mirrors/qemu
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

target-i386: emulate LOCK'ed BTX ops using atomic helpers

Browse Source 
[rth: Avoid redundant qemu_ld in locked case.  Fix previously unnoticed
incorrect zero-extension of address in register-offset case.]

Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1467054136-10430-18-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 15:02:03 -04:00 committed by Richard Henderson
parent f53b01817f
commit cfe819d309
1 changed files with 57 additions and 30 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

87
target-i386/translate.c
View File

@ -6655,7 +6655,9 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
if (mod != 3) {
s->rip_offset = 1;
gen_lea_modrm(env, s, modrm);
gen_op_ld_v(s, ot, cpu_T0, cpu_A0);
if (!(s->prefix & PREFIX_LOCK)) {
gen_op_ld_v(s, ot, cpu_T0, cpu_A0);
}
} else {
gen_op_mov_v_reg(ot, cpu_T0, rm);
}
@ -6685,44 +6687,69 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
rm = (modrm & 7) | REX_B(s);
gen_op_mov_v_reg(MO_32, cpu_T1, reg);
if (mod != 3) {
gen_lea_modrm(env, s, modrm);
AddressParts a = gen_lea_modrm_0(env, s, modrm);
/* specific case: we need to add a displacement */
gen_exts(ot, cpu_T1);
tcg_gen_sari_tl(cpu_tmp0, cpu_T1, 3 + ot);
tcg_gen_shli_tl(cpu_tmp0, cpu_tmp0, ot);
tcg_gen_add_tl(cpu_A0, cpu_A0, cpu_tmp0);
gen_op_ld_v(s, ot, cpu_T0, cpu_A0);
tcg_gen_add_tl(cpu_A0, gen_lea_modrm_1(a), cpu_tmp0);
gen_lea_v_seg(s, s->aflag, cpu_A0, a.def_seg, s->override);
if (!(s->prefix & PREFIX_LOCK)) {
gen_op_ld_v(s, ot, cpu_T0, cpu_A0);
}
} else {
gen_op_mov_v_reg(ot, cpu_T0, rm);
}
bt_op:
tcg_gen_andi_tl(cpu_T1, cpu_T1, (1 << (3 + ot)) - 1);
tcg_gen_shr_tl(cpu_tmp4, cpu_T0, cpu_T1);
switch(op) {
case 0:
break;
case 1:
tcg_gen_movi_tl(cpu_tmp0, 1);
tcg_gen_shl_tl(cpu_tmp0, cpu_tmp0, cpu_T1);
tcg_gen_or_tl(cpu_T0, cpu_T0, cpu_tmp0);
break;
case 2:
tcg_gen_movi_tl(cpu_tmp0, 1);
tcg_gen_shl_tl(cpu_tmp0, cpu_tmp0, cpu_T1);
tcg_gen_andc_tl(cpu_T0, cpu_T0, cpu_tmp0);
break;
default:
case 3:
tcg_gen_movi_tl(cpu_tmp0, 1);
tcg_gen_shl_tl(cpu_tmp0, cpu_tmp0, cpu_T1);
tcg_gen_xor_tl(cpu_T0, cpu_T0, cpu_tmp0);
break;
}
if (op != 0) {
if (mod != 3) {
gen_op_st_v(s, ot, cpu_T0, cpu_A0);
} else {
gen_op_mov_reg_v(ot, rm, cpu_T0);
tcg_gen_movi_tl(cpu_tmp0, 1);
tcg_gen_shl_tl(cpu_tmp0, cpu_tmp0, cpu_T1);
if (s->prefix & PREFIX_LOCK) {
switch (op) {
case 0: /* bt */
/* Needs no atomic ops; we surpressed the normal
memory load for LOCK above so do it now. */
gen_op_ld_v(s, ot, cpu_T0, cpu_A0);
break;
case 1: /* bts */
tcg_gen_atomic_fetch_or_tl(cpu_T0, cpu_A0, cpu_tmp0,
s->mem_index, ot | MO_LE);
break;
case 2: /* btr */
tcg_gen_not_tl(cpu_tmp0, cpu_tmp0);
tcg_gen_atomic_fetch_and_tl(cpu_T0, cpu_A0, cpu_tmp0,
s->mem_index, ot | MO_LE);
break;
default:
case 3: /* btc */
tcg_gen_atomic_fetch_xor_tl(cpu_T0, cpu_A0, cpu_tmp0,
s->mem_index, ot | MO_LE);
break;
}
tcg_gen_shr_tl(cpu_tmp4, cpu_T0, cpu_T1);
} else {
tcg_gen_shr_tl(cpu_tmp4, cpu_T0, cpu_T1);
switch (op) {
case 0: /* bt */
/* Data already loaded; nothing to do. */
break;
case 1: /* bts */
tcg_gen_or_tl(cpu_T0, cpu_T0, cpu_tmp0);
break;
case 2: /* btr */
tcg_gen_andc_tl(cpu_T0, cpu_T0, cpu_tmp0);
break;
default:
case 3: /* btc */
tcg_gen_xor_tl(cpu_T0, cpu_T0, cpu_tmp0);
break;
}
if (op != 0) {
if (mod != 3) {
gen_op_st_v(s, ot, cpu_T0, cpu_A0);
} else {
gen_op_mov_reg_v(ot, rm, cpu_T0);
}
}
}