]> git.proxmox.com Git - qemu.git/blobdiff - tcg/optimize.c
smc91c111: Fix receive starvation
[qemu.git] / tcg / optimize.c
index 9109b813e07efa5d839784faa053ac9f981f857d..89e2d6a3b3ff06275331e502a87b0ed644ad4d47 100644 (file)
@@ -46,6 +46,7 @@ struct tcg_temp_info {
     uint16_t prev_copy;
     uint16_t next_copy;
     tcg_target_ulong val;
+    tcg_target_ulong mask;
 };
 
 static struct tcg_temp_info temps[TCG_MAX_TEMPS];
@@ -63,6 +64,17 @@ static void reset_temp(TCGArg temp)
         }
     }
     temps[temp].state = TCG_TEMP_UNDEF;
+    temps[temp].mask = -1;
+}
+
+/* Reset all temporaries, given that there are NB_TEMPS of them.  */
+static void reset_all_temps(int nb_temps)
+{
+    int i;
+    for (i = 0; i < nb_temps; i++) {
+        temps[i].state = TCG_TEMP_UNDEF;
+        temps[i].mask = -1;
+    }
 }
 
 static int op_bits(TCGOpcode op)
@@ -139,33 +151,35 @@ static bool temps_are_copies(TCGArg arg1, TCGArg arg2)
 static void tcg_opt_gen_mov(TCGContext *s, TCGArg *gen_args,
                             TCGArg dst, TCGArg src)
 {
-        reset_temp(dst);
-        assert(temps[src].state != TCG_TEMP_CONST);
-
-        if (s->temps[src].type == s->temps[dst].type) {
-            if (temps[src].state != TCG_TEMP_COPY) {
-                temps[src].state = TCG_TEMP_COPY;
-                temps[src].next_copy = src;
-                temps[src].prev_copy = src;
-            }
-            temps[dst].state = TCG_TEMP_COPY;
-            temps[dst].next_copy = temps[src].next_copy;
-            temps[dst].prev_copy = src;
-            temps[temps[dst].next_copy].prev_copy = dst;
-            temps[src].next_copy = dst;
+    reset_temp(dst);
+    temps[dst].mask = temps[src].mask;
+    assert(temps[src].state != TCG_TEMP_CONST);
+
+    if (s->temps[src].type == s->temps[dst].type) {
+        if (temps[src].state != TCG_TEMP_COPY) {
+            temps[src].state = TCG_TEMP_COPY;
+            temps[src].next_copy = src;
+            temps[src].prev_copy = src;
         }
+        temps[dst].state = TCG_TEMP_COPY;
+        temps[dst].next_copy = temps[src].next_copy;
+        temps[dst].prev_copy = src;
+        temps[temps[dst].next_copy].prev_copy = dst;
+        temps[src].next_copy = dst;
+    }
 
-        gen_args[0] = dst;
-        gen_args[1] = src;
+    gen_args[0] = dst;
+    gen_args[1] = src;
 }
 
 static void tcg_opt_gen_movi(TCGArg *gen_args, TCGArg dst, TCGArg val)
 {
-        reset_temp(dst);
-        temps[dst].state = TCG_TEMP_CONST;
-        temps[dst].val = val;
-        gen_args[0] = dst;
-        gen_args[1] = val;
+    reset_temp(dst);
+    temps[dst].state = TCG_TEMP_CONST;
+    temps[dst].val = val;
+    temps[dst].mask = val;
+    gen_args[0] = dst;
+    gen_args[1] = val;
 }
 
 static TCGOpcode op_to_mov(TCGOpcode op)
@@ -184,6 +198,8 @@ static TCGOpcode op_to_mov(TCGOpcode op)
 
 static TCGArg do_constant_folding_2(TCGOpcode op, TCGArg x, TCGArg y)
 {
+    uint64_t l64, h64;
+
     switch (op) {
     CASE_OP_32_64(add):
         return x + y;
@@ -222,20 +238,16 @@ static TCGArg do_constant_folding_2(TCGOpcode op, TCGArg x, TCGArg y)
         return (int64_t)x >> (int64_t)y;
 
     case INDEX_op_rotr_i32:
-        x = ((uint32_t)x << (32 - y)) | ((uint32_t)x >> y);
-        return x;
+        return ror32(x, y);
 
     case INDEX_op_rotr_i64:
-        x = ((uint64_t)x << (64 - y)) | ((uint64_t)x >> y);
-        return x;
+        return ror64(x, y);
 
     case INDEX_op_rotl_i32:
-        x = ((uint32_t)x << y) | ((uint32_t)x >> (32 - y));
-        return x;
+        return rol32(x, y);
 
     case INDEX_op_rotl_i64:
-        x = ((uint64_t)x << y) | ((uint64_t)x >> (64 - y));
-        return x;
+        return rol64(x, y);
 
     CASE_OP_32_64(not):
         return ~x;
@@ -276,6 +288,37 @@ static TCGArg do_constant_folding_2(TCGOpcode op, TCGArg x, TCGArg y)
     case INDEX_op_ext32u_i64:
         return (uint32_t)x;
 
+    case INDEX_op_muluh_i32:
+        return ((uint64_t)(uint32_t)x * (uint32_t)y) >> 32;
+    case INDEX_op_mulsh_i32:
+        return ((int64_t)(int32_t)x * (int32_t)y) >> 32;
+
+    case INDEX_op_muluh_i64:
+        mulu64(&l64, &h64, x, y);
+        return h64;
+    case INDEX_op_mulsh_i64:
+        muls64(&l64, &h64, x, y);
+        return h64;
+
+    case INDEX_op_div_i32:
+        /* Avoid crashing on divide by zero, otherwise undefined.  */
+        return (int32_t)x / ((int32_t)y ? : 1);
+    case INDEX_op_divu_i32:
+        return (uint32_t)x / ((uint32_t)y ? : 1);
+    case INDEX_op_div_i64:
+        return (int64_t)x / ((int64_t)y ? : 1);
+    case INDEX_op_divu_i64:
+        return (uint64_t)x / ((uint64_t)y ? : 1);
+
+    case INDEX_op_rem_i32:
+        return (int32_t)x % ((int32_t)y ? : 1);
+    case INDEX_op_remu_i32:
+        return (uint32_t)x % ((uint32_t)y ? : 1);
+    case INDEX_op_rem_i64:
+        return (int64_t)x % ((int64_t)y ? : 1);
+    case INDEX_op_remu_i64:
+        return (uint64_t)x % ((uint64_t)y ? : 1);
+
     default:
         fprintf(stderr,
                 "Unrecognized operation %d in do_constant_folding.\n", op);
@@ -470,6 +513,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
                                     TCGArg *args, TCGOpDef *tcg_op_defs)
 {
     int i, nb_ops, op_index, nb_temps, nb_globals, nb_call_args;
+    tcg_target_ulong mask, affected;
     TCGOpcode op;
     const TCGOpDef *def;
     TCGArg *gen_args;
@@ -482,7 +526,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
 
     nb_temps = s->nb_temps;
     nb_globals = s->nb_globals;
-    memset(temps, 0, nb_temps * sizeof(struct tcg_temp_info));
+    reset_all_temps(nb_temps);
 
     nb_ops = tcg_opc_ptr - s->gen_opc_buf;
     gen_args = args;
@@ -516,6 +560,8 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
         CASE_OP_32_64(eqv):
         CASE_OP_32_64(nand):
         CASE_OP_32_64(nor):
+        CASE_OP_32_64(muluh):
+        CASE_OP_32_64(mulsh):
             swap_commutative(args[0], &args[1], &args[2]);
             break;
         CASE_OP_32_64(brcond):
@@ -539,11 +585,12 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
                 args[5] = tcg_invert_cond(args[5]);
             }
             break;
-        case INDEX_op_add2_i32:
+        CASE_OP_32_64(add2):
             swap_commutative(args[0], &args[2], &args[4]);
             swap_commutative(args[1], &args[3], &args[5]);
             break;
-        case INDEX_op_mulu2_i32:
+        CASE_OP_32_64(mulu2):
+        CASE_OP_32_64(muls2):
             swap_commutative(args[0], &args[2], &args[3]);
             break;
         case INDEX_op_brcond2_i32:
@@ -560,7 +607,8 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
             break;
         }
 
-        /* Simplify expressions for "shift/rot r, 0, a => movi r, 0" */
+        /* Simplify expressions for "shift/rot r, 0, a => movi r, 0",
+           and "sub r, 0, a => neg r, a" case.  */
         switch (op) {
         CASE_OP_32_64(shl):
         CASE_OP_32_64(shr):
@@ -576,6 +624,37 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
                 continue;
             }
             break;
+        CASE_OP_32_64(sub):
+            {
+                TCGOpcode neg_op;
+                bool have_neg;
+
+                if (temps[args[2]].state == TCG_TEMP_CONST) {
+                    /* Proceed with possible constant folding. */
+                    break;
+                }
+                if (op == INDEX_op_sub_i32) {
+                    neg_op = INDEX_op_neg_i32;
+                    have_neg = TCG_TARGET_HAS_neg_i32;
+                } else {
+                    neg_op = INDEX_op_neg_i64;
+                    have_neg = TCG_TARGET_HAS_neg_i64;
+                }
+                if (!have_neg) {
+                    break;
+                }
+                if (temps[args[1]].state == TCG_TEMP_CONST
+                    && temps[args[1]].val == 0) {
+                    s->gen_opc_buf[op_index] = neg_op;
+                    reset_temp(args[0]);
+                    gen_args[0] = args[0];
+                    gen_args[1] = args[2];
+                    args += 3;
+                    gen_args += 2;
+                    continue;
+                }
+            }
+            break;
         default:
             break;
         }
@@ -612,10 +691,119 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
             break;
         }
 
+        /* Simplify using known-zero bits */
+        mask = -1;
+        affected = -1;
+        switch (op) {
+        CASE_OP_32_64(ext8s):
+            if ((temps[args[1]].mask & 0x80) != 0) {
+                break;
+            }
+        CASE_OP_32_64(ext8u):
+            mask = 0xff;
+            goto and_const;
+        CASE_OP_32_64(ext16s):
+            if ((temps[args[1]].mask & 0x8000) != 0) {
+                break;
+            }
+        CASE_OP_32_64(ext16u):
+            mask = 0xffff;
+            goto and_const;
+        case INDEX_op_ext32s_i64:
+            if ((temps[args[1]].mask & 0x80000000) != 0) {
+                break;
+            }
+        case INDEX_op_ext32u_i64:
+            mask = 0xffffffffU;
+            goto and_const;
+
+        CASE_OP_32_64(and):
+            mask = temps[args[2]].mask;
+            if (temps[args[2]].state == TCG_TEMP_CONST) {
+        and_const:
+                affected = temps[args[1]].mask & ~mask;
+            }
+            mask = temps[args[1]].mask & mask;
+            break;
+
+        CASE_OP_32_64(sar):
+            if (temps[args[2]].state == TCG_TEMP_CONST) {
+                mask = ((tcg_target_long)temps[args[1]].mask
+                        >> temps[args[2]].val);
+            }
+            break;
+
+        CASE_OP_32_64(shr):
+            if (temps[args[2]].state == TCG_TEMP_CONST) {
+                mask = temps[args[1]].mask >> temps[args[2]].val;
+            }
+            break;
+
+        CASE_OP_32_64(shl):
+            if (temps[args[2]].state == TCG_TEMP_CONST) {
+                mask = temps[args[1]].mask << temps[args[2]].val;
+            }
+            break;
+
+        CASE_OP_32_64(neg):
+            /* Set to 1 all bits to the left of the rightmost.  */
+            mask = -(temps[args[1]].mask & -temps[args[1]].mask);
+            break;
+
+        CASE_OP_32_64(deposit):
+            tmp = ((1ull << args[4]) - 1);
+            mask = ((temps[args[1]].mask & ~(tmp << args[3]))
+                    | ((temps[args[2]].mask & tmp) << args[3]));
+            break;
+
+        CASE_OP_32_64(or):
+        CASE_OP_32_64(xor):
+            mask = temps[args[1]].mask | temps[args[2]].mask;
+            break;
+
+        CASE_OP_32_64(setcond):
+            mask = 1;
+            break;
+
+        CASE_OP_32_64(movcond):
+            mask = temps[args[3]].mask | temps[args[4]].mask;
+            break;
+
+        default:
+            break;
+        }
+
+        if (mask == 0) {
+            assert(def->nb_oargs == 1);
+            s->gen_opc_buf[op_index] = op_to_movi(op);
+            tcg_opt_gen_movi(gen_args, args[0], 0);
+            args += def->nb_oargs + def->nb_iargs + def->nb_cargs;
+            gen_args += 2;
+            continue;
+        }
+        if (affected == 0) {
+            assert(def->nb_oargs == 1);
+            if (temps_are_copies(args[0], args[1])) {
+                s->gen_opc_buf[op_index] = INDEX_op_nop;
+            } else if (temps[args[1]].state != TCG_TEMP_CONST) {
+                s->gen_opc_buf[op_index] = op_to_mov(op);
+                tcg_opt_gen_mov(s, gen_args, args[0], args[1]);
+                gen_args += 2;
+            } else {
+                s->gen_opc_buf[op_index] = op_to_movi(op);
+                tcg_opt_gen_movi(gen_args, args[0], temps[args[1]].val);
+                gen_args += 2;
+            }
+            args += def->nb_iargs + 1;
+            continue;
+        }
+
         /* Simplify expression for "op r, a, 0 => movi r, 0" cases */
         switch (op) {
         CASE_OP_32_64(and):
         CASE_OP_32_64(mul):
+        CASE_OP_32_64(muluh):
+        CASE_OP_32_64(mulsh):
             if ((temps[args[2]].state == TCG_TEMP_CONST
                 && temps[args[2]].val == 0)) {
                 s->gen_opc_buf[op_index] = op_to_movi(op);
@@ -727,6 +915,12 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
         CASE_OP_32_64(eqv):
         CASE_OP_32_64(nand):
         CASE_OP_32_64(nor):
+        CASE_OP_32_64(muluh):
+        CASE_OP_32_64(mulsh):
+        CASE_OP_32_64(div):
+        CASE_OP_32_64(divu):
+        CASE_OP_32_64(rem):
+        CASE_OP_32_64(remu):
             if (temps[args[1]].state == TCG_TEMP_CONST
                 && temps[args[2]].state == TCG_TEMP_CONST) {
                 s->gen_opc_buf[op_index] = op_to_movi(op);
@@ -768,7 +962,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
             tmp = do_constant_folding_cond(op, args[0], args[1], args[2]);
             if (tmp != 2) {
                 if (tmp) {
-                    memset(temps, 0, nb_temps * sizeof(struct tcg_temp_info));
+                    reset_all_temps(nb_temps);
                     s->gen_opc_buf[op_index] = INDEX_op_br;
                     gen_args[0] = args[3];
                     gen_args += 1;
@@ -861,7 +1055,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
             tmp = do_constant_folding_cond2(&args[0], &args[2], args[4]);
             if (tmp != 2) {
                 if (tmp) {
-                    memset(temps, 0, nb_temps * sizeof(struct tcg_temp_info));
+                    reset_all_temps(nb_temps);
                     s->gen_opc_buf[op_index] = INDEX_op_br;
                     gen_args[0] = args[5];
                     gen_args += 1;
@@ -875,7 +1069,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
                        && temps[args[3]].val == 0) {
                 /* Simplify LT/GE comparisons vs zero to a single compare
                    vs the high word of the input.  */
-                memset(temps, 0, nb_temps * sizeof(struct tcg_temp_info));
+                reset_all_temps(nb_temps);
                 s->gen_opc_buf[op_index] = INDEX_op_brcond_i32;
                 gen_args[0] = args[1];
                 gen_args[1] = args[3];
@@ -902,6 +1096,7 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
                 /* Simplify LT/GE comparisons vs zero to a single compare
                    vs the high word of the input.  */
                 s->gen_opc_buf[op_index] = INDEX_op_setcond_i32;
+                reset_temp(args[0]);
                 gen_args[0] = args[0];
                 gen_args[1] = args[2];
                 gen_args[2] = args[4];
@@ -938,9 +1133,10 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
             /* Default case: we know nothing about operation (or were unable
                to compute the operation result) so no propagation is done.
                We trash everything if the operation is the end of a basic
-               block, otherwise we only trash the output args.  */
+               block, otherwise we only trash the output args.  "mask" is
+               the non-zero bits mask for the first output arg.  */
             if (def->flags & TCG_OPF_BB_END) {
-                memset(temps, 0, nb_temps * sizeof(struct tcg_temp_info));
+                reset_all_temps(nb_temps);
             } else {
                 for (i = 0; i < def->nb_oargs; i++) {
                     reset_temp(args[i]);