctx, pc_at_entry + 1); /* break jump */
+ }
+ stmt_flags = 0;
+ break;
+ }
+ case DUK_TOK_DO: {
+ /*
+ * Do-while statement is mostly trivial, but there is special
+ * handling for automatic semicolon handling (triggered by the
+ * DUK__ALLOW_AUTO_SEMI_ALWAYS) flag related to a bug filed at:
+ *
+ * https://bugs.ecmascript.org/show_bug.cgi?id=8
+ *
+ * See doc/compiler.rst for details.
+ */
+ DUK_DDD(DUK_DDDPRINT("do statement"));
+ DUK_ASSERT(label_id >= 0);
+ duk__update_label_flags(comp_ctx,
+ label_id,
+ DUK_LABEL_FLAG_ALLOW_BREAK | DUK_LABEL_FLAG_ALLOW_CONTINUE);
+ duk__parse_do_stmt(comp_ctx, res, pc_at_entry);
+ stmt_flags = DUK__HAS_TERM | DUK__ALLOW_AUTO_SEMI_ALWAYS; /* DUK__ALLOW_AUTO_SEMI_ALWAYS workaround */
+ break;
+ }
+ case DUK_TOK_WHILE: {
+ DUK_DDD(DUK_DDDPRINT("while statement"));
+ DUK_ASSERT(label_id >= 0);
+ duk__update_label_flags(comp_ctx,
+ label_id,
+ DUK_LABEL_FLAG_ALLOW_BREAK | DUK_LABEL_FLAG_ALLOW_CONTINUE);
+ duk__parse_while_stmt(comp_ctx, res, pc_at_entry);
+ stmt_flags = 0;
+ break;
+ }
+ case DUK_TOK_FOR: {
+ /*
+ * For/for-in statement is complicated to parse because
+ * determining the statement type (three-part for vs. a
+ * for-in) requires potential backtracking.
+ *
+ * See the helper for the messy stuff.
+ */
+ DUK_DDD(DUK_DDDPRINT("for/for-in statement"));
+ DUK_ASSERT(label_id >= 0);
+ duk__update_label_flags(comp_ctx,
+ label_id,
+ DUK_LABEL_FLAG_ALLOW_BREAK | DUK_LABEL_FLAG_ALLOW_CONTINUE);
+ duk__parse_for_stmt(comp_ctx, res, pc_at_entry);
+ stmt_flags = 0;
+ break;
+ }
+ case DUK_TOK_CONTINUE:
+ case DUK_TOK_BREAK: {
+ DUK_DDD(DUK_DDDPRINT("break/continue statement"));
+ duk__parse_break_or_continue_stmt(comp_ctx, res);
+ stmt_flags = DUK__HAS_TERM | DUK__IS_TERMINAL;
+ break;
+ }
+ case DUK_TOK_RETURN: {
+ DUK_DDD(DUK_DDDPRINT("return statement"));
+ duk__parse_return_stmt(comp_ctx, res);
+ stmt_flags = DUK__HAS_TERM | DUK__IS_TERMINAL;
+ break;
+ }
+ case DUK_TOK_WITH: {
+ DUK_DDD(DUK_DDDPRINT("with statement"));
+ comp_ctx->curr_func.with_depth++;
+ duk__parse_with_stmt(comp_ctx, res);
+ if (label_id >= 0) {
+ duk__patch_jump_here(comp_ctx, pc_at_entry + 1); /* break jump */
+ }
+ comp_ctx->curr_func.with_depth--;
+ stmt_flags = 0;
+ break;
+ }
+ case DUK_TOK_SWITCH: {
+ /*
+ * The switch statement is pretty messy to compile.
+ * See the helper for details.
+ */
+ DUK_DDD(DUK_DDDPRINT("switch statement"));
+ DUK_ASSERT(label_id >= 0);
+ duk__update_label_flags(comp_ctx,
+ label_id,
+ DUK_LABEL_FLAG_ALLOW_BREAK); /* don't allow continue */
+ duk__parse_switch_stmt(comp_ctx, res, pc_at_entry);
+ stmt_flags = 0;
+ break;
+ }
+ case DUK_TOK_THROW: {
+ DUK_DDD(DUK_DDDPRINT("throw statement"));
+ duk__parse_throw_stmt(comp_ctx, res);
+ stmt_flags = DUK__HAS_TERM | DUK__IS_TERMINAL;
+ break;
+ }
+ case DUK_TOK_TRY: {
+ DUK_DDD(DUK_DDDPRINT("try statement"));
+ duk__parse_try_stmt(comp_ctx, res);
+ stmt_flags = 0;
+ break;
+ }
+ case DUK_TOK_DEBUGGER: {
+ duk__advance(comp_ctx);
+#if defined(DUK_USE_DEBUGGER_SUPPORT)
+ DUK_DDD(DUK_DDDPRINT("debugger statement: debugging enabled, emit debugger opcode"));
+ duk__emit_extraop_only(comp_ctx, DUK_EXTRAOP_DEBUGGER);
+#else
+ DUK_DDD(DUK_DDDPRINT("debugger statement: ignored"));
+#endif
+ stmt_flags = DUK__HAS_TERM;
+ break;
+ }
+ default: {
+ /*
+ * Else, must be one of:
+ * - ExpressionStatement, possibly a directive (String)
+ * - LabelledStatement (Identifier followed by ':')
+ *
+ * Expressions beginning with 'function' keyword are covered by a case
+ * above (such expressions are not allowed in standard E5 anyway).
+ * Also expressions starting with '{' are interpreted as block
+ * statements. See E5 Section 12.4.
+ *
+ * Directive detection is tricky; see E5 Section 14.1 on directive
+ * prologue. A directive is an expression statement with a single
+ * string literal and an explicit or automatic semicolon. Escape
+ * characters are significant and no parens etc are allowed:
+ *
+ * 'use strict'; // valid 'use strict' directive
+ * 'use\u0020strict'; // valid directive, not a 'use strict' directive
+ * ('use strict'); // not a valid directive
+ *
+ * The expression is determined to consist of a single string literal
+ * based on duk__expr_nud() and duk__expr_led() call counts. The string literal
+ * of a 'use strict' directive is determined to lack any escapes based
+ * num_escapes count from the lexer. Note that other directives may be
+ * allowed to contain escapes, so a directive with escapes does not
+ * terminate a directive prologue.
+ *
+ * We rely on the fact that the expression parser will not emit any
+ * code for a single token expression. However, it will generate an
+ * intermediate value which we will then successfully ignore.
+ *
+ * A similar approach is used for labels.
+ */
+
+ duk_bool_t single_token;
+
+ DUK_DDD(DUK_DDDPRINT("expression statement"));
+ duk__exprtop(comp_ctx, res, DUK__BP_FOR_EXPR /*rbp_flags*/);
+
+ single_token = (comp_ctx->curr_func.nud_count == 1 && /* one token */
+ comp_ctx->curr_func.led_count == 0); /* no operators */
+
+ if (single_token &&
+ comp_ctx->prev_token.t == DUK_TOK_IDENTIFIER &&
+ comp_ctx->curr_token.t == DUK_TOK_COLON) {
+ /*
+ * Detected label
+ */
+
+ duk_hstring *h_lab;
+
+ /* expected ival */
+ DUK_ASSERT(res->t == DUK_IVAL_VAR);
+ DUK_ASSERT(res->x1.t == DUK_ISPEC_VALUE);
+ DUK_ASSERT(DUK_TVAL_IS_STRING(duk_get_tval(ctx, res->x1.valstack_idx)));
+ h_lab = comp_ctx->prev_token.str1;
+ DUK_ASSERT(h_lab != NULL);
+
+ DUK_DDD(DUK_DDDPRINT("explicit label site for label '%!O'",
+ (duk_heaphdr *) h_lab));
+
+ duk__advance(comp_ctx); /* eat colon */
+
+ label_id = duk__stmt_label_site(comp_ctx, label_id);
+
+ duk__add_label(comp_ctx,
+ h_lab,
+ pc_at_entry /*pc_label*/,
+ label_id);
+
+ /* a statement following a label cannot be a source element
+ * (a function declaration).
+ */
+ allow_source_elem = 0;
+
+ DUK_DDD(DUK_DDDPRINT("label handled, retry statement parsing"));
+ goto retry_parse;
+ }
+
+ stmt_flags = 0;
+
+ if (dir_prol_at_entry && /* still in prologue */
+ single_token && /* single string token */
+ comp_ctx->prev_token.t == DUK_TOK_STRING) {
+ /*
+ * Detected a directive
+ */
+ duk_hstring *h_dir;
+
+ /* expected ival */
+ DUK_ASSERT(res->t == DUK_IVAL_PLAIN);
+ DUK_ASSERT(res->x1.t == DUK_ISPEC_VALUE);
+ DUK_ASSERT(DUK_TVAL_IS_STRING(duk_get_tval(ctx, res->x1.valstack_idx)));
+ h_dir = comp_ctx->prev_token.str1;
+ DUK_ASSERT(h_dir != NULL);
+
+ DUK_DDD(DUK_DDDPRINT("potential directive: %!O", h_dir));
+
+ stmt_flags |= DUK__STILL_PROLOGUE;
+
+ /* Note: escaped characters differentiate directives */
+
+ if (comp_ctx->prev_token.num_escapes > 0) {
+ DUK_DDD(DUK_DDDPRINT("directive contains escapes: valid directive "
+ "but we ignore such directives"));
+ } else {
+ /*
+ * The length comparisons are present to handle
+ * strings like "use strict\u0000foo" as required.
+ */
+
+ if (DUK_HSTRING_GET_BYTELEN(h_dir) == 10 &&
+ DUK_STRNCMP((const char *) DUK_HSTRING_GET_DATA(h_dir), "use strict", 10) == 0) {
+#if defined(DUK_USE_STRICT_DECL)
+ DUK_DDD(DUK_DDDPRINT("use strict directive detected: strict flag %ld -> %ld",
+ (long) comp_ctx->curr_func.is_strict, (long) 1));
+ comp_ctx->curr_func.is_strict = 1;
+#else
+ DUK_DDD(DUK_DDDPRINT("use strict detected but strict declarations disabled, ignoring"));
+#endif
+ } else if (DUK_HSTRING_GET_BYTELEN(h_dir) == 14 &&
+ DUK_STRNCMP((const char *) DUK_HSTRING_GET_DATA(h_dir), "use duk notail", 14) == 0) {
+ DUK_DDD(DUK_DDDPRINT("use duk notail directive detected: notail flag %ld -> %ld",
+ (long) comp_ctx->curr_func.is_notail, (long) 1));
+ comp_ctx->curr_func.is_notail = 1;
+ } else {
+ DUK_DD(DUK_DDPRINT("unknown directive: '%!O', ignoring but not terminating "
+ "directive prologue", (duk_hobject *) h_dir));
+ }
+ }
+ } else {
+ DUK_DDD(DUK_DDDPRINT("non-directive expression statement or no longer in prologue; "
+ "prologue terminated if still active"));
+ }
+
+ stmt_flags |= DUK__HAS_VAL | DUK__HAS_TERM;
+ }
+ } /* end switch (tok) */
+
+ /*
+ * Statement value handling.
+ *
+ * Global code and eval code has an implicit return value
+ * which comes from the last statement with a value
+ * (technically a non-"empty" continuation, which is
+ * different from an empty statement).
+ *
+ * Since we don't know whether a later statement will
+ * override the value of the current statement, we need
+ * to coerce the statement value to a register allocated
+ * for implicit return values. In other cases we need
+ * to coerce the statement value to a plain value to get
+ * any side effects out (consider e.g. "foo.bar;").
+ */
+
+ /* XXX: what about statements which leave a half-cooked value in 'res'
+ * but have no stmt value? Any such statements?
+ */
+
+ if (stmt_flags & DUK__HAS_VAL) {
+ duk_reg_t reg_stmt_value = comp_ctx->curr_func.reg_stmt_value;
+ if (reg_stmt_value >= 0) {
+ duk__ivalue_toforcedreg(comp_ctx, res, reg_stmt_value);
+ } else {
+ duk__ivalue_toplain_ignore(comp_ctx, res);
+ }
+ } else {
+ ;
+ }
+
+ /*
+ * Statement terminator check, including automatic semicolon
+ * handling. After this step, 'curr_tok' should be the first
+ * token after a possible statement terminator.
+ */
+
+ if (stmt_flags & DUK__HAS_TERM) {
+ if (comp_ctx->curr_token.t == DUK_TOK_SEMICOLON) {
+ DUK_DDD(DUK_DDDPRINT("explicit semicolon terminates statement"));
+ duk__advance(comp_ctx);
+ } else {
+ if (comp_ctx->curr_token.allow_auto_semi) {
+ DUK_DDD(DUK_DDDPRINT("automatic semicolon terminates statement"));
+ } else if (stmt_flags & DUK__ALLOW_AUTO_SEMI_ALWAYS) {
+ /* XXX: make this lenience dependent on flags or strictness? */
+ DUK_DDD(DUK_DDDPRINT("automatic semicolon terminates statement (allowed for compatibility "
+ "even though no lineterm present before next token)"));
+ } else {
+ DUK_ERROR_SYNTAX(thr, DUK_STR_UNTERMINATED_STMT);
+ }
+ }
+ } else {
+ DUK_DDD(DUK_DDDPRINT("statement has no terminator"));
+ }
+
+ /*
+ * Directive prologue tracking.
+ */
+
+ if (stmt_flags & DUK__STILL_PROLOGUE) {
+ DUK_DDD(DUK_DDDPRINT("setting in_directive_prologue"));
+ comp_ctx->curr_func.in_directive_prologue = 1;
+ }
+
+ /*
+ * Cleanups (all statement parsing flows through here).
+ *
+ * Pop label site and reset labels. Reset 'next temp' to value at
+ * entry to reuse temps.
+ */
+
+ if (label_id >= 0) {
+ duk__emit_extraop_bc(comp_ctx,
+ DUK_EXTRAOP_ENDLABEL,
+ (duk_regconst_t) label_id);
+ }
+
+ DUK__SETTEMP(comp_ctx, temp_at_entry);
+
+ duk__reset_labels_to_length(comp_ctx, labels_len_at_entry);
+
+ /* XXX: return indication of "terminalness" (e.g. a 'throw' is terminal) */
+
+ DUK__RECURSION_DECREASE(comp_ctx, thr);
+}
+
+#undef DUK__HAS_VAL
+#undef DUK__HAS_TERM
+#undef DUK__ALLOW_AUTO_SEMI_ALWAYS
+
+/*
+ * Parse a statement list.
+ *
+ * Handles automatic semicolon insertion and implicit return value.
+ *
+ * Upon entry, 'curr_tok' should contain the first token of the first
+ * statement (parsed in the "allow regexp literal" mode). Upon exit,
+ * 'curr_tok' contains the token following the statement list terminator
+ * (EOF or closing brace).
+ */
+
+DUK_LOCAL void duk__parse_stmts(duk_compiler_ctx *comp_ctx, duk_bool_t allow_source_elem, duk_bool_t expect_eof) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_ivalue res_alloc;
+ duk_ivalue *res = &res_alloc;
+
+ /* Setup state. Initial ivalue is 'undefined'. */
+
+ duk_require_stack(ctx, DUK__PARSE_STATEMENTS_SLOTS);
+
+ /* XXX: 'res' setup can be moved to function body level; in fact, two 'res'
+ * intermediate values suffice for parsing of each function. Nesting is needed
+ * for nested functions (which may occur inside expressions).
+ */
+
+ DUK_MEMZERO(&res_alloc, sizeof(res_alloc));
+ res->t = DUK_IVAL_PLAIN;
+ res->x1.t = DUK_ISPEC_VALUE;
+ res->x1.valstack_idx = duk_get_top(ctx);
+ res->x2.valstack_idx = res->x1.valstack_idx + 1;
+ duk_push_undefined(ctx);
+ duk_push_undefined(ctx);
+
+ /* Parse statements until a closing token (EOF or '}') is found. */
+
+ for (;;) {
+ /* Check whether statement list ends. */
+
+ if (expect_eof) {
+ if (comp_ctx->curr_token.t == DUK_TOK_EOF) {
+ break;
+ }
+ } else {
+ if (comp_ctx->curr_token.t == DUK_TOK_RCURLY) {
+ break;
+ }
+ }
+
+ /* Check statement type based on the first token type.
+ *
+ * Note: expression parsing helpers expect 'curr_tok' to
+ * contain the first token of the expression upon entry.
+ */
+
+ DUK_DDD(DUK_DDDPRINT("TOKEN %ld (non-whitespace, non-comment)", (long) comp_ctx->curr_token.t));
+
+ duk__parse_stmt(comp_ctx, res, allow_source_elem);
+ }
+
+ duk__advance(comp_ctx);
+
+ /* Tear down state. */
+
+ duk_pop_2(ctx);
+}
+
+/*
+ * Declaration binding instantiation conceptually happens when calling a
+ * function; for us it essentially means that function prologue. The
+ * conceptual process is described in E5 Section 10.5.
+ *
+ * We need to keep track of all encountered identifiers to (1) create an
+ * identifier-to-register map ("varmap"); and (2) detect duplicate
+ * declarations. Identifiers which are not bound to registers still need
+ * to be tracked for detecting duplicates. Currently such identifiers
+ * are put into the varmap with a 'null' value, which is later cleaned up.
+ *
+ * To support functions with a large number of variable and function
+ * declarations, registers are not allocated beyond a certain limit;
+ * after that limit, variables and functions need slow path access.
+ * Arguments are currently always register bound, which imposes a hard
+ * (and relatively small) argument count limit.
+ *
+ * Some bindings in E5 are not configurable (= deletable) and almost all
+ * are mutable (writable). Exceptions are:
+ *
+ * - The 'arguments' binding, established only if no shadowing argument
+ * or function declaration exists. We handle 'arguments' creation
+ * and binding through an explicit slow path environment record.
+ *
+ * - The "name" binding for a named function expression. This is also
+ * handled through an explicit slow path environment record.
+ */
+
+/* XXX: add support for variables to not be register bound always, to
+ * handle cases with a very large number of variables?
+ */
+
+DUK_LOCAL void duk__init_varmap_and_prologue_for_pass2(duk_compiler_ctx *comp_ctx, duk_reg_t *out_stmt_value_reg) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_hstring *h_name;
+ duk_bool_t configurable_bindings;
+ duk_uarridx_t num_args;
+ duk_uarridx_t num_decls;
+ duk_regconst_t rc_name;
+ duk_small_uint_t declvar_flags;
+ duk_uarridx_t i;
+#ifdef DUK_USE_ASSERTIONS
+ duk_idx_t entry_top;
+#endif
+
+#ifdef DUK_USE_ASSERTIONS
+ entry_top = duk_get_top(ctx);
+#endif
+
+ /*
+ * Preliminaries
+ */
+
+ configurable_bindings = comp_ctx->curr_func.is_eval;
+ DUK_DDD(DUK_DDDPRINT("configurable_bindings=%ld", (long) configurable_bindings));
+
+ /* varmap is already in comp_ctx->curr_func.varmap_idx */
+
+ /*
+ * Function formal arguments, always bound to registers
+ * (there's no support for shuffling them now).
+ */
+
+ num_args = (duk_uarridx_t) duk_get_length(ctx, comp_ctx->curr_func.argnames_idx);
+ DUK_DDD(DUK_DDDPRINT("num_args=%ld", (long) num_args));
+ /* XXX: check num_args */
+
+ for (i = 0; i < num_args; i++) {
+ duk_get_prop_index(ctx, comp_ctx->curr_func.argnames_idx, i);
+ h_name = duk_get_hstring(ctx, -1);
+ DUK_ASSERT(h_name != NULL);
+
+ if (comp_ctx->curr_func.is_strict) {
+ if (duk__hstring_is_eval_or_arguments(comp_ctx, h_name)) {
+ DUK_DDD(DUK_DDDPRINT("arg named 'eval' or 'arguments' in strict mode -> SyntaxError"));
+ goto error_argname;
+ }
+ duk_dup_top(ctx);
+ if (duk_has_prop(ctx, comp_ctx->curr_func.varmap_idx)) {
+ DUK_DDD(DUK_DDDPRINT("duplicate arg name in strict mode -> SyntaxError"));
+ goto error_argname;
+ }
+
+ /* Ensure argument name is not a reserved word in current
+ * (final) strictness. Formal argument parsing may not
+ * catch reserved names if strictness changes during
+ * parsing.
+ *
+ * We only need to do this in strict mode because non-strict
+ * keyword are always detected in formal argument parsing.
+ */
+
+ if (DUK_HSTRING_HAS_STRICT_RESERVED_WORD(h_name)) {
+ goto error_argname;
+ }
+ }
+
+ /* overwrite any previous binding of the same name; the effect is
+ * that last argument of a certain name wins.
+ */
+
+ /* only functions can have arguments */
+ DUK_ASSERT(comp_ctx->curr_func.is_function);
+ duk_push_uarridx(ctx, i); /* -> [ ... name index ] */
+ duk_put_prop(ctx, comp_ctx->curr_func.varmap_idx); /* -> [ ... ] */
+
+ /* no code needs to be emitted, the regs already have values */
+ }
+
+ /* use temp_next for tracking register allocations */
+ DUK__SETTEMP_CHECKMAX(comp_ctx, (duk_reg_t) num_args);
+
+ /*
+ * After arguments, allocate special registers (like shuffling temps)
+ */
+
+ if (out_stmt_value_reg) {
+ *out_stmt_value_reg = DUK__ALLOCTEMP(comp_ctx);
+ }
+ if (comp_ctx->curr_func.needs_shuffle) {
+ duk_reg_t shuffle_base = DUK__ALLOCTEMPS(comp_ctx, 3);
+ comp_ctx->curr_func.shuffle1 = shuffle_base;
+ comp_ctx->curr_func.shuffle2 = shuffle_base + 1;
+ comp_ctx->curr_func.shuffle3 = shuffle_base + 2;
+ DUK_D(DUK_DPRINT("shuffle registers needed by function, allocated: %ld %ld %ld",
+ (long) comp_ctx->curr_func.shuffle1,
+ (long) comp_ctx->curr_func.shuffle2,
+ (long) comp_ctx->curr_func.shuffle3));
+ }
+ if (comp_ctx->curr_func.temp_next > 0x100) {
+ DUK_D(DUK_DPRINT("not enough 8-bit regs: temp_next=%ld", (long) comp_ctx->curr_func.temp_next));
+ goto error_outofregs;
+ }
+
+ /*
+ * Function declarations
+ */
+
+ num_decls = (duk_uarridx_t) duk_get_length(ctx, comp_ctx->curr_func.decls_idx);
+ DUK_DDD(DUK_DDDPRINT("num_decls=%ld -> %!T",
+ (long) num_decls,
+ (duk_tval *) duk_get_tval(ctx, comp_ctx->curr_func.decls_idx)));
+ for (i = 0; i < num_decls; i += 2) {
+ duk_int_t decl_type;
+ duk_int_t fnum;
+
+ duk_get_prop_index(ctx, comp_ctx->curr_func.decls_idx, i + 1); /* decl type */
+ decl_type = duk_to_int(ctx, -1);
+ fnum = decl_type >> 8; /* XXX: macros */
+ decl_type = decl_type & 0xff;
+ duk_pop(ctx);
+
+ if (decl_type != DUK_DECL_TYPE_FUNC) {
+ continue;
+ }
+
+ duk_get_prop_index(ctx, comp_ctx->curr_func.decls_idx, i); /* decl name */
+
+ /* XXX: spilling */
+ if (comp_ctx->curr_func.is_function) {
+ duk_reg_t reg_bind;
+ duk_dup_top(ctx);
+ if (duk_has_prop(ctx, comp_ctx->curr_func.varmap_idx)) {
+ /* shadowed; update value */
+ duk_dup_top(ctx);
+ duk_get_prop(ctx, comp_ctx->curr_func.varmap_idx);
+ reg_bind = duk_to_int(ctx, -1); /* [ ... name reg_bind ] */
+ duk__emit_a_bc(comp_ctx,
+ DUK_OP_CLOSURE,
+ (duk_regconst_t) reg_bind,
+ (duk_regconst_t) fnum);
+ } else {
+ /* function: always register bound */
+ reg_bind = DUK__ALLOCTEMP(comp_ctx);
+ duk__emit_a_bc(comp_ctx,
+ DUK_OP_CLOSURE,
+ (duk_regconst_t) reg_bind,
+ (duk_regconst_t) fnum);
+ duk_push_int(ctx, (duk_int_t) reg_bind);
+ }
+ } else {
+ /* Function declaration for global/eval code is emitted even
+ * for duplicates, because of E5 Section 10.5, step 5.e of
+ * E5.1 (special behavior for variable bound to global object).
+ *
+ * DECLVAR will not re-declare a variable as such, but will
+ * update the binding value.
+ */
+
+ duk_reg_t reg_temp = DUK__ALLOCTEMP(comp_ctx);
+ duk_dup_top(ctx);
+ rc_name = duk__getconst(comp_ctx);
+ duk_push_null(ctx);
+
+ duk__emit_a_bc(comp_ctx,
+ DUK_OP_CLOSURE,
+ (duk_regconst_t) reg_temp,
+ (duk_regconst_t) fnum);
+
+ declvar_flags = DUK_PROPDESC_FLAG_WRITABLE |
+ DUK_PROPDESC_FLAG_ENUMERABLE |
+ DUK_BC_DECLVAR_FLAG_FUNC_DECL;
+
+ if (configurable_bindings) {
+ declvar_flags |= DUK_PROPDESC_FLAG_CONFIGURABLE;
+ }
+
+ duk__emit_a_b_c(comp_ctx,
+ DUK_OP_DECLVAR | DUK__EMIT_FLAG_NO_SHUFFLE_A,
+ (duk_regconst_t) declvar_flags /*flags*/,
+ rc_name /*name*/,
+ (duk_regconst_t) reg_temp /*value*/);
+
+ DUK__SETTEMP(comp_ctx, reg_temp); /* forget temp */
+ }
+
+ DUK_DDD(DUK_DDDPRINT("function declaration to varmap: %!T -> %!T",
+ (duk_tval *) duk_get_tval(ctx, -2),
+ (duk_tval *) duk_get_tval(ctx, -1)));
+
+ duk_put_prop(ctx, comp_ctx->curr_func.varmap_idx); /* [ ... name reg/null ] -> [ ... ] */
+ }
+
+ /*
+ * 'arguments' binding is special; if a shadowing argument or
+ * function declaration exists, an arguments object will
+ * definitely not be needed, regardless of whether the identifier
+ * 'arguments' is referenced inside the function body.
+ */
+
+ if (duk_has_prop_stridx(ctx, comp_ctx->curr_func.varmap_idx, DUK_STRIDX_LC_ARGUMENTS)) {
+ DUK_DDD(DUK_DDDPRINT("'arguments' is shadowed by argument or function declaration "
+ "-> arguments object creation can be skipped"));
+ comp_ctx->curr_func.is_arguments_shadowed = 1;
+ }
+
+ /*
+ * Variable declarations.
+ *
+ * Unlike function declarations, variable declaration values don't get
+ * assigned on entry. If a binding of the same name already exists, just
+ * ignore it silently.
+ */
+
+ for (i = 0; i < num_decls; i += 2) {
+ duk_int_t decl_type;
+
+ duk_get_prop_index(ctx, comp_ctx->curr_func.decls_idx, i + 1); /* decl type */
+ decl_type = duk_to_int(ctx, -1);
+ decl_type = decl_type & 0xff;
+ duk_pop(ctx);
+
+ if (decl_type != DUK_DECL_TYPE_VAR) {
+ continue;
+ }
+
+ duk_get_prop_index(ctx, comp_ctx->curr_func.decls_idx, i); /* decl name */
+
+ if (duk_has_prop(ctx, comp_ctx->curr_func.varmap_idx)) {
+ /* shadowed, ignore */
+ } else {
+ duk_get_prop_index(ctx, comp_ctx->curr_func.decls_idx, i); /* decl name */
+ h_name = duk_get_hstring(ctx, -1);
+ DUK_ASSERT(h_name != NULL);
+
+ if (h_name == DUK_HTHREAD_STRING_LC_ARGUMENTS(thr) &&
+ !comp_ctx->curr_func.is_arguments_shadowed) {
+ /* E5 Section steps 7-8 */
+ DUK_DDD(DUK_DDDPRINT("'arguments' not shadowed by a function declaration, "
+ "but appears as a variable declaration -> treat as "
+ "a no-op for variable declaration purposes"));
+ duk_pop(ctx);
+ continue;
+ }
+
+ /* XXX: spilling */
+ if (comp_ctx->curr_func.is_function) {
+ duk_reg_t reg_bind = DUK__ALLOCTEMP(comp_ctx);
+ /* no need to init reg, it will be undefined on entry */
+ duk_push_int(ctx, (duk_int_t) reg_bind);
+ } else {
+ duk_dup_top(ctx);
+ rc_name = duk__getconst(comp_ctx);
+ duk_push_null(ctx);
+
+ declvar_flags = DUK_PROPDESC_FLAG_WRITABLE |
+ DUK_PROPDESC_FLAG_ENUMERABLE |
+ DUK_BC_DECLVAR_FLAG_UNDEF_VALUE;
+ if (configurable_bindings) {
+ declvar_flags |= DUK_PROPDESC_FLAG_CONFIGURABLE;
+ }
+
+ duk__emit_a_b_c(comp_ctx,
+ DUK_OP_DECLVAR | DUK__EMIT_FLAG_NO_SHUFFLE_A,
+ (duk_regconst_t) declvar_flags /*flags*/,
+ rc_name /*name*/,
+ (duk_regconst_t) 0 /*value*/);
+ }
+
+ duk_put_prop(ctx, comp_ctx->curr_func.varmap_idx); /* [ ... name reg/null ] -> [ ... ] */
+ }
+ }
+
+ /*
+ * Wrap up
+ */
+
+ DUK_DDD(DUK_DDDPRINT("varmap: %!T, is_arguments_shadowed=%ld",
+ (duk_tval *) duk_get_tval(ctx, comp_ctx->curr_func.varmap_idx),
+ (long) comp_ctx->curr_func.is_arguments_shadowed));
+
+ DUK_ASSERT_TOP(ctx, entry_top);
+ return;
+
+ error_outofregs:
+ DUK_ERROR_RANGE(thr, DUK_STR_REG_LIMIT);
+ DUK_UNREACHABLE();
+ return;
+
+ error_argname:
+ DUK_ERROR_SYNTAX(thr, DUK_STR_INVALID_ARG_NAME);
+ DUK_UNREACHABLE();
+ return;
+}
+
+/*
+ * Parse a function-body-like expression (FunctionBody or Program
+ * in E5 grammar) using a two-pass parse. The productions appear
+ * in the following contexts:
+ *
+ * - function expression
+ * - function statement
+ * - function declaration
+ * - getter in object literal
+ * - setter in object literal
+ * - global code
+ * - eval code
+ * - Function constructor body
+ *
+ * This function only parses the statement list of the body; the argument
+ * list and possible function name must be initialized by the caller.
+ * For instance, for Function constructor, the argument names are originally
+ * on the value stack. The parsing of statements ends either at an EOF or
+ * a closing brace; this is controlled by an input flag.
+ *
+ * Note that there are many differences affecting parsing and even code
+ * generation:
+ *
+ * - Global and eval code have an implicit return value generated
+ * by the last statement; function code does not
+ *
+ * - Global code, eval code, and Function constructor body end in
+ * an EOF, other bodies in a closing brace ('}')
+ *
+ * Upon entry, 'curr_tok' is ignored and the function will pull in the
+ * first token on its own. Upon exit, 'curr_tok' is the terminating
+ * token (EOF or closing brace).
+ */
+
+DUK_LOCAL void duk__parse_func_body(duk_compiler_ctx *comp_ctx, duk_bool_t expect_eof, duk_bool_t implicit_return_value, duk_small_int_t expect_token) {
+ duk_compiler_func *func;
+ duk_hthread *thr;
+ duk_context *ctx;
+ duk_reg_t reg_stmt_value = -1;
+ duk_lexer_point lex_pt;
+ duk_reg_t temp_first;
+ duk_small_int_t compile_round = 1;
+
+ DUK_ASSERT(comp_ctx != NULL);
+
+ thr = comp_ctx->thr;
+ ctx = (duk_context *) thr;
+ DUK_ASSERT(thr != NULL);
+
+ func = &comp_ctx->curr_func;
+ DUK_ASSERT(func != NULL);
+
+ DUK__RECURSION_INCREASE(comp_ctx, thr);
+
+ duk_require_stack(ctx, DUK__FUNCTION_BODY_REQUIRE_SLOTS);
+
+ /*
+ * Store lexer position for a later rewind
+ */
+
+ DUK_LEXER_GETPOINT(&comp_ctx->lex, &lex_pt);
+
+ /*
+ * Program code (global and eval code) has an implicit return value
+ * from the last statement value (e.g. eval("1; 2+3;") returns 3).
+ * This is not the case with functions. If implicit statement return
+ * value is requested, all statements are coerced to a register
+ * allocated here, and used in the implicit return statement below.
+ */
+
+ /* XXX: this is pointless here because pass 1 is throw-away */
+ if (implicit_return_value) {
+ reg_stmt_value = DUK__ALLOCTEMP(comp_ctx);
+
+ /* If an implicit return value is needed by caller, it must be
+ * initialized to 'undefined' because we don't know whether any
+ * non-empty (where "empty" is a continuation type, and different
+ * from an empty statement) statements will be executed.
+ *
+ * However, since 1st pass is a throwaway one, no need to emit
+ * it here.
+ */
+#if 0
+ duk__emit_extraop_bc(comp_ctx,
+ DUK_EXTRAOP_LDUNDEF,
+ 0);
+#endif
+ }
+
+ /*
+ * First pass.
+ *
+ * Gather variable/function declarations needed for second pass.
+ * Code generated is dummy and discarded.
+ */
+
+ func->in_directive_prologue = 1;
+ func->in_scanning = 1;
+ func->may_direct_eval = 0;
+ func->id_access_arguments = 0;
+ func->id_access_slow = 0;
+ func->reg_stmt_value = reg_stmt_value;
+#if defined(DUK_USE_DEBUGGER_SUPPORT)
+ func->min_line = DUK_INT_MAX;
+ func->max_line = 0;
+#endif
+
+ /* duk__parse_stmts() expects curr_tok to be set; parse in "allow regexp literal" mode with current strictness */
+ if (expect_token >= 0) {
+ /* Eating a left curly; regexp mode is allowed by left curly
+ * based on duk__token_lbp[] automatically.
+ */
+ DUK_ASSERT(expect_token == DUK_TOK_LCURLY);
+ duk__update_lineinfo_currtoken(comp_ctx);
+ duk__advance_expect(comp_ctx, expect_token);
+ } else {
+ /* Need to set curr_token.t because lexing regexp mode depends on current
+ * token type. Zero value causes "allow regexp" mode.
+ */
+ comp_ctx->curr_token.t = 0;
+ duk__advance(comp_ctx);
+ }
+
+ DUK_DDD(DUK_DDDPRINT("begin 1st pass"));
+ duk__parse_stmts(comp_ctx,
+ 1, /* allow source elements */
+ expect_eof); /* expect EOF instead of } */
+ DUK_DDD(DUK_DDDPRINT("end 1st pass"));
+
+ /*
+ * Second (and possibly third) pass.
+ *
+ * Generate actual code. In most cases the need for shuffle
+ * registers is detected during pass 1, but in some corner cases
+ * we'll only detect it during pass 2 and a third pass is then
+ * needed (see GH-115).
+ */
+
+ for (;;) {
+ duk_bool_t needs_shuffle_before = comp_ctx->curr_func.needs_shuffle;
+ compile_round++;
+
+ /*
+ * Rewind lexer.
+ *
+ * duk__parse_stmts() expects curr_tok to be set; parse in "allow regexp
+ * literal" mode with current strictness.
+ *
+ * curr_token line number info should be initialized for pass 2 before
+ * generating prologue, to ensure prologue bytecode gets nice line numbers.
+ */
+
+ DUK_DDD(DUK_DDDPRINT("rewind lexer"));
+ DUK_LEXER_SETPOINT(&comp_ctx->lex, &lex_pt);
+ comp_ctx->curr_token.t = 0; /* this is needed for regexp mode */
+ comp_ctx->curr_token.start_line = 0; /* needed for line number tracking (becomes prev_token.start_line) */
+ duk__advance(comp_ctx);
+
+ /*
+ * Reset function state and perform register allocation, which creates
+ * 'varmap' for second pass. Function prologue for variable declarations,
+ * binding value initializations etc is emitted as a by-product.
+ *
+ * Strict mode restrictions for duplicate and invalid argument
+ * names are checked here now that we know whether the function
+ * is actually strict. See: test-dev-strict-mode-boundary.js.
+ *
+ * Inner functions are compiled during pass 1 and are not reset.
+ */
+
+ duk__reset_func_for_pass2(comp_ctx);
+ func->in_directive_prologue = 1;
+ func->in_scanning = 0;
+
+ /* must be able to emit code, alloc consts, etc. */
+
+ duk__init_varmap_and_prologue_for_pass2(comp_ctx,
+ (implicit_return_value ? ®_stmt_value : NULL));
+ func->reg_stmt_value = reg_stmt_value;
+
+ temp_first = DUK__GETTEMP(comp_ctx);
+
+ func->temp_first = temp_first;
+ func->temp_next = temp_first;
+ func->stmt_next = 0;
+ func->label_next = 0;
+
+ /* XXX: init or assert catch depth etc -- all values */
+ func->id_access_arguments = 0;
+ func->id_access_slow = 0;
+
+ /*
+ * Check function name validity now that we know strictness.
+ * This only applies to function declarations and expressions,
+ * not setter/getter name.
+ *
+ * See: test-dev-strict-mode-boundary.js
+ */
+
+ if (func->is_function && !func->is_setget && func->h_name != NULL) {
+ if (func->is_strict) {
+ if (duk__hstring_is_eval_or_arguments(comp_ctx, func->h_name)) {
+ DUK_DDD(DUK_DDDPRINT("func name is 'eval' or 'arguments' in strict mode"));
+ goto error_funcname;
+ }
+ if (DUK_HSTRING_HAS_STRICT_RESERVED_WORD(func->h_name)) {
+ DUK_DDD(DUK_DDDPRINT("func name is a reserved word in strict mode"));
+ goto error_funcname;
+ }
+ } else {
+ if (DUK_HSTRING_HAS_RESERVED_WORD(func->h_name) &&
+ !DUK_HSTRING_HAS_STRICT_RESERVED_WORD(func->h_name)) {
+ DUK_DDD(DUK_DDDPRINT("func name is a reserved word in non-strict mode"));
+ goto error_funcname;
+ }
+ }
+ }
+
+ /*
+ * Second pass parsing.
+ */
+
+ if (implicit_return_value) {
+ /* Default implicit return value. */
+ duk__emit_extraop_bc(comp_ctx,
+ DUK_EXTRAOP_LDUNDEF,
+ 0);
+ }
+
+ DUK_DDD(DUK_DDDPRINT("begin 2nd pass"));
+ duk__parse_stmts(comp_ctx,
+ 1, /* allow source elements */
+ expect_eof); /* expect EOF instead of } */
+ DUK_DDD(DUK_DDDPRINT("end 2nd pass"));
+
+ duk__update_lineinfo_currtoken(comp_ctx);
+
+ if (needs_shuffle_before == comp_ctx->curr_func.needs_shuffle) {
+ /* Shuffle decision not changed. */
+ break;
+ }
+ if (compile_round >= 3) {
+ /* Should never happen but avoid infinite loop just in case. */
+ DUK_D(DUK_DPRINT("more than 3 compile passes needed, should never happen"));
+ DUK_ERROR_INTERNAL_DEFMSG(thr);
+ }
+ DUK_D(DUK_DPRINT("need additional round to compile function, round now %d", (int) compile_round));
+ }
+
+ /*
+ * Emit a final RETURN.
+ *
+ * It would be nice to avoid emitting an unnecessary "return" opcode
+ * if the current PC is not reachable. However, this cannot be reliably
+ * detected; even if the previous instruction is an unconditional jump,
+ * there may be a previous jump which jumps to current PC (which is the
+ * case for iteration and conditional statements, for instance).
+ */
+
+ /* XXX: request a "last statement is terminal" from duk__parse_stmt() and duk__parse_stmts();
+ * we could avoid the last RETURN if we could ensure there is no way to get here
+ * (directly or via a jump)
+ */
+
+ DUK_ASSERT(comp_ctx->curr_func.catch_depth == 0);
+ if (reg_stmt_value >= 0) {
+ duk__emit_a_b(comp_ctx,
+ DUK_OP_RETURN | DUK__EMIT_FLAG_NO_SHUFFLE_A,
+ (duk_regconst_t) DUK_BC_RETURN_FLAG_HAVE_RETVAL /*flags*/,
+ (duk_regconst_t) reg_stmt_value /*reg*/);
+ } else {
+ duk__emit_a_b(comp_ctx,
+ DUK_OP_RETURN | DUK__EMIT_FLAG_NO_SHUFFLE_A,
+ (duk_regconst_t) 0 /*flags*/,
+ (duk_regconst_t) 0 /*reg(ignored)*/);
+ }
+
+ /*
+ * Peephole optimize JUMP chains.
+ */
+
+ duk__peephole_optimize_bytecode(comp_ctx);
+
+ /*
+ * comp_ctx->curr_func is now ready to be converted into an actual
+ * function template.
+ */
+
+ DUK__RECURSION_DECREASE(comp_ctx, thr);
+ return;
+
+ error_funcname:
+ DUK_ERROR_SYNTAX(thr, DUK_STR_INVALID_FUNC_NAME);
+}
+
+/*
+ * Parse a function-like expression:
+ *
+ * - function expression
+ * - function declaration
+ * - function statement (non-standard)
+ * - setter/getter
+ *
+ * Adds the function to comp_ctx->curr_func function table and returns the
+ * function number.
+ *
+ * On entry, curr_token points to:
+ *
+ * - the token after 'function' for function expression/declaration/statement
+ * - the token after 'set' or 'get' for setter/getter
+ */
+
+/* Parse formals. */
+DUK_LOCAL void duk__parse_func_formals(duk_compiler_ctx *comp_ctx) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_bool_t first = 1;
+ duk_uarridx_t n;
+
+ for (;;) {
+ if (comp_ctx->curr_token.t == DUK_TOK_RPAREN) {
+ break;
+ }
+
+ if (first) {
+ /* no comma */
+ first = 0;
+ } else {
+ duk__advance_expect(comp_ctx, DUK_TOK_COMMA);
+ }
+
+ /* Note: when parsing a formal list in non-strict context, e.g.
+ * "implements" is parsed as an identifier. When the function is
+ * later detected to be strict, the argument list must be rechecked
+ * against a larger set of reserved words (that of strict mode).
+ * This is handled by duk__parse_func_body(). Here we recognize
+ * whatever tokens are considered reserved in current strictness
+ * (which is not always enough).
+ */
+
+ if (comp_ctx->curr_token.t != DUK_TOK_IDENTIFIER) {
+ DUK_ERROR_SYNTAX(thr, "expected identifier");
+ }
+ DUK_ASSERT(comp_ctx->curr_token.t == DUK_TOK_IDENTIFIER);
+ DUK_ASSERT(comp_ctx->curr_token.str1 != NULL);
+ DUK_DDD(DUK_DDDPRINT("formal argument: %!O",
+ (duk_heaphdr *) comp_ctx->curr_token.str1));
+
+ /* XXX: append primitive */
+ duk_push_hstring(ctx, comp_ctx->curr_token.str1);
+ n = (duk_uarridx_t) duk_get_length(ctx, comp_ctx->curr_func.argnames_idx);
+ duk_put_prop_index(ctx, comp_ctx->curr_func.argnames_idx, n);
+
+ duk__advance(comp_ctx); /* eat identifier */
+ }
+}
+
+/* Parse a function-like expression, assuming that 'comp_ctx->curr_func' is
+ * correctly set up. Assumes that curr_token is just after 'function' (or
+ * 'set'/'get' etc).
+ */
+DUK_LOCAL void duk__parse_func_like_raw(duk_compiler_ctx *comp_ctx, duk_bool_t is_decl, duk_bool_t is_setget) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+
+ DUK_ASSERT(comp_ctx->curr_func.num_formals == 0);
+ DUK_ASSERT(comp_ctx->curr_func.is_function == 1);
+ DUK_ASSERT(comp_ctx->curr_func.is_eval == 0);
+ DUK_ASSERT(comp_ctx->curr_func.is_global == 0);
+ DUK_ASSERT(comp_ctx->curr_func.is_setget == is_setget);
+ DUK_ASSERT(comp_ctx->curr_func.is_decl == is_decl);
+
+ duk__update_lineinfo_currtoken(comp_ctx);
+
+ /*
+ * Function name (if any)
+ *
+ * We don't check for prohibited names here, because we don't
+ * yet know whether the function will be strict. Function body
+ * parsing handles this retroactively.
+ *
+ * For function expressions and declarations function name must
+ * be an Identifer (excludes reserved words). For setter/getter
+ * it is a PropertyName which allows reserved words and also
+ * strings and numbers (e.g. "{ get 1() { ... } }").
+ */
+
+ if (is_setget) {
+ /* PropertyName -> IdentifierName | StringLiteral | NumericLiteral */
+ if (comp_ctx->curr_token.t_nores == DUK_TOK_IDENTIFIER ||
+ comp_ctx->curr_token.t == DUK_TOK_STRING) {
+ duk_push_hstring(ctx, comp_ctx->curr_token.str1); /* keep in valstack */
+ } else if (comp_ctx->curr_token.t == DUK_TOK_NUMBER) {
+ duk_push_number(ctx, comp_ctx->curr_token.num);
+ duk_to_string(ctx, -1);
+ } else {
+ DUK_ERROR_SYNTAX(thr, DUK_STR_INVALID_GETSET_NAME);
+ }
+ comp_ctx->curr_func.h_name = duk_get_hstring(ctx, -1); /* borrowed reference */
+ DUK_ASSERT(comp_ctx->curr_func.h_name != NULL);
+ duk__advance(comp_ctx);
+ } else {
+ /* Function name is an Identifier (not IdentifierName), but we get
+ * the raw name (not recognizing keywords) here and perform the name
+ * checks only after pass 1.
+ */
+ if (comp_ctx->curr_token.t_nores == DUK_TOK_IDENTIFIER) {
+ duk_push_hstring(ctx, comp_ctx->curr_token.str1); /* keep in valstack */
+ comp_ctx->curr_func.h_name = duk_get_hstring(ctx, -1); /* borrowed reference */
+ DUK_ASSERT(comp_ctx->curr_func.h_name != NULL);
+ duk__advance(comp_ctx);
+ } else {
+ /* valstack will be unbalanced, which is OK */
+ DUK_ASSERT(!is_setget);
+ if (is_decl) {
+ DUK_ERROR_SYNTAX(thr, DUK_STR_FUNC_NAME_REQUIRED);
+ }
+ }
+ }
+
+ DUK_DDD(DUK_DDDPRINT("function name: %!O",
+ (duk_heaphdr *) comp_ctx->curr_func.h_name));
+
+ /*
+ * Formal argument list
+ *
+ * We don't check for prohibited names or for duplicate argument
+ * names here, becase we don't yet know whether the function will
+ * be strict. Function body parsing handles this retroactively.
+ */
+
+ duk__advance_expect(comp_ctx, DUK_TOK_LPAREN);
+
+ duk__parse_func_formals(comp_ctx);
+
+ DUK_ASSERT(comp_ctx->curr_token.t == DUK_TOK_RPAREN);
+ duk__advance(comp_ctx);
+
+ /*
+ * Parse function body
+ */
+
+ duk__parse_func_body(comp_ctx,
+ 0, /* expect_eof */
+ 0, /* implicit_return_value */
+ DUK_TOK_LCURLY); /* expect_token */
+
+ /*
+ * Convert duk_compiler_func to a function template and add it
+ * to the parent function table.
+ */
+
+ duk__convert_to_func_template(comp_ctx, is_setget /*force_no_namebind*/); /* -> [ ... func ] */
+}
+
+/* Parse an inner function, adding the function template to the current function's
+ * function table. Return a function number to be used by the outer function.
+ *
+ * Avoiding O(depth^2) inner function parsing is handled here. On the first pass,
+ * compile and register the function normally into the 'funcs' array, also recording
+ * a lexer point (offset/line) to the closing brace of the function. On the second
+ * pass, skip the function and return the same 'fnum' as on the first pass by using
+ * a running counter.
+ *
+ * An unfortunate side effect of this is that when parsing the inner function, almost
+ * nothing is known of the outer function, i.e. the inner function's scope. We don't
+ * need that information at the moment, but it would allow some optimizations if it
+ * were used.
+ */
+DUK_LOCAL duk_int_t duk__parse_func_like_fnum(duk_compiler_ctx *comp_ctx, duk_bool_t is_decl, duk_bool_t is_setget) {
+ duk_hthread *thr = comp_ctx->thr;
+ duk_context *ctx = (duk_context *) thr;
+ duk_compiler_func old_func;
+ duk_idx_t entry_top;
+ duk_int_t fnum;
+
+ /*
+ * On second pass, skip the function.
+ */
+
+ if (!comp_ctx->curr_func.in_scanning) {
+ duk_lexer_point lex_pt;
+
+ fnum = comp_ctx->curr_func.fnum_next++;
+ duk_get_prop_index(ctx, comp_ctx->curr_func.funcs_idx, (duk_uarridx_t) (fnum * 3 + 1));
+ lex_pt.offset = duk_to_int(ctx, -1);
+ duk_pop(ctx);
+ duk_get_prop_index(ctx, comp_ctx->curr_func.funcs_idx, (duk_uarridx_t) (fnum * 3 + 2));
+ lex_pt.line = duk_to_int(ctx, -1);
+ duk_pop(ctx);
+
+ DUK_DDD(DUK_DDDPRINT("second pass of an inner func, skip the function, reparse closing brace; lex offset=%ld, line=%ld",
+ (long) lex_pt.offset, (long) lex_pt.line));
+
+ DUK_LEXER_SETPOINT(&comp_ctx->lex, &lex_pt);
+ comp_ctx->curr_token.t = 0; /* this is needed for regexp mode */
+ comp_ctx->curr_token.start_line = 0; /* needed for line number tracking (becomes prev_token.start_line) */
+ duk__advance(comp_ctx);
+ duk__advance_expect(comp_ctx, DUK_TOK_RCURLY);
+
+ return fnum;
+ }
+
+ /*
+ * On first pass, perform actual parsing. Remember valstack top on entry
+ * to restore it later, and switch to using a new function in comp_ctx.
+ */
+
+ entry_top = duk_get_top(ctx);
+ DUK_DDD(DUK_DDDPRINT("before func: entry_top=%ld, curr_tok.start_offset=%ld",
+ (long) entry_top, (long) comp_ctx->curr_token.start_offset));
+
+ DUK_MEMCPY(&old_func, &comp_ctx->curr_func, sizeof(duk_compiler_func));
+
+ DUK_MEMZERO(&comp_ctx->curr_func, sizeof(duk_compiler_func));
+ duk__init_func_valstack_slots(comp_ctx);
+ DUK_ASSERT(comp_ctx->curr_func.num_formals == 0);
+
+ /* inherit initial strictness from parent */
+ comp_ctx->curr_func.is_strict = old_func.is_strict;
+
+ DUK_ASSERT(comp_ctx->curr_func.is_notail == 0);
+ comp_ctx->curr_func.is_function = 1;
+ DUK_ASSERT(comp_ctx->curr_func.is_eval == 0);
+ DUK_ASSERT(comp_ctx->curr_func.is_global == 0);
+ comp_ctx->curr_func.is_setget = is_setget;
+ comp_ctx->curr_func.is_decl = is_decl;
+
+ /*
+ * Parse inner function
+ */
+
+ duk__parse_func_like_raw(comp_ctx, is_decl, is_setget); /* pushes function template */
+
+ /* prev_token.start_offset points to the closing brace here; when skipping
+ * we're going to reparse the closing brace to ensure semicolon insertion
+ * etc work as expected.
+ */
+ DUK_DDD(DUK_DDDPRINT("after func: prev_tok.start_offset=%ld, curr_tok.start_offset=%ld",
+ (long) comp_ctx->prev_token.start_offset, (long) comp_ctx->curr_token.start_offset));
+ DUK_ASSERT(comp_ctx->lex.input[comp_ctx->prev_token.start_offset] == (duk_uint8_t) DUK_ASC_RCURLY);
+
+ /* XXX: append primitive */
+ DUK_ASSERT(duk_get_length(ctx, old_func.funcs_idx) == (duk_size_t) (old_func.fnum_next * 3));
+ fnum = old_func.fnum_next++;
+
+ if (fnum > DUK__MAX_FUNCS) {
+ DUK_ERROR_RANGE(comp_ctx->thr, DUK_STR_FUNC_LIMIT);
+ }
+
+ /* array writes autoincrement length */
+ (void) duk_put_prop_index(ctx, old_func.funcs_idx, (duk_uarridx_t) (fnum * 3));
+ duk_push_size_t(ctx, comp_ctx->prev_token.start_offset);
+ (void) duk_put_prop_index(ctx, old_func.funcs_idx, (duk_uarridx_t) (fnum * 3 + 1));
+ duk_push_int(ctx, comp_ctx->prev_token.start_line);
+ (void) duk_put_prop_index(ctx, old_func.funcs_idx, (duk_uarridx_t) (fnum * 3 + 2));
+
+ /*
+ * Cleanup: restore original function, restore valstack state.
+ */
+
+ DUK_MEMCPY((void *) &comp_ctx->curr_func, (void *) &old_func, sizeof(duk_compiler_func));
+ duk_set_top(ctx, entry_top);
+
+ DUK_ASSERT_TOP(ctx, entry_top);
+
+ return fnum;
+}
+
+/*
+ * Compile input string into an executable function template without
+ * arguments.
+ *
+ * The string is parsed as the "Program" production of Ecmascript E5.
+ * Compilation context can be either global code or eval code (see E5
+ * Sections 14 and 15.1.2.1).
+ *
+ * Input stack: [ ... filename ]
+ * Output stack: [ ... func_template ]
+ */
+
+/* XXX: source code property */
+
+DUK_LOCAL duk_ret_t duk__js_compile_raw(duk_context *ctx) {
+ duk_hthread *thr = (duk_hthread *) ctx;
+ duk_hstring *h_filename;
+ duk__compiler_stkstate *comp_stk;
+ duk_compiler_ctx *comp_ctx;
+ duk_lexer_point *lex_pt;
+ duk_compiler_func *func;
+ duk_idx_t entry_top;
+ duk_bool_t is_strict;
+ duk_bool_t is_eval;
+ duk_bool_t is_funcexpr;
+ duk_small_uint_t flags;
+
+ DUK_ASSERT(thr != NULL);
+
+ /*
+ * Arguments check
+ */
+
+ entry_top = duk_get_top(ctx);
+ DUK_ASSERT(entry_top >= 2);
+
+ comp_stk = (duk__compiler_stkstate *) duk_require_pointer(ctx, -1);
+ comp_ctx = &comp_stk->comp_ctx_alloc;
+ lex_pt = &comp_stk->lex_pt_alloc;
+ DUK_ASSERT(comp_ctx != NULL);
+ DUK_ASSERT(lex_pt != NULL);
+
+ flags = comp_stk->flags;
+ is_eval = (flags & DUK_JS_COMPILE_FLAG_EVAL ? 1 : 0);
+ is_strict = (flags & DUK_JS_COMPILE_FLAG_STRICT ? 1 : 0);
+ is_funcexpr = (flags & DUK_JS_COMPILE_FLAG_FUNCEXPR ? 1 : 0);
+
+ h_filename = duk_get_hstring(ctx, -2); /* may be undefined */
+
+ /*
+ * Init compiler and lexer contexts
+ */
+
+ func = &comp_ctx->curr_func;
+#ifdef DUK_USE_EXPLICIT_NULL_INIT
+ comp_ctx->thr = NULL;
+ comp_ctx->h_filename = NULL;
+ comp_ctx->prev_token.str1 = NULL;
+ comp_ctx->prev_token.str2 = NULL;
+ comp_ctx->curr_token.str1 = NULL;
+ comp_ctx->curr_token.str2 = NULL;
+#endif
+
+ duk_require_stack(ctx, DUK__COMPILE_ENTRY_SLOTS);
+
+ duk_push_dynamic_buffer(ctx, 0); /* entry_top + 0 */
+ duk_push_undefined(ctx); /* entry_top + 1 */
+ duk_push_undefined(ctx); /* entry_top + 2 */
+ duk_push_undefined(ctx); /* entry_top + 3 */
+ duk_push_undefined(ctx); /* entry_top + 4 */
+
+ comp_ctx->thr = thr;
+ comp_ctx->h_filename = h_filename;
+ comp_ctx->tok11_idx = entry_top + 1;
+ comp_ctx->tok12_idx = entry_top + 2;
+ comp_ctx->tok21_idx = entry_top + 3;
+ comp_ctx->tok22_idx = entry_top + 4;
+ comp_ctx->recursion_limit = DUK_USE_COMPILER_RECLIMIT;
+
+ /* comp_ctx->lex has been pre-initialized by caller: it has been
+ * zeroed and input/input_length has been set.
+ */
+ comp_ctx->lex.thr = thr;
+ /* comp_ctx->lex.input and comp_ctx->lex.input_length filled by caller */
+ comp_ctx->lex.slot1_idx = comp_ctx->tok11_idx;
+ comp_ctx->lex.slot2_idx = comp_ctx->tok12_idx;
+ comp_ctx->lex.buf_idx = entry_top + 0;
+ comp_ctx->lex.buf = (duk_hbuffer_dynamic *) duk_get_hbuffer(ctx, entry_top + 0);
+ DUK_ASSERT(comp_ctx->lex.buf != NULL);
+ DUK_ASSERT(DUK_HBUFFER_HAS_DYNAMIC(comp_ctx->lex.buf) && !DUK_HBUFFER_HAS_EXTERNAL(comp_ctx->lex.buf));
+ comp_ctx->lex.token_limit = DUK_COMPILER_TOKEN_LIMIT;
+
+ lex_pt->offset = 0;
+ lex_pt->line = 1;
+ DUK_LEXER_SETPOINT(&comp_ctx->lex, lex_pt); /* fills window */
+ comp_ctx->curr_token.start_line = 0; /* needed for line number tracking (becomes prev_token.start_line) */
+
+ /*
+ * Initialize function state for a zero-argument function
+ */
+
+ duk__init_func_valstack_slots(comp_ctx);
+ DUK_ASSERT(func->num_formals == 0);
+
+ if (is_funcexpr) {
+ /* Name will be filled from function expression, not by caller.
+ * This case is used by Function constructor and duk_compile()
+ * API with the DUK_COMPILE_FUNCTION option.
+ */
+ DUK_ASSERT(func->h_name == NULL);
+ } else {
+ duk_push_hstring_stridx(ctx, (is_eval ? DUK_STRIDX_EVAL :
+ DUK_STRIDX_GLOBAL));
+ func->h_name = duk_get_hstring(ctx, -1);
+ }
+
+ /*
+ * Parse a function body or a function-like expression, depending
+ * on flags.
+ */
+
+ func->is_strict = is_strict;
+ func->is_setget = 0;
+ func->is_decl = 0;
+
+ if (is_funcexpr) {
+ func->is_function = 1;
+ func->is_eval = 0;
+ func->is_global = 0;
+
+ duk__advance(comp_ctx); /* init 'curr_token' */
+ duk__advance_expect(comp_ctx, DUK_TOK_FUNCTION);
+ (void) duk__parse_func_like_raw(comp_ctx,
+ 0, /* is_decl */
+ 0); /* is_setget */
+ } else {
+ func->is_function = 0;
+ func->is_eval = is_eval;
+ func->is_global = !is_eval;
+
+ duk__parse_func_body(comp_ctx,
+ 1, /* expect_eof */
+ 1, /* implicit_return_value */
+ -1); /* expect_token */
+ }
+
+ /*
+ * Convert duk_compiler_func to a function template
+ */
+
+ duk__convert_to_func_template(comp_ctx, 0 /*force_no_namebind*/);
+
+ /*
+ * Wrapping duk_safe_call() will mangle the stack, just return stack top
+ */
+
+ /* [ ... filename (temps) func ] */
+
+ return 1;
+}
+
+DUK_INTERNAL void duk_js_compile(duk_hthread *thr, const duk_uint8_t *src_buffer, duk_size_t src_length, duk_small_uint_t flags) {
+ duk_context *ctx = (duk_context *) thr;
+ duk__compiler_stkstate comp_stk;
+ duk_compiler_ctx *prev_ctx;
+ duk_ret_t safe_rc;
+
+ /* XXX: this illustrates that a C catchpoint implemented using duk_safe_call()
+ * is a bit heavy at the moment. The wrapper compiles to ~180 bytes on x64.
+ * Alternatives would be nice.
+ */
+
+ DUK_ASSERT(thr != NULL);
+ DUK_ASSERT(src_buffer != NULL);
+
+ /* preinitialize lexer state partially */
+ DUK_MEMZERO(&comp_stk, sizeof(comp_stk));
+ comp_stk.flags = flags;
+ DUK_LEXER_INITCTX(&comp_stk.comp_ctx_alloc.lex);
+ comp_stk.comp_ctx_alloc.lex.input = src_buffer;
+ comp_stk.comp_ctx_alloc.lex.input_length = src_length;
+
+ duk_push_pointer(ctx, (void *) &comp_stk);
+
+ /* [ ... filename &comp_stk ] */
+
+ prev_ctx = thr->compile_ctx;
+ thr->compile_ctx = &comp_stk.comp_ctx_alloc; /* for duk_error_augment.c */
+ safe_rc = duk_safe_call(ctx, duk__js_compile_raw, 2 /*nargs*/, 1 /*nret*/);
+ thr->compile_ctx = prev_ctx; /* must restore reliably before returning */
+
+ if (safe_rc != DUK_EXEC_SUCCESS) {
+ duk_throw(ctx);
+ }
+
+ /* [ ... template ] */
+}
projects / ceph.git / blobdiff