https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119357
--- Comment #10 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jakub Jelinek <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:9030c54d3ff983cf07752173737f627a2e458426 commit r15-8295-g9030c54d3ff983cf07752173737f627a2e458426 Author: Jakub Jelinek <ja...@redhat.com> Date: Wed Mar 19 14:26:22 2025 +0100 i386: Fix up splitters into vptest [PR119357] The following testcase ICEs, because the splitters into vptest create an invalid instruction. The operands of all the UNSPEC_PTEST using instructions use register_operand and vector_operand predicate, these splitters use vector_operand predicate but create vptest instruction which has the same argument twice, so one of them needs to be in a register. The following patch keeps vector_operand predicate on the splitters but uses force_reg to force it into a REG if it was a MEM, that results in better code generation e.g. on the included testcase, as combine can match those even with MEM. The difference on the testcase is - vpxor %xmm0, %xmm0, %xmm0 - vpcmpeqb (%rdi), %xmm0, %xmm0 - vpmovmskb %xmm0, %eax - cmpl $65535, %eax + vmovdqa (%rdi), %xmm0 + vptest %xmm0, %xmm0 (- for patch which changes the splitters to s/vector_operand/register_operand/ and + for this patch). 2025-03-19 Jakub Jelinek <ja...@redhat.com> PR target/119357 * config/i386/sse.md (pmovmskb 0xffff to ptest splitter, *pmovsk_ptest_<mode>_avx512): Force operands[0] into a REG. * gcc.target/i386/avx512vlbw-pr119357.c: New test.
