Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
target/i386/tcg/decode-new.h | 3 +
target/i386/tcg/translate.c | 147 +------------------------------
target/i386/tcg/decode-new.c.inc | 45 +++++++---
target/i386/tcg/emit.c.inc | 130 ++++++++++++++++++++++++++-
4 files changed, 166 insertions(+), 159 deletions(-)
diff --git a/target/i386/tcg/decode-new.h b/target/i386/tcg/decode-new.h
index c9f958bb0e5..f781bb5bbec 100644
--- a/target/i386/tcg/decode-new.h
+++ b/target/i386/tcg/decode-new.h
@@ -188,6 +188,9 @@ typedef enum X86InsnSpecial {
/* Always locked if it has a memory operand (XCHG) */
X86_SPECIAL_Locked,
+ /* Like HasLock, but also operand 2 provides bit displacement into memory. */
+ X86_SPECIAL_BitTest,
+
/* Do not load effective address in s->A0 */
X86_SPECIAL_NoLoadEA,
diff --git a/target/i386/tcg/translate.c b/target/i386/tcg/translate.c
index 4b2f7488022..c3843092350 100644
--- a/target/i386/tcg/translate.c
+++ b/target/i386/tcg/translate.c
@@ -729,11 +729,6 @@ static void gen_extu(MemOp ot, TCGv reg)
gen_ext_tl(reg, reg, ot, false);
}
-static void gen_exts(MemOp ot, TCGv reg)
-{
- gen_ext_tl(reg, reg, ot, true);
-}
-
static void gen_op_j_ecx(DisasContext *s, TCGCond cond, TCGLabel *label1)
{
TCGv tmp = gen_ext_tl(NULL, cpu_regs[R_ECX], s->aflag, false);
@@ -3078,7 +3073,7 @@ static void disas_insn_old(DisasContext *s, CPUState *cpu, int b)
MemOp dflag = s->dflag;
int shift;
MemOp ot;
- int modrm, reg, rm, mod, op, opreg, val;
+ int modrm, reg, rm, mod, op, opreg;
/* now check op code */
switch (b) {
@@ -3278,146 +3273,6 @@ static void disas_insn_old(DisasContext *s, CPUState *cpu, int b)
gen_shiftd_rm_T1(s, ot, opreg, op, cpu_regs[R_ECX]);
}
break;
-
- /************************/
- /* bit operations */
- case 0x1ba: /* bt/bts/btr/btc Gv, im */
- ot = dflag;
- modrm = x86_ldub_code(env, s);
- op = (modrm >> 3) & 7;
- mod = (modrm >> 6) & 3;
- rm = (modrm & 7) | REX_B(s);
- if (mod != 3) {
- s->rip_offset = 1;
- gen_lea_modrm(env, s, modrm);
- if (!(s->prefix & PREFIX_LOCK)) {
- gen_op_ld_v(s, ot, s->T0, s->A0);
- }
- } else {
- gen_op_mov_v_reg(s, ot, s->T0, rm);
- }
- /* load shift */
- val = x86_ldub_code(env, s);
- tcg_gen_movi_tl(s->T1, val);
- if (op < 4)
- goto unknown_op;
- op -= 4;
- goto bt_op;
- case 0x1a3: /* bt Gv, Ev */
- op = 0;
- goto do_btx;
- case 0x1ab: /* bts */
- op = 1;
- goto do_btx;
- case 0x1b3: /* btr */
- op = 2;
- goto do_btx;
- case 0x1bb: /* btc */
- op = 3;
- do_btx:
- ot = dflag;
- modrm = x86_ldub_code(env, s);
- reg = ((modrm >> 3) & 7) | REX_R(s);
- mod = (modrm >> 6) & 3;
- rm = (modrm & 7) | REX_B(s);
- gen_op_mov_v_reg(s, MO_32, s->T1, reg);
- if (mod != 3) {
- AddressParts a = gen_lea_modrm_0(env, s, modrm);
- /* specific case: we need to add a displacement */
- gen_exts(ot, s->T1);
- tcg_gen_sari_tl(s->tmp0, s->T1, 3 + ot);
- tcg_gen_shli_tl(s->tmp0, s->tmp0, ot);
- tcg_gen_add_tl(s->A0, gen_lea_modrm_1(s, a, false), s->tmp0);
- gen_lea_v_seg(s, s->A0, a.def_seg, s->override);
- if (!(s->prefix & PREFIX_LOCK)) {
- gen_op_ld_v(s, ot, s->T0, s->A0);
- }
- } else {
- gen_op_mov_v_reg(s, ot, s->T0, rm);
- }
- bt_op:
- tcg_gen_andi_tl(s->T1, s->T1, (1 << (3 + ot)) - 1);
- tcg_gen_movi_tl(s->tmp0, 1);
- tcg_gen_shl_tl(s->tmp0, s->tmp0, s->T1);
- if (s->prefix & PREFIX_LOCK) {
- switch (op) {
- case 0: /* bt */
- /* Needs no atomic ops; we suppressed the normal
- memory load for LOCK above so do it now. */
- gen_op_ld_v(s, ot, s->T0, s->A0);
- break;
- case 1: /* bts */
- tcg_gen_atomic_fetch_or_tl(s->T0, s->A0, s->tmp0,
- s->mem_index, ot | MO_LE);
- break;
- case 2: /* btr */
- tcg_gen_not_tl(s->tmp0, s->tmp0);
- tcg_gen_atomic_fetch_and_tl(s->T0, s->A0, s->tmp0,
- s->mem_index, ot | MO_LE);
- break;
- default:
- case 3: /* btc */
- tcg_gen_atomic_fetch_xor_tl(s->T0, s->A0, s->tmp0,
- s->mem_index, ot | MO_LE);
- break;
- }
- tcg_gen_shr_tl(s->tmp4, s->T0, s->T1);
- } else {
- tcg_gen_shr_tl(s->tmp4, s->T0, s->T1);
- switch (op) {
- case 0: /* bt */
- /* Data already loaded; nothing to do. */
- break;
- case 1: /* bts */
- tcg_gen_or_tl(s->T0, s->T0, s->tmp0);
- break;
- case 2: /* btr */
- tcg_gen_andc_tl(s->T0, s->T0, s->tmp0);
- break;
- default:
- case 3: /* btc */
- tcg_gen_xor_tl(s->T0, s->T0, s->tmp0);
- break;
- }
- if (op != 0) {
- if (mod != 3) {
- gen_op_st_v(s, ot, s->T0, s->A0);
- } else {
- gen_op_mov_reg_v(s, ot, rm, s->T0);
- }
- }
- }
-
- /* Delay all CC updates until after the store above. Note that
- C is the result of the test, Z is unchanged, and the others
- are all undefined. */
- switch (s->cc_op) {
- case CC_OP_MULB ... CC_OP_MULQ:
- case CC_OP_ADDB ... CC_OP_ADDQ:
- case CC_OP_ADCB ... CC_OP_ADCQ:
- case CC_OP_SUBB ... CC_OP_SUBQ:
- case CC_OP_SBBB ... CC_OP_SBBQ:
- case CC_OP_LOGICB ... CC_OP_LOGICQ:
- case CC_OP_INCB ... CC_OP_INCQ:
- case CC_OP_DECB ... CC_OP_DECQ:
- case CC_OP_SHLB ... CC_OP_SHLQ:
- case CC_OP_SARB ... CC_OP_SARQ:
- case CC_OP_BMILGB ... CC_OP_BMILGQ:
- /* Z was going to be computed from the non-zero status of CC_DST.
- We can get that same Z value (and the new C value) by leaving
- CC_DST alone, setting CC_SRC, and using a CC_OP_SAR of the
- same width. */
- tcg_gen_mov_tl(cpu_cc_src, s->tmp4);
- set_cc_op(s, ((s->cc_op - CC_OP_MULB) & 3) + CC_OP_SARB);
- break;
- default:
- /* Otherwise, generate EFLAGS and replace the C bit. */
- gen_compute_eflags(s);
- tcg_gen_deposit_tl(cpu_cc_src, cpu_cc_src, s->tmp4,
- ctz32(CC_C), 1);
- break;
- }
- break;
case 0x1bc: /* bsf / tzcnt */
case 0x1bd: /* bsr / lzcnt */
ot = dflag;
diff --git a/target/i386/tcg/decode-new.c.inc b/target/i386/tcg/decode-new.c.inc
index 1db9d1e2bc3..af142d6911a 100644
--- a/target/i386/tcg/decode-new.c.inc
+++ b/target/i386/tcg/decode-new.c.inc
@@ -205,6 +205,7 @@
#define sextT0 .special = X86_SPECIAL_SExtT0,
#define zextT0 .special = X86_SPECIAL_ZExtT0,
#define op0_Mw .special = X86_SPECIAL_Op0_Mw,
+#define btEvGv .special = X86_SPECIAL_BitTest,
#define vex1 .vex_class = 1,
#define vex1_rep3 .vex_class = 1, .vex_special = X86_VEX_REPScalar,
@@ -269,6 +270,24 @@ static inline const X86OpEntry *decode_by_prefix(DisasContext *s, const X86OpEnt
}
}
+static void decode_group8(DisasContext *s, CPUX86State *env, X86OpEntry *entry, uint8_t *b)
+{
+ static const X86GenFunc group8_gen[8] = {
+ NULL, NULL, NULL, NULL,
+ gen_BT, gen_BTS, gen_BTR, gen_BTC,
+ };
+ int op = (get_modrm(s, env) >> 3) & 7;
+ entry->gen = group8_gen[op];
+ if (op == 4) {
+ /* prevent writeback and LOCK for BT */
+ entry->op1 = entry->op0;
+ entry->op0 = X86_TYPE_None;
+ entry->s0 = X86_SIZE_None;
+ } else {
+ entry->special = X86_SPECIAL_HasLock;
+ }
+}
+
static void decode_group15(DisasContext *s, CPUX86State *env, X86OpEntry *entry, uint8_t *b)
{
static const X86OpEntry group15_reg[8] = {
@@ -1114,8 +1133,10 @@ static const X86OpEntry opcodes_0F[256] = {
[0xa0] = X86_OP_ENTRYr(PUSH, FS, w),
[0xa1] = X86_OP_ENTRYw(POP, FS, w),
[0xa2] = X86_OP_ENTRY0(CPUID),
+ [0xa3] = X86_OP_ENTRYrr(BT, E,v, G,v, btEvGv),
[0xb2] = X86_OP_ENTRY3(LSS, G,v, EM,p, None, None),
+ [0xb3] = X86_OP_ENTRY2(BTR, E,v, G,v, btEvGv),
[0xb4] = X86_OP_ENTRY3(LFS, G,v, EM,p, None, None),
[0xb5] = X86_OP_ENTRY3(LGS, G,v, EM,p, None, None),
[0xb6] = X86_OP_ENTRY3(MOV, G,v, E,b, None, None, zextT0), /* MOVZX */
@@ -1240,6 +1261,7 @@ static const X86OpEntry opcodes_0F[256] = {
[0xa8] = X86_OP_ENTRYr(PUSH, GS, w),
[0xa9] = X86_OP_ENTRYw(POP, GS, w),
[0xaa] = X86_OP_ENTRY0(RSM, chk(smm) svm(RSM)),
+ [0xab] = X86_OP_ENTRY2(BTS, E,v, G,v, btEvGv),
[0xae] = X86_OP_GROUP0(group15),
/*
* It's slightly more efficient to put Ev operand in T0 and allow gen_IMUL3
@@ -1249,6 +1271,8 @@ static const X86OpEntry opcodes_0F[256] = {
/* decoded as modrm, which is visible as a difference between page fault and #UD */
[0xb9] = X86_OP_ENTRYr(UD, nop,v), /* UD1 */
+ [0xba] = X86_OP_GROUP2(group8, E,v, I,b),
+ [0xbb] = X86_OP_ENTRY2(BTC, E,v, G,v, btEvGv),
[0xbe] = X86_OP_ENTRY3(MOV, G,v, E,b, None, None, sextT0), /* MOVSX */
[0xbf] = X86_OP_ENTRY3(MOV, G,v, E,w, None, None, sextT0), /* MOVSX */
@@ -2359,6 +2383,7 @@ static void disas_insn(DisasContext *s, CPUState *cpu)
CPUX86State *env = cpu_env(cpu);
X86DecodedInsn decode;
X86DecodeFunc decode_func = decode_root;
+ bool accept_lock = false;
uint8_t cc_live, b;
s->pc = s->base.pc_next;
@@ -2532,12 +2557,11 @@ static void disas_insn(DisasContext *s, CPUState *cpu)
switch (b) {
case 0x00 ... 0x01: /* mostly privileged instructions */
case 0x1a ... 0x1b: /* MPX */
- case 0xa3 ... 0xa5: /* BT, SHLD */
- case 0xab ... 0xad: /* BTS, SHRD */
+ case 0xa4 ... 0xa5: /* SHLD */
+ case 0xac ... 0xad: /* SHRD */
case 0xb0 ... 0xb1: /* cmpxchg */
- case 0xb3: /* btr */
- case 0xb8: /* integer ops */
- case 0xba ... 0xbd: /* integer ops */
+ case 0xb8: /* POPCNT */
+ case 0xbc ... 0xbd: /* LZCNT/TZCNT */
case 0xc0 ... 0xc1: /* xadd */
case 0xc7: /* grp9 */
disas_insn_old(s, cpu, b + 0x100);
@@ -2600,9 +2624,10 @@ static void disas_insn(DisasContext *s, CPUState *cpu)
if (decode.op[0].has_ea) {
s->prefix |= PREFIX_LOCK;
}
- decode.e.special = X86_SPECIAL_HasLock;
/* fallthrough */
case X86_SPECIAL_HasLock:
+ case X86_SPECIAL_BitTest:
+ accept_lock = decode.op[0].has_ea;
break;
case X86_SPECIAL_Op0_Rd:
@@ -2644,10 +2669,8 @@ static void disas_insn(DisasContext *s, CPUState *cpu)
break;
}
- if (s->prefix & PREFIX_LOCK) {
- if (decode.e.special != X86_SPECIAL_HasLock || !decode.op[0].has_ea) {
- goto illegal_op;
- }
+ if ((s->prefix & PREFIX_LOCK) && !accept_lock) {
+ goto illegal_op;
}
if (!validate_vex(s, &decode)) {
@@ -2693,7 +2716,7 @@ static void disas_insn(DisasContext *s, CPUState *cpu)
if (decode.e.special != X86_SPECIAL_NoLoadEA &&
(decode.op[0].has_ea || decode.op[1].has_ea || decode.op[2].has_ea)) {
- gen_load_ea(s, &decode.mem, decode.e.vex_class == 12);
+ gen_load_ea(s, &decode);
}
if (s->prefix & PREFIX_LOCK) {
gen_load(s, &decode, 2, s->T1);
diff --git a/target/i386/tcg/emit.c.inc b/target/i386/tcg/emit.c.inc
index f788e1fa4c8..41398e5130c 100644
--- a/target/i386/tcg/emit.c.inc
+++ b/target/i386/tcg/emit.c.inc
@@ -73,9 +73,25 @@ static void gen_NM_exception(DisasContext *s)
gen_exception(s, EXCP07_PREX);
}
-static void gen_load_ea(DisasContext *s, AddressParts *mem, bool is_vsib)
+static void gen_load_ea(DisasContext *s, X86DecodedInsn *decode)
{
- TCGv ea = gen_lea_modrm_1(s, *mem, is_vsib);
+ AddressParts *mem = &decode->mem;
+ TCGv ea;
+
+ ea = gen_lea_modrm_1(s, *mem, decode->e.vex_class == 12);
+ if (decode->e.special == X86_SPECIAL_BitTest) {
+ int oplen = 3 + decode->op[0].ot;
+ int poslen = 8 << decode->op[2].ot;
+ TCGv ofs = tcg_temp_new();
+
+ /* Extract memory displacement from T1. */
+ assert (decode->op[2].unit == X86_OP_INT);
+ tcg_gen_sextract_tl(ofs, s->T1, oplen, poslen - oplen);
+
+ tcg_gen_add_tl(s->A0, ea, ofs);
+ ea = s->A0;
+ }
+
gen_lea_v_seg(s, ea, mem->def_seg, s->override);
}
@@ -1340,6 +1356,116 @@ static void gen_BSWAP(DisasContext *s, X86DecodedInsn *decode)
tcg_gen_bswap32_tl(s->T0, s->T0, TCG_BSWAP_OZ);
}
+static TCGv gen_bt_mask(DisasContext *s, X86DecodedInsn *decode)
+{
+ MemOp ot = decode->op[1].ot;
+ TCGv mask = tcg_temp_new();
+
+ tcg_gen_andi_tl(s->T1, s->T1, (8 << ot) - 1);
+ tcg_gen_shl_tl(mask, tcg_constant_tl(1), s->T1);
+ return mask;
+}
+
+/* Expects truncated bit index in s->T1, 1 << s->T1 in MASK. */
+static void gen_bt_flags(DisasContext *s, X86DecodedInsn *decode, TCGv src, TCGv mask)
+{
+ /*
+ * C is the result of the test, Z is unchanged, and the others
+ * are all undefined.
+ */
+ switch (s->cc_op) {
+ case CC_OP_MULB ... CC_OP_MULQ:
+ case CC_OP_ADDB ... CC_OP_ADDQ:
+ case CC_OP_ADCB ... CC_OP_ADCQ:
+ case CC_OP_SUBB ... CC_OP_SUBQ:
+ case CC_OP_SBBB ... CC_OP_SBBQ:
+ case CC_OP_LOGICB ... CC_OP_LOGICQ:
+ case CC_OP_INCB ... CC_OP_INCQ:
+ case CC_OP_DECB ... CC_OP_DECQ:
+ case CC_OP_SHLB ... CC_OP_SHLQ:
+ case CC_OP_SARB ... CC_OP_SARQ:
+ case CC_OP_BMILGB ... CC_OP_BMILGQ:
+ /*
+ * Z was going to be computed from the non-zero status of CC_DST.
+ * We can get that same Z value (and the new C value) by leaving
+ * CC_DST alone, setting CC_SRC, and using a CC_OP_SAR of the
+ * same width.
+ */
+ decode->cc_src = tcg_temp_new();
+ decode->cc_dst = cpu_cc_dst;
+ decode->cc_op = ((s->cc_op - CC_OP_MULB) & 3) + CC_OP_SARB;
+ tcg_gen_shr_tl(decode->cc_src, src, s->T1);
+ break;
+
+ default:
+ /* Otherwise, generate EFLAGS and replace the C bit. */
+ decode->cc_src = tcg_temp_new();
+ decode->cc_dst = tcg_temp_new();
+ decode->cc_op = CC_OP_ADCX;
+
+ gen_mov_eflags(s, decode->cc_src);
+ tcg_gen_setcond_tl(TCG_COND_TSTNE, decode->cc_dst, src, mask);
+ break;
+ }
+}
+
+static void gen_BT(DisasContext *s, X86DecodedInsn *decode)
+{
+ TCGv mask = gen_bt_mask(s, decode);
+
+ gen_bt_flags(s, decode, s->T0, mask);
+}
+
+static void gen_BTC(DisasContext *s, X86DecodedInsn *decode)
+{
+ MemOp ot = decode->op[0].ot;
+ TCGv old = tcg_temp_new();
+ TCGv mask = gen_bt_mask(s, decode);
+
+ if (s->prefix & PREFIX_LOCK) {
+ tcg_gen_atomic_fetch_xor_tl(old, s->A0, mask, s->mem_index, ot | MO_LE);
+ } else {
+ tcg_gen_mov_tl(old, s->T0);
+ tcg_gen_xor_tl(s->T0, s->T0, mask);
+ }
+
+ gen_bt_flags(s, decode, old, mask);
+}
+
+static void gen_BTR(DisasContext *s, X86DecodedInsn *decode)
+{
+ MemOp ot = decode->op[0].ot;
+ TCGv old = tcg_temp_new();
+ TCGv mask = gen_bt_mask(s, decode);
+
+ if (s->prefix & PREFIX_LOCK) {
+ TCGv maskc = tcg_temp_new();
+ tcg_gen_not_tl(maskc, mask);
+ tcg_gen_atomic_fetch_and_tl(old, s->A0, maskc, s->mem_index, ot | MO_LE);
+ } else {
+ tcg_gen_mov_tl(old, s->T0);
+ tcg_gen_andc_tl(s->T0, s->T0, mask);
+ }
+
+ gen_bt_flags(s, decode, old, mask);
+}
+
+static void gen_BTS(DisasContext *s, X86DecodedInsn *decode)
+{
+ MemOp ot = decode->op[0].ot;
+ TCGv old = tcg_temp_new();
+ TCGv mask = gen_bt_mask(s, decode);
+
+ if (s->prefix & PREFIX_LOCK) {
+ tcg_gen_atomic_fetch_or_tl(old, s->A0, mask, s->mem_index, ot | MO_LE);
+ } else {
+ tcg_gen_mov_tl(old, s->T0);
+ tcg_gen_or_tl(s->T0, s->T0, mask);
+ }
+
+ gen_bt_flags(s, decode, old, mask);
+}
+
static void gen_BZHI(DisasContext *s, X86DecodedInsn *decode)
{
MemOp ot = decode->op[0].ot;
--
2.45.1On 6/8/24 01:41, Paolo Bonzini wrote:
> - if (mod != 3) {
> - AddressParts a = gen_lea_modrm_0(env, s, modrm);
> - /* specific case: we need to add a displacement */
> - gen_exts(ot, s->T1);
> - tcg_gen_sari_tl(s->tmp0, s->T1, 3 + ot);
> - tcg_gen_shli_tl(s->tmp0, s->tmp0, ot);
> - tcg_gen_add_tl(s->A0, gen_lea_modrm_1(s, a, false), s->tmp0);
This is not the same as
> + if (decode->e.special == X86_SPECIAL_BitTest) {
> + int oplen = 3 + decode->op[0].ot;
> + int poslen = 8 << decode->op[2].ot;
> + TCGv ofs = tcg_temp_new();
> +
> + /* Extract memory displacement from T1. */
> + assert (decode->op[2].unit == X86_OP_INT);
> + tcg_gen_sextract_tl(ofs, s->T1, oplen, poslen - oplen);
> +
> + tcg_gen_add_tl(s->A0, ea, ofs);
... this.
Combining the exts + sari into an sextract is fine, but this has lost the shli.
r~
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