https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122083
--- Comment #14 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The trunk branch has been updated by Andrew Pinski <[email protected]>: https://gcc.gnu.org/g:decd4277e97114922ce60786a4587a31545dba94 commit r16-4260-gdecd4277e97114922ce60786a4587a31545dba94 Author: Andrew Pinski <[email protected]> Date: Fri Oct 3 20:18:07 2025 -0700 phiopt/cselim: Improve cselim-limited to commonalize all stores [PR122083] cselim (and the phiopt's cselim-limited) can commonalize a single store which makes this too limited in some/many cases. Instead let's commonalize all trailing stores as much as possible (only in the same order). The change is smallish, basically the restriction on being the only store is removed from single_trailing_store_in_bb (renamed too). And also looping to remove all of the trailing stores instead of just doing one for the pass. Note sink will do the same optimization so doing it earlier seems like a good idea because it improve change inlining size estimates. For an example with this change, early inlining can happen for min_cmp<long int> in g++.dg/opt/pr122083-1.C now; that avoids a -Wnonnull warning as the memcmp with the null argument is optimized early. It can also catch some min in phiopt1 in some cases. Bootstrapped and tested on x86_64-linux-gnu. Changes since v1: * v2: For !flag_expensive_optimizations, handle the only store rather than just the last store. PR tree-optimization/122083 gcc/ChangeLog: * tree-ssa-phiopt.cc (single_trailing_store_in_bb): Rename to ... (trailing_store_in_bb): This and take new argument to check for only store. (cond_if_else_store_replacement_limited): Update to use trailing_store_in_bb. (cond_if_else_store_replacement): Loop until cond_if_else_store_replacement_limited returns false. (pass_phiopt::execute): Instead of calling cond_if_else_store_replacement_limited once, also loop on it. gcc/testsuite/ChangeLog: * gcc.dg/tree-ssa/ssa-pre-19.c: Disable phiopt and cselim. * g++.dg/opt/pr122083-1.C: New test. * gcc.dg/tree-ssa/cselim-1.c: New test. * gcc.dg/tree-ssa/cselim-2.c: New test. Signed-off-by: Andrew Pinski <[email protected]>
