https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94650
--- Comment #3 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Uros Bizjak <u...@gcc.gnu.org>: https://gcc.gnu.org/g:8ea03e9016cbca5a7ee2b4befa4d5c32467b0982 commit r11-37-g8ea03e9016cbca5a7ee2b4befa4d5c32467b0982 Author: Uros Bizjak <ubiz...@gmail.com> Date: Mon May 4 13:49:14 2020 +0200 i386: Use SHR to compare with large power-of-two constants [PR94650] Convert unsigned compares where m >= LARGE_POWER_OF_TWO and LARGE_POWER_OF_TWO represent an immediate where bit 33+ is set to use a SHR instruction and compare the result to 0. This avoids loading a large immediate with MOVABS insn. movabsq $1099511627775, %rax cmpq %rax, %rdi ja .L5 gets converted to: shrq $40, %rdi jne .L5 PR target/94650 * config/i386/predicates.md (shr_comparison_operator): New predicate. * config/i386/i386.md (compare->shr splitter): New splitters. testsuite/ChangeLog: PR target/94650 * gcc.targeti/i386/pr94650.c: New test.
