target-i386: emulate LOCK'ed NOT using atomic helper

[rth: Avoid qemu_load that's redundant with the atomic op.]

Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1467054136-10430-15-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
This commit is contained in:
Emilio G. Cota 2016-06-27 15:02:00 -04:00 committed by Richard Henderson
parent 60e573462f
commit 2a5fe8ae14

View File

@ -4674,10 +4674,15 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
rm = (modrm & 7) | REX_B(s);
op = (modrm >> 3) & 7;
if (mod != 3) {
if (op == 0)
if (op == 0) {
s->rip_offset = insn_const_size(ot);
}
gen_lea_modrm(env, s, modrm);
gen_op_ld_v(s, ot, cpu_T0, cpu_A0);
/* For those below that handle locked memory, don't load here. */
if (!(s->prefix & PREFIX_LOCK)
|| op != 2) {
gen_op_ld_v(s, ot, cpu_T0, cpu_A0);
}
} else {
gen_op_mov_v_reg(ot, cpu_T0, rm);
}
@ -4690,11 +4695,20 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
set_cc_op(s, CC_OP_LOGICB + ot);
break;
case 2: /* not */
tcg_gen_not_tl(cpu_T0, cpu_T0);
if (mod != 3) {
gen_op_st_v(s, ot, cpu_T0, cpu_A0);
if (s->prefix & PREFIX_LOCK) {
if (mod == 3) {
goto illegal_op;
}
tcg_gen_movi_tl(cpu_T0, ~0);
tcg_gen_atomic_xor_fetch_tl(cpu_T0, cpu_A0, cpu_T0,
s->mem_index, ot | MO_LE);
} else {
gen_op_mov_reg_v(ot, rm, cpu_T0);
tcg_gen_not_tl(cpu_T0, cpu_T0);
if (mod != 3) {
gen_op_st_v(s, ot, cpu_T0, cpu_A0);
} else {
gen_op_mov_reg_v(ot, rm, cpu_T0);
}
}
break;
case 3: /* neg */