target/m68k: Always return a temporary from gen_lea_mode

Returning a raw areg does not preserve the value if the areg
is subsequently modified.  Fixes, e.g. "jsr (sp)", where the
return address is pushed before the branch.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2483
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240813000737.228470-1-richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
This commit is contained in:
Richard Henderson 2024-08-13 10:04:00 +10:00
parent 3213da7b95
commit 352cc9f300

View File

@ -720,7 +720,9 @@ static TCGv gen_lea_mode(CPUM68KState *env, DisasContext *s,
}
/* fallthru */
case 2: /* Indirect register */
return get_areg(s, reg0);
tmp = tcg_temp_new();
tcg_gen_mov_i32(tmp, get_areg(s, reg0));
return tmp;
case 4: /* Indirect predecrememnt. */
if (opsize == OS_UNSIZED) {
return NULL_QREG;
@ -747,20 +749,23 @@ static TCGv gen_lea_mode(CPUM68KState *env, DisasContext *s,
switch (reg0) {
case 0: /* Absolute short. */
offset = (int16_t)read_im16(env, s);
return tcg_constant_i32(offset);
break;
case 1: /* Absolute long. */
offset = read_im32(env, s);
return tcg_constant_i32(offset);
break;
case 2: /* pc displacement */
offset = s->pc;
offset += (int16_t)read_im16(env, s);
return tcg_constant_i32(offset);
break;
case 3: /* pc index+displacement. */
return gen_lea_indexed(env, s, NULL_QREG);
case 4: /* Immediate. */
default:
return NULL_QREG;
}
tmp = tcg_temp_new();
tcg_gen_movi_i32(tmp, offset);
return tmp;
}
/* Should never happen. */
return NULL_QREG;