https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112694
--- Comment #8 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Robin Dapp <rd...@gcc.gnu.org>: https://gcc.gnu.org/g:99eef0cfa56573c32b9c0a1e43519ee4300ac63f commit r15-6279-g99eef0cfa56573c32b9c0a1e43519ee4300ac63f Author: Robin Dapp <rd...@ventanamicro.com> Date: Fri Sep 6 16:04:03 2024 +0200 vect: Do not try to duplicate_and_interleave one-element mode. PR112694 shows that we try to create sub-vectors of single-element vectors because can_duplicate_and_interleave_p returns true. The problem resurfaced in PR116611. This patch makes can_duplicate_and_interleave_p return false if count / nvectors > 0 and removes the corresponding check in the riscv backend. This partially gets rid of the FAIL in slp-19a.c. At least when built with cost model we don't have LOAD_LANES anymore. Without cost model, as in the test suite, we choose a different path and still end up with LOAD_LANES. Bootstrapped and regtested on x86 and power10, regtested on rv64gcv_zvfh_zvbb. Still waiting for the aarch64 results. Regards Robin gcc/ChangeLog: PR target/112694 PR target/116611. * config/riscv/riscv-v.cc (expand_vec_perm_const): Remove early return. * tree-vect-slp.cc (can_duplicate_and_interleave_p): Return false when we cannot create sub-elements.
