https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114074
--- Comment #11 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Richard Biener <rgue...@gcc.gnu.org>: https://gcc.gnu.org/g:018ddc86b928514d7dfee024dcdeb204d5dcdd61 commit r14-9391-g018ddc86b928514d7dfee024dcdeb204d5dcdd61 Author: Richard Biener <rguent...@suse.de> Date: Fri Mar 8 13:27:12 2024 +0100 tree-optimization/114269 - 434.zeusmp regression after SCEV analysis fix The following addresses a performance regression caused by the recent SCEV analysis fix with regard to folding multiplications and undefined behavior on overflow. We do not handle (T) { a, +, b } * c but can treat sign-conversions from unsigned by performing the multiplication in the unsigned type. That's what we already do for additions (but that misses one case that turns out important). This fixes the 434.zeusmp regression for me. PR tree-optimization/114269 PR tree-optimization/114074 * tree-chrec.cc (chrec_fold_plus_1): Handle sign-conversions in the third CASE_CONVERT case as well. (chrec_fold_multiply): Handle sign-conversions from unsigned by performing the operation in the unsigned type.
