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target-i386: do not compute eflags multiple times consecutively

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After calling gen_compute_eflags, leave the computed value in cc_reg_src
and set cc_op to CC_OP_EFLAGS.  The next few patches will remove anyway
most calls to gen_compute_eflags.

As a result of this change it is more natural to remove the register
argument from gen_compute_eflags and change all the callers.

Reviewed-by: Blue Swirl <blauwirbel@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
This commit is contained in:
Richard Henderson 2013-01-23 13:03:26 -08:00
parent 1608ecca95
commit d229edce1c
1 changed files with 36 additions and 36 deletions
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72
target-i386/translate.c
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@ -845,47 +845,48 @@ static void gen_compute_eflags_c(DisasContext *s, TCGv reg)
tcg_gen_extu_i32_tl(reg, cpu_tmp2_i32);
}
/* compute all eflags to reg */
static void gen_compute_eflags(DisasContext *s, TCGv reg)
/* compute all eflags to cc_src */
static void gen_compute_eflags(DisasContext *s)
{
if (s->cc_op == CC_OP_EFLAGS) {
return;
}
gen_update_cc_op(s);
gen_helper_cc_compute_all(cpu_tmp2_i32, cpu_env, cpu_cc_op);
if (TCGV_EQUAL(reg, cpu_cc_src)) {
tcg_gen_discard_tl(cpu_cc_dst);
set_cc_op(s, CC_OP_EFLAGS);
}
tcg_gen_extu_i32_tl(reg, cpu_tmp2_i32);
tcg_gen_discard_tl(cpu_cc_dst);
set_cc_op(s, CC_OP_EFLAGS);
tcg_gen_extu_i32_tl(cpu_cc_src, cpu_tmp2_i32);
}
/* compute eflags.P to reg */
static void gen_compute_eflags_p(DisasContext *s, TCGv reg)
{
gen_compute_eflags(s, reg);
tcg_gen_shri_tl(reg, reg, 2);
gen_compute_eflags(s);
tcg_gen_shri_tl(reg, cpu_cc_src, 2);
tcg_gen_andi_tl(reg, reg, 1);
}
/* compute eflags.S to reg */
static void gen_compute_eflags_s(DisasContext *s, TCGv reg)
{
gen_compute_eflags(s, reg);
tcg_gen_shri_tl(reg, reg, 7);
gen_compute_eflags(s);
tcg_gen_shri_tl(reg, cpu_cc_src, 7);
tcg_gen_andi_tl(reg, reg, 1);
}
/* compute eflags.O to reg */
static void gen_compute_eflags_o(DisasContext *s, TCGv reg)
{
gen_compute_eflags(s, reg);
tcg_gen_shri_tl(reg, reg, 11);
gen_compute_eflags(s);
tcg_gen_shri_tl(reg, cpu_cc_src, 11);
tcg_gen_andi_tl(reg, reg, 1);
}
/* compute eflags.Z to reg */
static void gen_compute_eflags_z(DisasContext *s, TCGv reg)
{
gen_compute_eflags(s, reg);
tcg_gen_shri_tl(reg, reg, 6);
gen_compute_eflags(s);
tcg_gen_shri_tl(reg, cpu_cc_src, 6);
tcg_gen_andi_tl(reg, reg, 1);
}
@ -902,9 +903,9 @@ static inline void gen_setcc_slow_T0(DisasContext *s, int jcc_op)
gen_compute_eflags_z(s, cpu_T[0]);
break;
case JCC_BE:
gen_compute_eflags(s, cpu_tmp0);
tcg_gen_shri_tl(cpu_T[0], cpu_tmp0, 6);
tcg_gen_or_tl(cpu_T[0], cpu_T[0], cpu_tmp0);
gen_compute_eflags(s);
tcg_gen_shri_tl(cpu_T[0], cpu_cc_src, 6);
tcg_gen_or_tl(cpu_T[0], cpu_T[0], cpu_cc_src);
tcg_gen_andi_tl(cpu_T[0], cpu_T[0], 1);
break;
case JCC_S:
@ -914,18 +915,18 @@ static inline void gen_setcc_slow_T0(DisasContext *s, int jcc_op)
gen_compute_eflags_p(s, cpu_T[0]);
break;
case JCC_L:
gen_compute_eflags(s, cpu_tmp0);
tcg_gen_shri_tl(cpu_T[0], cpu_tmp0, 11); /* CC_O */
tcg_gen_shri_tl(cpu_tmp0, cpu_tmp0, 7); /* CC_S */
gen_compute_eflags(s);
tcg_gen_shri_tl(cpu_T[0], cpu_cc_src, 11); /* CC_O */
tcg_gen_shri_tl(cpu_tmp0, cpu_cc_src, 7); /* CC_S */
tcg_gen_xor_tl(cpu_T[0], cpu_T[0], cpu_tmp0);
tcg_gen_andi_tl(cpu_T[0], cpu_T[0], 1);
break;
default:
case JCC_LE:
gen_compute_eflags(s, cpu_tmp0);
tcg_gen_shri_tl(cpu_T[0], cpu_tmp0, 11); /* CC_O */
tcg_gen_shri_tl(cpu_tmp4, cpu_tmp0, 7); /* CC_S */
tcg_gen_shri_tl(cpu_tmp0, cpu_tmp0, 6); /* CC_Z */
gen_compute_eflags(s);
tcg_gen_shri_tl(cpu_T[0], cpu_cc_src, 11); /* CC_O */
tcg_gen_shri_tl(cpu_tmp4, cpu_cc_src, 7); /* CC_S */
tcg_gen_shri_tl(cpu_tmp0, cpu_cc_src, 6); /* CC_Z */
tcg_gen_xor_tl(cpu_T[0], cpu_T[0], cpu_tmp4);
tcg_gen_or_tl(cpu_T[0], cpu_T[0], cpu_tmp0);
tcg_gen_andi_tl(cpu_T[0], cpu_T[0], 1);
@ -1619,7 +1620,7 @@ static void gen_rot_rm_T1(DisasContext *s, int ot, int op1,
}
/* update eflags. It is needed anyway most of the time, do it always. */
gen_compute_eflags(s, cpu_cc_src);
gen_compute_eflags(s);
assert(s->cc_op == CC_OP_EFLAGS);
label2 = gen_new_label();
@ -1696,7 +1697,7 @@ static void gen_rot_rm_im(DisasContext *s, int ot, int op1, int op2,
if (op2 != 0) {
/* update eflags */
gen_compute_eflags(s, cpu_cc_src);
gen_compute_eflags(s);
assert(s->cc_op == CC_OP_EFLAGS);
tcg_gen_andi_tl(cpu_cc_src, cpu_cc_src, ~(CC_O | CC_C));
@ -1720,8 +1721,7 @@ static void gen_rot_rm_im(DisasContext *s, int ot, int op1, int op2,
static void gen_rotc_rm_T1(DisasContext *s, int ot, int op1,
int is_right)
{
gen_update_cc_op(s);
gen_compute_eflags(s, cpu_cc_src);
gen_compute_eflags(s);
assert(s->cc_op == CC_OP_EFLAGS);
/* load */
@ -6483,7 +6483,7 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
if (CODE64(s) && !(s->cpuid_ext3_features & CPUID_EXT3_LAHF_LM))
goto illegal_op;
gen_op_mov_TN_reg(OT_BYTE, 0, R_AH);
gen_compute_eflags(s, cpu_cc_src);
gen_compute_eflags(s);
tcg_gen_andi_tl(cpu_cc_src, cpu_cc_src, CC_O);
tcg_gen_andi_tl(cpu_T[0], cpu_T[0], CC_S | CC_Z | CC_A | CC_P | CC_C);
tcg_gen_or_tl(cpu_cc_src, cpu_cc_src, cpu_T[0]);
@ -6491,21 +6491,21 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
case 0x9f: /* lahf */
if (CODE64(s) && !(s->cpuid_ext3_features & CPUID_EXT3_LAHF_LM))
goto illegal_op;
gen_compute_eflags(s, cpu_T[0]);
gen_compute_eflags(s);
/* Note: gen_compute_eflags() only gives the condition codes */
tcg_gen_ori_tl(cpu_T[0], cpu_T[0], 0x02);
tcg_gen_ori_tl(cpu_T[0], cpu_cc_src, 0x02);
gen_op_mov_reg_T0(OT_BYTE, R_AH);
break;
case 0xf5: /* cmc */
gen_compute_eflags(s, cpu_cc_src);
gen_compute_eflags(s);
tcg_gen_xori_tl(cpu_cc_src, cpu_cc_src, CC_C);
break;
case 0xf8: /* clc */
gen_compute_eflags(s, cpu_cc_src);
gen_compute_eflags(s);
tcg_gen_andi_tl(cpu_cc_src, cpu_cc_src, ~CC_C);
break;
case 0xf9: /* stc */
gen_compute_eflags(s, cpu_cc_src);
gen_compute_eflags(s);
tcg_gen_ori_tl(cpu_cc_src, cpu_cc_src, CC_C);
break;
case 0xfc: /* cld */
@ -7381,7 +7381,7 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
} else {
gen_op_mov_reg_v(ot, rm, t0);
}
gen_compute_eflags(s, cpu_cc_src);
gen_compute_eflags(s);
tcg_gen_andi_tl(cpu_cc_src, cpu_cc_src, ~CC_Z);
tcg_gen_or_tl(cpu_cc_src, cpu_cc_src, t2);
tcg_temp_free(t0);