We don't support vectorizing group stores with gaps - so the natural
thing is to just split groups at such boundaries which enables
more BB vectorization (and likely loop vectorization as well, though
that would be some weird cases I suspect).
Bootstrap and regtest running on x86_64-unknown-linux-gnu.
Richard.
2015-05-04 Richard Biener <rguent...@suse.de>
PR tree-optimization/65965
* tree-vect-data-refs.c (vect_analyze_data_ref_accesses): Split
store groups at gaps.
* gcc.dg/vect/bb-slp-33.c: New testcase.
Index: gcc/tree-vect-data-refs.c
===================================================================
--- gcc/tree-vect-data-refs.c (revision 222758)
+++ gcc/tree-vect-data-refs.c (working copy)
@@ -2602,6 +2602,15 @@ vect_analyze_data_ref_accesses (loop_vec
if ((init_b - init_a) % type_size_a != 0)
break;
+ /* If we have a store, the accesses are adjacent. This splits
+ groups into chunks we support (we don't support vectorization
+ of stores with gaps). */
+ if (!DR_IS_READ (dra)
+ && (((unsigned HOST_WIDE_INT)init_b
+ - TREE_INT_CST_LOW (DR_INIT (datarefs_copy[i-1])))
+ != type_size_a))
+ break;
+
/* The step (if not zero) is greater than the difference between
data-refs' inits. This splits groups into suitable sizes. */
HOST_WIDE_INT step = tree_to_shwi (DR_STEP (dra));
Index: gcc/testsuite/gcc.dg/vect/bb-slp-33.c
===================================================================
--- gcc/testsuite/gcc.dg/vect/bb-slp-33.c (revision 0)
+++ gcc/testsuite/gcc.dg/vect/bb-slp-33.c (working copy)
@@ -0,0 +1,49 @@
+/* { dg-require-effective-target vect_int } */
+
+#include "tree-vect.h"
+
+extern void abort (void);
+
+void __attribute__((noinline,noclone))
+test(int *__restrict__ a, int *__restrict__ b)
+{
+ a[0] = b[0];
+ a[1] = b[1];
+ a[2] = b[2];
+ a[3] = b[3];
+ a[5] = 0;
+ a[6] = 0;
+ a[7] = 0;
+ a[8] = 0;
+}
+
+int main()
+{
+ int a[9];
+ int b[4];
+ b[0] = 1;
+ __asm__ volatile ("");
+ b[1] = 2;
+ __asm__ volatile ("");
+ b[2] = 3;
+ __asm__ volatile ("");
+ b[3] = 4;
+ __asm__ volatile ("");
+ a[4] = 7;
+ check_vect ();
+ test(a, b);
+ if (a[0] != 1
+ || a[1] != 2
+ || a[2] != 3
+ || a[3] != 4
+ || a[4] != 7
+ || a[5] != 0
+ || a[6] != 0
+ || a[7] != 0
+ || a[8] != 0)
+ abort ();
+ return 0;
+}
+
+/* { dg-final { scan-tree-dump-times "vectorizing stmts using SLP" 2 "slp2" {
target { vect_element_align || vect_hw_misalign } } } } */
+/* { dg-final { cleanup-tree-dump "slp2" } } */
