On Thu, Aug 11, 2016 at 11:56 AM, Bin.Cheng <amker.ch...@gmail.com> wrote: > On Thu, Aug 11, 2016 at 10:50 AM, Richard Biener > <richard.guent...@gmail.com> wrote: >> On Wed, Aug 10, 2016 at 5:58 PM, Bin Cheng <bin.ch...@arm.com> wrote: >>> Hi, >>> Due to some reasons, tree-if-conv.c now factors floating point comparison >>> out of cond_expr, >>> resulting in mixed types in it. This does help CSE on common comparison >>> operations. >>> Only problem is that test gcc.dg/vect/pr56541.c now requires >>> vect_cond_mixed to be >>> vectorized. This patch changes the test in that way. >>> Test result checked. Is it OK? >> >> Hmm, I think the fix is to fix if-conversion not doing that. Can you >> track down why this happens? > Hmm, but there are several common floating comparison operations in > the case, by doing this, we could do CSE on GIMPLE, otherwise we > depends on RTL optimizers.
I see. > I thought we prefer GIMPLE level > transforms? Yes, but the vectorizer is happier with the conditions present in the COND_EXPR and thus we concluded we always want to have them there. forwprop will also aggressively put them back. Note that we cannot put back tree_could_throw_p conditions (FP compares with signalling nans for example) to properly model EH (though for VEC_COND_EXPRs we don't really care here). Note that nothing between if-conversion and vectorization will perform the desired CSE anyway. Richard. > Thanks, > bin >> >> Richard. >> >>> Thanks, >>> bin >>> >>> gcc/testsuite/ChangeLog >>> 2016-08-09 Bin Cheng <bin.ch...@arm.com> >>> >>> * gcc.dg/vect/pr56541.c: Require vect_cond_mixed.
