On Wed, Nov 21, 2018 at 11:20 AM Jakub Jelinek <ja...@redhat.com> wrote: > > Hi! > > On Wed, Nov 14, 2018 at 12:37:02AM +0100, Jakub Jelinek wrote: > > 2018-11-13 Jakub Jelinek <ja...@redhat.com> > > > > PR rtl-optimization/87817 > > * config/i386/i386.md (nmi2_bzhi_<mode>3, *bmi2_bzhi_<mode>3, > > *bmi2_bzhi_<mode>3_1, *bmi2_bzhi_<mode>3_1_ccz): Use IF_THEN_ELSE > > in the pattern to avoid triggering UB when operands[2] is zero. > > (tbm_bextri_<mode>): New expander. Renamed the old define_insn to ... > > (*tbm_bextri_<mode>): ... this.
OK. I thought that I already approved the patch. Oh well... Thanks, Uros. > I'd like to ping this patch, while the folding committed for the PR > often triggers and so the RTL passes see literal zero propagated there less > often, e.g. the testcase with: > -O2 -mbmi2 -fno-tree-ccp -fno-tree-forwprop -fno-tree-fre -fno-tree-pre > -fno-tree-vrp -fno-tree-dominator-opts -fno-code-hoisting > is still miscompiled and there could be other reasons why a zero appears > only after expansion. > > From what I understood, the agreement was that zero_extract with 0 size > (either literal or just at runtime is incorrect in the middle-end). > > Jakub
