https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90271
--- Comment #11 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Author: jakub Date: Mon May 6 21:50:14 2019 New Revision: 270924 URL: https://gcc.gnu.org/viewcvs?rev=270924&root=gcc&view=rev Log: PR tree-optimization/88709 PR tree-optimization/90271 * params.def (PARAM_STORE_MERGING_MAX_SIZE): New parameter. * gimple-ssa-store-merging.c (encode_tree_to_bitpos): Handle non-clobber CONSTRUCTORs with no elts. Remove useless tmp_int variable. (imm_store_chain_info::coalesce_immediate_stores): Punt if the size of the store merging group is larger than PARAM_STORE_MERGING_MAX_SIZE parameter. (split_group): Add bzero_first argument. If set, always emit first the first store which must be = {} of the whole area and then for the rest of the stores consider all zero bytes as paddings. (imm_store_chain_info::output_merged_store): Check if first store is = {} of the whole area and if yes, determine which setting of bzero_first for split_group gives smaller number of stores. Adjust split_group callers. (lhs_valid_for_store_merging_p): Allow decls. (rhs_valid_for_store_merging_p): Allow non-clobber CONTRUCTORs with no elts. (pass_store_merging::process_store): Likewise. * gcc.dg/store_merging_26.c: New test. * gcc.dg/store_merging_27.c: New test. * gcc.dg/store_merging_28.c: New test. * gcc.dg/store_merging_29.c: New test. Added: trunk/gcc/testsuite/gcc.dg/store_merging_26.c trunk/gcc/testsuite/gcc.dg/store_merging_27.c trunk/gcc/testsuite/gcc.dg/store_merging_28.c trunk/gcc/testsuite/gcc.dg/store_merging_29.c Modified: trunk/gcc/ChangeLog trunk/gcc/gimple-ssa-store-merging.c trunk/gcc/params.def trunk/gcc/testsuite/ChangeLog
