https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96849
--- Comment #4 from Hongtao.liu <crazylht at gmail dot com> --- Fixed in GCC11 by https://gcc.gnu.org/g:1aa71af09350b9ff4d2fad88a440b682545682ec commit r11-2947-g1aa71af09350b9ff4d2fad88a440b682545682ec Author: liuhongt <hongtao....@intel.com> Date: Tue Aug 11 11:05:40 2020 +0800 Refine expander vec_unpacku_float_hi_v16si/vec_unpacku_float_lo_v16si gcc/ PR target/96551 * config/i386/sse.md (vec_unpacku_float_hi_v16si): For vector compare to integer mask, don't use gen_rtx_LT, use ix86_expand_mask_vec_cmp instead. (vec_unpacku_float_hi_v16si): Ditto. gcc/testsuite * gcc.target/i386/avx512f-pr96551-1.c: New test. * gcc.target/i386/avx512f-pr96551-2.c: New test. Also backport to GCC10.