https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77673
--- Comment #9 from Thomas Preud'homme <thopre01 at gcc dot gnu.org> --- Author: thopre01 Date: Wed Dec 14 09:58:23 2016 New Revision: 243635 URL: https://gcc.gnu.org/viewcvs?rev=243635&root=gcc&view=rev Log: Fix PR77673: bswap loads passed end of object 2016-12-14 Thomas Preud'homme <thomas.preudho...@arm.com> Backport from mainline 2016-11-25 Thomas Preud'homme <thomas.preudho...@arm.com> gcc/ PR tree-optimization/77673 * tree-ssa-math-opts.c (struct symbolic_number): Add new src field. (init_symbolic_number): Initialize src field from src parameter. (perform_symbolic_merge): Select most dominated statement as the source statement. Set src field of resulting n structure from the input src with the lowest address. (find_bswap_or_nop): Rename source_stmt into ins_stmt. (bswap_replace): Rename src_stmt into ins_stmt. Initially get source of load from src field rather than insertion statement. Cancel optimization if statement analyzed is not dominated by the insertion statement. (pass_optimize_bswap::execute): Rename src_stmt to ins_stmt. Compute dominance information. gcc/testsuite/ PR tree-optimization/77673 * gcc.dg/pr77673.c: New test. Added: branches/gcc-6-branch/gcc/testsuite/gcc.dg/pr77673.c Modified: branches/gcc-6-branch/gcc/ChangeLog branches/gcc-6-branch/gcc/testsuite/ChangeLog branches/gcc-6-branch/gcc/tree-ssa-math-opts.c