target-i386: emulate LOCK'ed INC using atomic helper

[rth: Merge gen_inc_locked back into gen_inc to share cc update.]

Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1467054136-10430-14-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 15:01:59 -04:00 committed by Richard Henderson
parent a7cee522f3
commit 60e573462f

View File

@ -1361,21 +1361,23 @@ static void gen_op(DisasContext *s1, int op, TCGMemOp ot, int d)
/* if d == OR_TMP0, it means memory operand (address in A0) */
static void gen_inc(DisasContext *s1, TCGMemOp ot, int d, int c)
{
if (d != OR_TMP0) {
gen_op_mov_v_reg(ot, cpu_T0, d);
if (s1->prefix & PREFIX_LOCK) {
tcg_gen_movi_tl(cpu_T0, c > 0 ? 1 : -1);
tcg_gen_atomic_add_fetch_tl(cpu_T0, cpu_A0, cpu_T0,
s1->mem_index, ot | MO_LE);
} else {
gen_op_ld_v(s1, ot, cpu_T0, cpu_A0);
if (d != OR_TMP0) {
gen_op_mov_v_reg(ot, cpu_T0, d);
} else {
gen_op_ld_v(s1, ot, cpu_T0, cpu_A0);
}
tcg_gen_addi_tl(cpu_T0, cpu_T0, (c > 0 ? 1 : -1));
gen_op_st_rm_T0_A0(s1, ot, d);
}
gen_compute_eflags_c(s1, cpu_cc_src);
if (c > 0) {
tcg_gen_addi_tl(cpu_T0, cpu_T0, 1);
set_cc_op(s1, CC_OP_INCB + ot);
} else {
tcg_gen_addi_tl(cpu_T0, cpu_T0, -1);
set_cc_op(s1, CC_OP_DECB + ot);
}
gen_op_st_rm_T0_A0(s1, ot, d);
tcg_gen_mov_tl(cpu_cc_dst, cpu_T0);
set_cc_op(s1, (c > 0 ? CC_OP_INCB : CC_OP_DECB) + ot);
}
static void gen_shift_flags(DisasContext *s, TCGMemOp ot, TCGv result,