https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120333
--- Comment #3 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jeff Law <l...@gcc.gnu.org>: https://gcc.gnu.org/g:38fa6c0455ec14f2f42310a817b90765ad894aa4 commit r16-740-g38fa6c0455ec14f2f42310a817b90765ad894aa4 Author: Jeff Law <j...@ventanamicro.com> Date: Mon May 19 16:55:15 2025 -0600 [committed][RISC-V][PR target/120333] Remove bogus bext pattern I goof'd when doing analysis of missed bext cases. For the shift into the sign bit, then shift into the low bit case (thankfully the least common), I got it in my brain that the field is at the left shift count. It's actually at word_size - 1 - left shift count. One the subtraction is included, it's no longer profitable to turn those cases into bext. Best case scenario would be sub+bext, but we can just as easily use sll+srl which fuses in some designs into a single op. So this patch removes those two patterns, adjusts the existing testcase and adds the new execution test. Given it's a partial reversion and has passed in my tester, I'm going to go ahead and push it to the trunk rather than waiting for upstream CI. PR target/120333 gcc/ * config/riscv/bitmanip.md: Remove bext formed from left+right shift patterns. gcc/testsuite/ * gcc.target/riscv/pr114512.c: Update expected output. * gcc.target/riscv/pr120333.c: New test.
