https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78821
--- Comment #16 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Author: jakub Date: Mon Nov 20 10:10:23 2017 New Revision: 254948 URL: https://gcc.gnu.org/viewcvs?rev=254948&root=gcc&view=rev Log: PR tree-optimization/78821 * gimple-ssa-store-merging.c (find_bswap_or_nop_load): Give up if base is TARGET_MEM_REF. If base is not MEM_REF, set base_addr to the address of the base rather than the base itself. (find_bswap_or_nop_1): Just use pointer comparison for vuse check. (find_bswap_or_nop_finalize): New function. (find_bswap_or_nop): Use it. (bswap_replace): Return a tree rather than bool, change first argument from gimple * to gimple_stmt_iterator, allow inserting into an empty sequence, allow ins_stmt to be NULL - then emit all stmts into gsi. Fix up MEM_REF address gimplification. (pass_optimize_bswap::execute): Adjust bswap_replace caller. (struct store_immediate_info): Add N and INS_STMT non-static data members. (store_immediate_info::store_immediate_info): Initialize them from newly added ctor args. (merged_store_group::apply_stores): Formatting fixes. Sort by bitpos at the end. (stmts_may_clobber_ref_p): For stores call also refs_anti_dependent_p. (gather_bswap_load_refs): New function. (imm_store_chain_info::try_coalesce_bswap): New method. (imm_store_chain_info::coalesce_immediate_stores): Use it. (split_group): Handle LROTATE_EXPR and NOP_EXPR rhs_code specially. (imm_store_chain_info::output_merged_store): Fail if number of new estimated stmts is bigger or equal than old. Handle LROTATE_EXPR and NOP_EXPR rhs_code. (pass_store_merging::process_store): Compute n and ins_stmt, if ins_stmt is non-NULL and the store rhs is otherwise invalid, use LROTATE_EXPR rhs_code. Pass n and ins_stmt to store_immediate_info ctor. (pass_store_merging::execute): Calculate dominators. * gcc.dg/store_merging_16.c: New test. Added: trunk/gcc/testsuite/gcc.dg/store_merging_16.c Modified: trunk/gcc/ChangeLog trunk/gcc/gimple-ssa-store-merging.c trunk/gcc/testsuite/ChangeLog