diff mbox

[v3,5/5] target-m68k: increment/decrement with SP

Message ID 1484332593-16782-6-git-send-email-laurent@vivier.eu (mailing list archive)
State New, archived
Headers show

Commit Message

Laurent Vivier Jan. 13, 2017, 6:36 p.m. UTC 
On 680x0 family only.

Address Register indirect With postincrement:

When using the stack pointer (A7) with byte size data, the register
is incremented by two.

Address Register indirect With predecrement:

When using the stack pointer (A7) with byte size data, the register
is decremented by two.

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Thomas Huth <huth@tuxfamily.org>
---
 target/m68k/translate.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

Comments

Richard Henderson Jan. 13, 2017, 8:08 p.m. UTC | #1 
On 01/13/2017 10:36 AM, Laurent Vivier wrote:
> On 680x0 family only.
> 
> Address Register indirect With postincrement:
> 
> When using the stack pointer (A7) with byte size data, the register
> is incremented by two.
> 
> Address Register indirect With predecrement:
> 
> When using the stack pointer (A7) with byte size data, the register
> is decremented by two.
> 
> Signed-off-by: Laurent Vivier <laurent@vivier.eu>
> Reviewed-by: Thomas Huth <huth@tuxfamily.org>
> ---
>  target/m68k/translate.c | 14 ++++++++++++--
>  1 file changed, 12 insertions(+), 2 deletions(-)

Reviewed-by: Richard Henderson <rth@twiddle.net>


r~
diff mbox

Patch

diff --git a/target/m68k/translate.c b/target/m68k/translate.c
index cf5d8dd..9f60fbc 100644
--- a/target/m68k/translate.c
+++ b/target/m68k/translate.c
@@ -725,7 +725,12 @@  static TCGv gen_lea_mode(CPUM68KState *env, DisasContext *s,
         }
         reg = get_areg(s, reg0);
         tmp = tcg_temp_new();
-        tcg_gen_subi_i32(tmp, reg, opsize_bytes(opsize));
+        if (reg0 == 7 && opsize == OS_BYTE &&
+            m68k_feature(s->env, M68K_FEATURE_M68000)) {
+            tcg_gen_subi_i32(tmp, reg, 2);
+        } else {
+            tcg_gen_subi_i32(tmp, reg, opsize_bytes(opsize));
+        }
         return tmp;
     case 5: /* Indirect displacement.  */
         reg = get_areg(s, reg0);
@@ -801,7 +806,12 @@  static TCGv gen_ea_mode(CPUM68KState *env, DisasContext *s, int mode, int reg0,
         result = gen_ldst(s, opsize, reg, val, what);
         if (what == EA_STORE || !addrp) {
             TCGv tmp = tcg_temp_new();
-            tcg_gen_addi_i32(tmp, reg, opsize_bytes(opsize));
+            if (reg0 == 7 && opsize == OS_BYTE &&
+                m68k_feature(s->env, M68K_FEATURE_M68000)) {
+                tcg_gen_addi_i32(tmp, reg, 2);
+            } else {
+                tcg_gen_addi_i32(tmp, reg, opsize_bytes(opsize));
+            }
             delay_set_areg(s, reg0, tmp, true);
         }
         return result;