[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[PATCH for-9.1 02/19] target/i386: use TSTEQ/TSTNE to check flags
From: |
Paolo Bonzini |
Subject: |
[PATCH for-9.1 02/19] target/i386: use TSTEQ/TSTNE to check flags |
Date: |
Tue, 9 Apr 2024 18:43:06 +0200 |
The new conditions obviously come in handy when testing individual bits
of EFLAGS, and they make it possible to remove the .mask field of
CCPrepare.
Lowering to shift+and is done by the optimizer if necessary.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
target/i386/tcg/translate.c | 32 ++++++++++++++++----------------
1 file changed, 16 insertions(+), 16 deletions(-)
diff --git a/target/i386/tcg/translate.c b/target/i386/tcg/translate.c
index b7117393961..4de5090846a 100644
--- a/target/i386/tcg/translate.c
+++ b/target/i386/tcg/translate.c
@@ -996,8 +996,8 @@ static CCPrepare gen_prepare_eflags_c(DisasContext *s, TCGv
reg)
case CC_OP_EFLAGS:
case CC_OP_SARB ... CC_OP_SARQ:
/* CC_SRC & 1 */
- return (CCPrepare) { .cond = TCG_COND_NE,
- .reg = cpu_cc_src, .mask = CC_C };
+ return (CCPrepare) { .cond = TCG_COND_TSTNE,
+ .reg = cpu_cc_src, .mask = -1, .imm = CC_C };
default:
/* The need to compute only C from CC_OP_DYNAMIC is important
@@ -1014,8 +1014,8 @@ static CCPrepare gen_prepare_eflags_c(DisasContext *s,
TCGv reg)
static CCPrepare gen_prepare_eflags_p(DisasContext *s, TCGv reg)
{
gen_compute_eflags(s);
- return (CCPrepare) { .cond = TCG_COND_NE, .reg = cpu_cc_src,
- .mask = CC_P };
+ return (CCPrepare) { .cond = TCG_COND_TSTNE, .reg = cpu_cc_src,
+ .mask = -1, .imm = CC_P };
}
/* compute eflags.S to reg */
@@ -1029,8 +1029,8 @@ static CCPrepare gen_prepare_eflags_s(DisasContext *s,
TCGv reg)
case CC_OP_ADCX:
case CC_OP_ADOX:
case CC_OP_ADCOX:
- return (CCPrepare) { .cond = TCG_COND_NE, .reg = cpu_cc_src,
- .mask = CC_S };
+ return (CCPrepare) { .cond = TCG_COND_TSTNE, .reg = cpu_cc_src,
+ .mask = -1, .imm = CC_S };
case CC_OP_CLR:
case CC_OP_POPCNT:
return (CCPrepare) { .cond = TCG_COND_NEVER, .mask = -1 };
@@ -1058,8 +1058,8 @@ static CCPrepare gen_prepare_eflags_o(DisasContext *s,
TCGv reg)
.reg = cpu_cc_src, .mask = -1 };
default:
gen_compute_eflags(s);
- return (CCPrepare) { .cond = TCG_COND_NE, .reg = cpu_cc_src,
- .mask = CC_O };
+ return (CCPrepare) { .cond = TCG_COND_TSTNE, .reg = cpu_cc_src,
+ .mask = -1, .imm = CC_O };
}
}
@@ -1074,8 +1074,8 @@ static CCPrepare gen_prepare_eflags_z(DisasContext *s,
TCGv reg)
case CC_OP_ADCX:
case CC_OP_ADOX:
case CC_OP_ADCOX:
- return (CCPrepare) { .cond = TCG_COND_NE, .reg = cpu_cc_src,
- .mask = CC_Z };
+ return (CCPrepare) { .cond = TCG_COND_TSTNE, .reg = cpu_cc_src,
+ .mask = -1, .imm = CC_Z };
case CC_OP_CLR:
return (CCPrepare) { .cond = TCG_COND_ALWAYS, .mask = -1 };
case CC_OP_POPCNT:
@@ -1153,8 +1153,8 @@ static CCPrepare gen_prepare_cc(DisasContext *s, int b,
TCGv reg)
break;
case JCC_BE:
gen_compute_eflags(s);
- cc = (CCPrepare) { .cond = TCG_COND_NE, .reg = cpu_cc_src,
- .mask = CC_Z | CC_C };
+ cc = (CCPrepare) { .cond = TCG_COND_TSTNE, .reg = cpu_cc_src,
+ .mask = -1, .imm = CC_Z | CC_C };
break;
case JCC_S:
cc = gen_prepare_eflags_s(s, reg);
@@ -1168,8 +1168,8 @@ static CCPrepare gen_prepare_cc(DisasContext *s, int b,
TCGv reg)
reg = s->tmp0;
}
tcg_gen_addi_tl(reg, cpu_cc_src, CC_O - CC_S);
- cc = (CCPrepare) { .cond = TCG_COND_NE, .reg = reg,
- .mask = CC_O };
+ cc = (CCPrepare) { .cond = TCG_COND_TSTNE, .reg = reg,
+ .mask = -1, .imm = CC_O };
break;
default:
case JCC_LE:
@@ -1178,8 +1178,8 @@ static CCPrepare gen_prepare_cc(DisasContext *s, int b,
TCGv reg)
reg = s->tmp0;
}
tcg_gen_addi_tl(reg, cpu_cc_src, CC_O - CC_S);
- cc = (CCPrepare) { .cond = TCG_COND_NE, .reg = reg,
- .mask = CC_O | CC_Z };
+ cc = (CCPrepare) { .cond = TCG_COND_TSTNE, .reg = reg,
+ .mask = -1, .imm = CC_O | CC_Z };
break;
}
break;
--
2.44.0
- [PATCH for-9.1 00/19] target/i386: convert 1-byte opcodes to new decoder, Paolo Bonzini, 2024/04/09
- [PATCH for-9.1 01/19] target/i386: use TSTEQ/TSTNE to test low bits, Paolo Bonzini, 2024/04/09
- [PATCH for-9.1 02/19] target/i386: use TSTEQ/TSTNE to check flags,
Paolo Bonzini <=
- [PATCH for-9.1 03/19] target/i386: remove mask from CCPrepare, Paolo Bonzini, 2024/04/09
- [PATCH for-9.1 04/19] target/i386: do not use s->tmp0 and s->tmp4 to compute flags, Paolo Bonzini, 2024/04/09
- [PATCH for-9.1 06/19] target/i386: move 00-5F opcodes to new decoder, Paolo Bonzini, 2024/04/09
- [PATCH for-9.1 05/19] target/i386: reintroduce debugging mechanism, Paolo Bonzini, 2024/04/09
- [PATCH for-9.1 07/19] target/i386: extract gen_far_call/jmp, reordering temporaries, Paolo Bonzini, 2024/04/09