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target/i386: avoid trunc and ext for MULX and RORX

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Use _tl operations for 32-bit operands on 32-bit targets, and only go
through trunc and extu ops for 64-bit targets.  While the trunc/ext
ops should be pretty much free after optimization, the optimizer also
does not like having the same temporary used in multiple EBBs.
Therefore it is nicer to not use tmpN* unless necessary.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2023-10-19 18:25:40 +02:00
parent b609db9477
commit 6dd2afed55
1 changed files with 25 additions and 12 deletions
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37
target/i386/tcg/emit.c.inc
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@ -1348,7 +1348,8 @@ static void gen_MULX(DisasContext *s, CPUX86State *env, X86DecodedInsn *decode)
/* low part of result in VEX.vvvv, high in MODRM */
switch (ot) {
default:
case MO_32:
#ifdef TARGET_X86_64
tcg_gen_trunc_tl_i32(s->tmp2_i32, s->T0);
tcg_gen_trunc_tl_i32(s->tmp3_i32, s->T1);
tcg_gen_mulu2_i32(s->tmp2_i32, s->tmp3_i32,
@ -1356,13 +1357,15 @@ static void gen_MULX(DisasContext *s, CPUX86State *env, X86DecodedInsn *decode)
tcg_gen_extu_i32_tl(cpu_regs[s->vex_v], s->tmp2_i32);
tcg_gen_extu_i32_tl(s->T0, s->tmp3_i32);
break;
#ifdef TARGET_X86_64
case MO_64:
tcg_gen_mulu2_i64(cpu_regs[s->vex_v], s->T0, s->T0, s->T1);
break;
#endif
}
case MO_64:
#endif
tcg_gen_mulu2_tl(cpu_regs[s->vex_v], s->T0, s->T0, s->T1);
break;
default:
g_assert_not_reached();
}
}
static void gen_PALIGNR(DisasContext *s, CPUX86State *env, X86DecodedInsn *decode)
@ -1765,14 +1768,24 @@ static void gen_PSLLDQ_i(DisasContext *s, CPUX86State *env, X86DecodedInsn *deco
static void gen_RORX(DisasContext *s, CPUX86State *env, X86DecodedInsn *decode)
{
MemOp ot = decode->op[0].ot;
int b = decode->immediate;
int mask = ot == MO_64 ? 63 : 31;
int b = decode->immediate & mask;
if (ot == MO_64) {
tcg_gen_rotri_tl(s->T0, s->T0, b & 63);
} else {
switch (ot) {
case MO_32:
#ifdef TARGET_X86_64
tcg_gen_trunc_tl_i32(s->tmp2_i32, s->T0);
tcg_gen_rotri_i32(s->tmp2_i32, s->tmp2_i32, b & 31);
tcg_gen_rotri_i32(s->tmp2_i32, s->tmp2_i32, b);
tcg_gen_extu_i32_tl(s->T0, s->tmp2_i32);
break;
case MO_64:
#endif
tcg_gen_rotri_tl(s->T0, s->T0, b);
break;
default:
g_assert_not_reached();
}
}