I am testing the following patch to restrict MEM canonicalization
in LIM further.
Bootstrap and regtest running on x86_64-unkown-linux-gnu.
Richard.
2019-01-30 Richard Biener <rguent...@suse.de>
PR tree-optimization/89111
* tree-ssa-loop-im.c (gather_mem_refs_stmt): Restrict
canonicalization to appropriately sized access types.
* gcc.dg/torture/pr89111.c: New testcase.
Index: gcc/tree-ssa-loop-im.c
===================================================================
--- gcc/tree-ssa-loop-im.c (revision 268383)
+++ gcc/tree-ssa-loop-im.c (working copy)
@@ -1472,6 +1472,11 @@ gather_mem_refs_stmt (struct loop *loop,
&& aor.max_size.is_constant (&max_size)
&& size == max_size
&& (size % BITS_PER_UNIT) == 0
+ /* We're canonicalizing to a MEM where TYPE_SIZE specifies the
+ size. Make sure this is consistent with the extraction. */
+ && poly_int_tree_p (TYPE_SIZE (TREE_TYPE (*mem)))
+ && known_eq (wi::to_poly_offset (TYPE_SIZE (TREE_TYPE (*mem))),
+ aor.size)
&& (mem_base = get_addr_base_and_unit_offset (aor.ref, &mem_off)))
{
hash = iterative_hash_expr (ao_ref_base (&aor), 0);
Index: gcc/testsuite/gcc.dg/torture/pr89111.c
===================================================================
--- gcc/testsuite/gcc.dg/torture/pr89111.c (nonexistent)
+++ gcc/testsuite/gcc.dg/torture/pr89111.c (working copy)
@@ -0,0 +1,30 @@
+/* { dg-do run } */
+/* { dg-require-effective-target int32plus } */
+
+struct __attribute__((packed)) A { int b : 24; } c[243], f;
+
+int d, e, g, j;
+
+__attribute__((noipa)) int
+foo (int x)
+{
+ if (x != 0)
+ __builtin_abort ();
+ return 2;
+}
+
+int
+main ()
+{
+ struct A h = f;
+ h.b = 0;
+ while (e++ < 3)
+ {
+ while (d++ < 3)
+ c[46].b ^= 9890739;
+ f = c[46] = h;
+ }
+ while (g++ < 9)
+ j = foo (c[g * 9 + j].b);
+ return 0;
+}
