Hi,
PR78646 identifies a case where the base expression for a strength-reduced
memory reference gets a type of insufficient alignment. This pointed out
the fact that we should use the type of the candidate expression for the
new base expression in all cases. Patch by Stefan M. Freudenberger.
Bootstrapped and tested on powerpc64le-unknown-linux-gnu with no regressions.
Tested with a powerpc64le->x86_64 cross to verify the correct type is now
chosen. Committed.
Thanks,
Bill
2016-12-05 Bill Schmidt <wschm...@linux.vnet.ibm.com>
Stefan Freudenberger <ste...@reservoir.com>
PR tree-optimization/78646
* gimple-ssa-strength-reduction.c (replace_ref): The pointer
addition used for the memory base expression should have the type
of the candidate.
Index: gcc/gimple-ssa-strength-reduction.c
===================================================================
--- gcc/gimple-ssa-strength-reduction.c (revision 243264)
+++ gcc/gimple-ssa-strength-reduction.c (working copy)
@@ -1921,7 +1921,7 @@ replace_ref (tree *expr, slsr_cand_t c)
if (align < TYPE_ALIGN (acc_type))
acc_type = build_aligned_type (acc_type, align);
- add_expr = fold_build2 (POINTER_PLUS_EXPR, TREE_TYPE (c->base_expr),
+ add_expr = fold_build2 (POINTER_PLUS_EXPR, c->cand_type,
c->base_expr, c->stride);
mem_ref = fold_build2 (MEM_REF, acc_type, add_expr,
wide_int_to_tree (c->cand_type, c->index));
