On Tue, Jan 16, 2018 at 02:19:16PM +0100, Christophe Lyon wrote:
> I've noticed that this new test fails on arm, eg:
> arm-none-linux-gnueabihf
> --with-mode arm
> --with-cpu cortex-a9
> --with-fpu neon-fp16
> FAIL: gcc.dg/store_merging_18.c scan-tree-dump-times store-merging
> "Merging successful" 3 (found 0 times)
Ugh, the problem that arm announces itself as a store_merge target when
it can't do unaligned stores again, so essentially dup of PR83195.
We really shouldn't lie :(.
Anyway, for now I've checked in the following which matches what I've done
for PR83195.
Better would be to have store_merge_unaligned and store_merge, where
the former would be current store_merge except for arm, and latter
would be all targets that can perform store merging (isn't that all except
targets that don't have 8-bit chars or pdp endianity)?
2018-01-17 Jakub Jelinek <ja...@redhat.com>
PR tree-optimization/83843
* gcc.dg/store_merging_18.c: Don't expect "Merging successful" on arm.
* gcc.dg/store_merging_19.c: New test.
--- gcc/testsuite/gcc.dg/store_merging_18.c.jj 2018-01-16 09:52:26.231235131
+0100
+++ gcc/testsuite/gcc.dg/store_merging_18.c 2018-01-17 12:10:07.862957549
+0100
@@ -1,7 +1,7 @@
/* PR tree-optimization/83843 */
/* { dg-do run } */
/* { dg-options "-O2 -fdump-tree-store-merging" } */
-/* { dg-final { scan-tree-dump-times "Merging successful" 3 "store-merging" {
target store_merge } } } */
+/* { dg-final { scan-tree-dump-times "Merging successful" 3 "store-merging" {
target { store_merge && { ! arm*-*-* } } } } } */
__attribute__((noipa)) void
foo (unsigned char *buf, unsigned char *tab)
--- gcc/testsuite/gcc.dg/store_merging_19.c.jj 2018-01-17 12:10:34.819962003
+0100
+++ gcc/testsuite/gcc.dg/store_merging_19.c 2018-01-17 12:13:08.425987375
+0100
@@ -0,0 +1,57 @@
+/* PR tree-optimization/83843 */
+/* { dg-do run } */
+/* { dg-options "-O2 -fdump-tree-store-merging" } */
+/* { dg-final { scan-tree-dump-times "Merging successful" 3 "store-merging" {
target store_merge } } } */
+
+__attribute__((noipa)) void
+foo (unsigned char *buf, unsigned char *tab)
+{
+ tab = __builtin_assume_aligned (tab, 2);
+ buf = __builtin_assume_aligned (buf, 2);
+ unsigned v = tab[1] ^ (tab[0] << 8);
+ buf[0] = ~(v >> 8);
+ buf[1] = ~v;
+}
+
+__attribute__((noipa)) void
+bar (unsigned char *buf, unsigned char *tab)
+{
+ tab = __builtin_assume_aligned (tab, 2);
+ buf = __builtin_assume_aligned (buf, 2);
+ unsigned v = tab[1] ^ (tab[0] << 8);
+ buf[0] = (v >> 8);
+ buf[1] = ~v;
+}
+
+__attribute__((noipa)) void
+baz (unsigned char *buf, unsigned char *tab)
+{
+ tab = __builtin_assume_aligned (tab, 2);
+ buf = __builtin_assume_aligned (buf, 2);
+ unsigned v = tab[1] ^ (tab[0] << 8);
+ buf[0] = ~(v >> 8);
+ buf[1] = v;
+}
+
+int
+main ()
+{
+ volatile unsigned char l1 = 0;
+ volatile unsigned char l2 = 1;
+ unsigned char buf[2] __attribute__((aligned (2)));
+ unsigned char tab[2] __attribute__((aligned (2))) = { l1 + 1, l2 * 2 };
+ foo (buf, tab);
+ if (buf[0] != (unsigned char) ~1 || buf[1] != (unsigned char) ~2)
+ __builtin_abort ();
+ buf[0] = l1 + 7;
+ buf[1] = l2 * 8;
+ bar (buf, tab);
+ if (buf[0] != 1 || buf[1] != (unsigned char) ~2)
+ __builtin_abort ();
+ buf[0] = l1 + 9;
+ buf[1] = l2 * 10;
+ baz (buf, tab);
+ if (buf[0] != (unsigned char) ~1 || buf[1] != 2)
+ __builtin_abort ();
+ return 0;
+}
Jakub
