From bccb0c138e5138c86169216bce280b1ebde44e1b Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Sat, 21 Oct 2023 09:35:58 +0200 Subject: [PATCH] target/i386: extend cc_* when using them to compute flags Instead of using s->tmp0 or s->tmp4 as the result, just extend the cc_* registers in place. It is harmless and, if multiple setcc instructions are used, the optimizer will be able to remove the redundant ones. Reviewed-by: Richard Henderson Signed-off-by: Paolo Bonzini --- target/i386/tcg/translate.c | 44 +++++++++++++++---------------------- 1 file changed, 18 insertions(+), 26 deletions(-) diff --git a/target/i386/tcg/translate.c b/target/i386/tcg/translate.c index 024da6d88e..7292908adc 100644 --- a/target/i386/tcg/translate.c +++ b/target/i386/tcg/translate.c @@ -940,28 +940,24 @@ static CCPrepare gen_prepare_sign_nz(TCGv src, MemOp size) /* compute eflags.C to reg */ static CCPrepare gen_prepare_eflags_c(DisasContext *s, TCGv reg) { - TCGv t0, t1; MemOp size; switch (s->cc_op) { case CC_OP_SUBB ... CC_OP_SUBQ: /* (DATA_TYPE)CC_SRCT < (DATA_TYPE)CC_SRC */ size = s->cc_op - CC_OP_SUBB; - t1 = gen_ext_tl(s->tmp0, cpu_cc_src, size, false); - /* If no temporary was used, be careful not to alias t1 and t0. */ - t0 = t1 == cpu_cc_src ? s->tmp0 : reg; - tcg_gen_mov_tl(t0, s->cc_srcT); - gen_extu(size, t0); - goto add_sub; + gen_ext_tl(s->cc_srcT, s->cc_srcT, size, false); + gen_ext_tl(cpu_cc_src, cpu_cc_src, size, false); + return (CCPrepare) { .cond = TCG_COND_LTU, .reg = s->cc_srcT, + .reg2 = cpu_cc_src, .use_reg2 = true }; case CC_OP_ADDB ... CC_OP_ADDQ: /* (DATA_TYPE)CC_DST < (DATA_TYPE)CC_SRC */ size = s->cc_op - CC_OP_ADDB; - t1 = gen_ext_tl(s->tmp0, cpu_cc_src, size, false); - t0 = gen_ext_tl(reg, cpu_cc_dst, size, false); - add_sub: - return (CCPrepare) { .cond = TCG_COND_LTU, .reg = t0, - .reg2 = t1, .use_reg2 = true }; + gen_ext_tl(cpu_cc_dst, cpu_cc_dst, size, false); + gen_ext_tl(cpu_cc_src, cpu_cc_src, size, false); + return (CCPrepare) { .cond = TCG_COND_LTU, .reg = cpu_cc_dst, + .reg2 = cpu_cc_src, .use_reg2 = true }; case CC_OP_LOGICB ... CC_OP_LOGICQ: case CC_OP_CLR: @@ -984,8 +980,8 @@ static CCPrepare gen_prepare_eflags_c(DisasContext *s, TCGv reg) case CC_OP_BMILGB ... CC_OP_BMILGQ: size = s->cc_op - CC_OP_BMILGB; - t0 = gen_ext_tl(reg, cpu_cc_src, size, false); - return (CCPrepare) { .cond = TCG_COND_EQ, .reg = t0 }; + gen_ext_tl(cpu_cc_src, cpu_cc_src, size, false); + return (CCPrepare) { .cond = TCG_COND_EQ, .reg = cpu_cc_src }; case CC_OP_ADCX: case CC_OP_ADCOX: @@ -1098,7 +1094,6 @@ static CCPrepare gen_prepare_cc(DisasContext *s, int b, TCGv reg) int inv, jcc_op, cond; MemOp size; CCPrepare cc; - TCGv t0; inv = b & 1; jcc_op = (b >> 1) & 7; @@ -1109,24 +1104,21 @@ static CCPrepare gen_prepare_cc(DisasContext *s, int b, TCGv reg) size = s->cc_op - CC_OP_SUBB; switch (jcc_op) { case JCC_BE: - tcg_gen_mov_tl(s->tmp4, s->cc_srcT); - gen_extu(size, s->tmp4); - t0 = gen_ext_tl(s->tmp0, cpu_cc_src, size, false); - cc = (CCPrepare) { .cond = TCG_COND_LEU, .reg = s->tmp4, - .reg2 = t0, .use_reg2 = true }; + gen_ext_tl(s->cc_srcT, s->cc_srcT, size, false); + gen_ext_tl(cpu_cc_src, cpu_cc_src, size, false); + cc = (CCPrepare) { .cond = TCG_COND_LEU, .reg = s->cc_srcT, + .reg2 = cpu_cc_src, .use_reg2 = true }; break; - case JCC_L: cond = TCG_COND_LT; goto fast_jcc_l; case JCC_LE: cond = TCG_COND_LE; fast_jcc_l: - tcg_gen_mov_tl(s->tmp4, s->cc_srcT); - gen_exts(size, s->tmp4); - t0 = gen_ext_tl(s->tmp0, cpu_cc_src, size, true); - cc = (CCPrepare) { .cond = cond, .reg = s->tmp4, - .reg2 = t0, .use_reg2 = true }; + gen_ext_tl(s->cc_srcT, s->cc_srcT, size, true); + gen_ext_tl(cpu_cc_src, cpu_cc_src, size, true); + cc = (CCPrepare) { .cond = cond, .reg = s->cc_srcT, + .reg2 = cpu_cc_src, .use_reg2 = true }; break; default: -- 2.39.5