target/m68k: introduce gen_singlestep_exception() function

Introduce a new gen_singlestep_exception() function to be called when generating
the EXCP_DEBUG exception in single-step mode rather than calling
gen_raise_exception(EXCP_DEBUG) directly. This allows for the single-step
exception behaviour for all callers to be managed in a single place.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210519142917.16693-4-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

diff --git a/target/m68k/translate.c b/target/m68k/translate.c
index f14ecab5a502aba2e63d91782784c36757930497..10e8aba42e421be279cb6910979065a5d2dadafd 100644 (file)
--- a/target/m68k/translate.c
+++ b/target/m68k/translate.c
@@ -319,6 +319,15 @@ static void gen_exception(DisasContext *s, uint32_t dest, int nr)
     s->base.is_jmp = DISAS_NORETURN;
 }
 
+static void gen_singlestep_exception(DisasContext *s)
+{
+    /*
+     * Generate the right kind of exception for singlestep, which is
+     * EXCP_DEBUG for QEMU's gdb singlestepping.
+     */
+    gen_raise_exception(EXCP_DEBUG);
+}
+
 static inline void gen_addr_fault(DisasContext *s)
 {
     gen_exception(s, s->base.pc_next, EXCP_ADDRESS);
@@ -1520,7 +1529,7 @@ static void gen_jmp_tb(DisasContext *s, int n, uint32_t dest)
     if (unlikely(is_singlestepping(s))) {
         update_cc_op(s);
         tcg_gen_movi_i32(QREG_PC, dest);
-        gen_raise_exception(EXCP_DEBUG);
+        gen_singlestep_exception(s);
     } else if (use_goto_tb(s, dest)) {
         tcg_gen_goto_tb(n);
         tcg_gen_movi_i32(QREG_PC, dest);
@@ -6260,7 +6269,7 @@ static void m68k_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
         update_cc_op(dc);
         if (is_singlestepping(dc)) {
             tcg_gen_movi_i32(QREG_PC, dc->pc);
-            gen_raise_exception(EXCP_DEBUG);
+            gen_singlestep_exception(dc);
         } else {
             gen_jmp_tb(dc, 0, dc->pc);
         }
@@ -6268,7 +6277,7 @@ static void m68k_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
     case DISAS_JUMP:
         /* We updated CC_OP and PC in gen_jmp/gen_jmp_im.  */
         if (is_singlestepping(dc)) {
-            gen_raise_exception(EXCP_DEBUG);
+            gen_singlestep_exception(dc);
         } else {
             tcg_gen_lookup_and_goto_ptr();
         }
@@ -6279,7 +6288,7 @@ static void m68k_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
          * other state that may require returning to the main loop.
          */
         if (is_singlestepping(dc)) {
-            gen_raise_exception(EXCP_DEBUG);
+            gen_singlestep_exception(dc);
         } else {
             tcg_gen_exit_tb(NULL, 0);
         }