https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103253
--- Comment #11 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Tamar Christina <tnfch...@gcc.gnu.org>: https://gcc.gnu.org/g:1a0bce98dcf84dd0a7b3ac67b51ac68758cc7ad0 commit r12-5369-g1a0bce98dcf84dd0a7b3ac67b51ac68758cc7ad0 Author: Tamar Christina <tamar.christ...@arm.com> Date: Thu Nov 18 11:22:11 2021 +0000 middle-end: Fix FMA detection when inspecting gimple which have no LHS. convert_mult_to_fma assumes that all gimple_assigns have a LHS set. This assumption is however not true when an IFN is kept around just for the side-effects. In those situations you have just the IFN and lhs will be null. Since there's no LHS, there also can't be any ADD and such it can't be an FMA so it's correct to just return early if no LHS. gcc/ChangeLog: PR tree-optimization/103253 * tree-ssa-math-opts.c (convert_mult_to_fma): Check for LHS. gcc/testsuite/ChangeLog: PR tree-optimization/103253 * gcc.dg/vect/pr103253.c: New test.
