On 8/8/23 08:55, Peter Maydell wrote:
On Tue, 8 Aug 2023 at 04:13, Richard Henderson <richard.hender...@linaro.org> wrote:Signed-off-by: Richard Henderson <richard.hender...@linaro.org> --- tcg/tcg-op-gvec.c | 6 ++---- tcg/tcg-op.c | 6 ++---- 2 files changed, 4 insertions(+), 8 deletions(-) diff --git a/tcg/tcg-op-gvec.c b/tcg/tcg-op-gvec.c index a062239804..e260a07c61 100644 --- a/tcg/tcg-op-gvec.c +++ b/tcg/tcg-op-gvec.c @@ -3692,8 +3692,7 @@ static void expand_cmp_i32(uint32_t dofs, uint32_t aofs, uint32_t bofs, for (i = 0; i < oprsz; i += 4) { tcg_gen_ld_i32(t0, cpu_env, aofs + i); tcg_gen_ld_i32(t1, cpu_env, bofs + i); - tcg_gen_setcond_i32(cond, t0, t0, t1); - tcg_gen_neg_i32(t0, t0); + tcg_gen_negsetcond_i32(cond, t0, t0, t1); tcg_gen_st_i32(t0, cpu_env, dofs + i); }Is it not possible for the optimizer to notice "you did a setcond followed by a neg, let me turn it into negsetcond for you" ?
Not at present, no. That sort of peephole optimization is a bit more difficult than what we do at present.
r~
