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target/i386: unify REP and REPZ/REPNZ generation

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It only differs in a single call to gen_jcc, so use a "bool" argument
to distinguish the two cases; do not duplicate code.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Link: https://lore.kernel.org/r/20241215090613.89588-4-pbonzini@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2024-12-15 10:06:02 +01:00
parent e604be4fb4
commit b519556f58
1 changed files with 20 additions and 19 deletions
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39
target/i386/tcg/translate.c
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@ -1310,14 +1310,18 @@ static void gen_outs(DisasContext *s, MemOp ot)
gen_bpt_io(s, s->tmp2_i32, ot);
}
/* Generate jumps to current or next instruction */
static void gen_repz(DisasContext *s, MemOp ot,
void (*fn)(DisasContext *s, MemOp ot))
static void do_gen_rep(DisasContext *s, MemOp ot,
void (*fn)(DisasContext *s, MemOp ot),
bool is_repz_nz)
{
TCGLabel *l2;
l2 = gen_jz_ecx_string(s);
fn(s, ot);
gen_op_add_reg_im(s, s->aflag, R_ECX, -1);
if (is_repz_nz) {
int nz = (s->prefix & PREFIX_REPNZ) ? 1 : 0;
gen_jcc(s, (JCC_Z << 1) | (nz ^ 1), l2);
}
/*
* A loop would cause two single step exceptions if ECX = 1
* before rep string_insn
@ -1325,28 +1329,25 @@ static void gen_repz(DisasContext *s, MemOp ot,
if (s->repz_opt) {
gen_op_jz_ecx(s, l2);
}
/*
* For CMPS/SCAS there is no need to set CC_OP_DYNAMIC: only one iteration
* is done at a time, so the translation block ends unconditionally after
* this instruction and there is no control flow junction.
*/
gen_jmp_rel_csize(s, -cur_insn_len(s), 0);
}
static void gen_repz(DisasContext *s, MemOp ot,
void (*fn)(DisasContext *s, MemOp ot))
{
do_gen_rep(s, ot, fn, false);
}
static void gen_repz_nz(DisasContext *s, MemOp ot,
void (*fn)(DisasContext *s, MemOp ot))
{
TCGLabel *l2;
int nz = (s->prefix & PREFIX_REPNZ) ? 1 : 0;
l2 = gen_jz_ecx_string(s);
fn(s, ot);
gen_op_add_reg_im(s, s->aflag, R_ECX, -1);
gen_jcc(s, (JCC_Z << 1) | (nz ^ 1), l2);
if (s->repz_opt) {
gen_op_jz_ecx(s, l2);
}
/*
* Only one iteration is done at a time, so the translation
* block ends unconditionally after this instruction and there
* is no control flow junction - no need to set CC_OP_DYNAMIC.
*/
gen_jmp_rel_csize(s, -cur_insn_len(s), 0);
do_gen_rep(s, ot, fn, true);
}
static void gen_helper_fp_arith_ST0_FT0(int op)