https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99025
--- Comment #4 from CVS 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:20482cfcc1d3b71e0aec57b5b48685bf0b5402ca commit r11-7177-g20482cfcc1d3b71e0aec57b5b48685bf0b5402ca Author: Jakub Jelinek <ja...@redhat.com> Date: Wed Feb 10 19:50:11 2021 +0100 i386: Fix ICEs due to simplify_gen_subreg returning NULL [PR99025] In these patterns, we call simplify_gen_subreg on the input operand to create paradoxical subregs that have 2x, 4x or 8x elements as the input operand. That works fine if the input operand is a REG, but when it is a SUBREG, RTL doesn't allow SUBREG of SUBREG and so relies on simplify_subreg actually simplifying it. And e.g. if the input operand is a SUBREG that changes the element mode (floating vs. non-floating) and then combined with a paradoxical subreg (i.e. different size) this can easily fail, then simplify_gen_subreg returns NULL but we still use it in instructions. Fixed by forcing the operands into REG. 2021-02-10 Jakub Jelinek <ja...@redhat.com> PR target/99025 * config/i386/sse.md (fix<fixunssuffix>_truncv2sfv2di2, <insn>v8qiv8hi2, <insn>v8qiv8si2, <insn>v4qiv4si2, <insn>v4hiv4si2, <insn>v8qiv8di2, <insn>v4qiv4di2, <insn>v2qiv2di2, <insn>v4hiv4di2, <insn>v2hiv2di2, <insn>v2siv2di2): Force operands[1] into REG before calling simplify_gen_subreg on it. * gcc.target/i386/pr99025.c: New test.
