https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125215
--- Comment #14 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-15 branch has been updated by Robin Dapp <[email protected]>: https://gcc.gnu.org/g:eea6435cd4edffb9fb50e1b58efa1f51c3f99d6a commit r15-11298-geea6435cd4edffb9fb50e1b58efa1f51c3f99d6a Author: Zhongyao Chen <[email protected]> Date: Mon Jun 15 22:21:00 2026 +0200 RISC-V: Remove interleaved vector synthesis optimization [PR125215] This patch removes the "hi/lo" optimization path in interleaved stepped constant vector synthesis. This optimization was found to be not really better than the fallback merge version. Once the overflow issue is fixed, the extra masking makes the code generation "even worse". So remove it instead of fixing. Obsolete tests slp-interleave-[1-5].c are also removed as they were specifically designed to verify this now-removed path. My local test shows no regression. PR target/125215 gcc/ChangeLog: * config/riscv/riscv-v.cc (expand_const_vector_interleaved_stepped_npatterns): Remove hi/lo optimization and always use the merge fallback. gcc/testsuite/ChangeLog: * gcc.target/riscv/rvv/autovec/pr125215.c: New test. * gcc.target/riscv/rvv/autovec/slp-interleave-1.c: Remove. * gcc.target/riscv/rvv/autovec/slp-interleave-2.c: Remove. * gcc.target/riscv/rvv/autovec/slp-interleave-3.c: Remove. * gcc.target/riscv/rvv/autovec/slp-interleave-4.c: Remove. * gcc.target/riscv/rvv/autovec/slp-interleave-5.c: Remove.
