Like the previous commit but for strlen copy so we can backport this commit. The loads should have the correct alignment on them so we need to create newly aligned types when the alignment of the pointer is less than the alignment of the current type.
Pushed as pre-approved by https://gcc.gnu.org/pipermail/gcc-patches/2025-September/694016.html after a bootstrap/test on x86_64-linux-gnu. PR tree-optimization/121776 gcc/ChangeLog: * tree-ssa-strlen.cc (strlen_pass::handle_builtin_memcmp): Create unaligned types if the alignment of the pointers is less than the alignment of the new type. Signed-off-by: Andrew Pinski <[email protected]> (cherry picked from commit caa1c2f42691d68af4d894a5c3e700ecd2dba080) (cherry picked from commit 21866f27110c1d6370f66050b9fa4fafb0a4f01b) --- gcc/tree-ssa-strlen.cc | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/gcc/tree-ssa-strlen.cc b/gcc/tree-ssa-strlen.cc index fcd40ded449..15ba0d4949a 100644 --- a/gcc/tree-ssa-strlen.cc +++ b/gcc/tree-ssa-strlen.cc @@ -4011,8 +4011,16 @@ strlen_pass::handle_builtin_memcmp () tree ptrtype = build_pointer_type_for_mode (char_type_node, ptr_mode, true); off = build_int_cst (ptrtype, 0); - arg1 = build2_loc (loc, MEM_REF, type, arg1, off); - arg2 = build2_loc (loc, MEM_REF, type, arg2, off); + + /* Create unaligned types if needed. */ + tree type1 = type, type2 = type; + if (TYPE_ALIGN (type1) > align1) + type1 = build_aligned_type (type1, align1); + if (TYPE_ALIGN (type2) > align2) + type2 = build_aligned_type (type2, align2); + + arg1 = build2_loc (loc, MEM_REF, type1, arg1, off); + arg2 = build2_loc (loc, MEM_REF, type2, arg2, off); tree tem1 = fold_const_aggregate_ref (arg1); if (tem1) arg1 = tem1; -- 2.43.0
