[10/9] Add tests for stride-3 accesses

[Richard Sandiford <richard.sandiford@linaro.org>]

This patch adds a test for stride-3 accesses.  I didn't add any
particularly complicated cases because I think the testsuite already
covers the interaction between the strided loads & stores and other
operations pretty well.  Let me know if there's something I should
add though.

Tested on x86_64-linux-gnu and arm-linux-gnueabi.  OK to install?

Richard


gcc/testsuite/
	* gcc.dg/vect/vect-strided-u16-i3.c: New test.

Index: gcc/testsuite/gcc.dg/vect/vect-strided-u16-i3.c
===================================================================
--- /dev/null	2011-03-23 08:42:11.268792848 +0000
+++ gcc/testsuite/gcc.dg/vect/vect-strided-u16-i3.c	2011-04-12 11:55:17.000000000 +0100
@@ -0,0 +1,112 @@
+#include <stdarg.h>
+#include "tree-vect.h"
+
+#define N 128
+
+typedef struct {
+   unsigned short a;
+   unsigned short b;
+   unsigned short c;
+} s;
+
+#define A(I) (I)
+#define B(I) ((I) * 2)
+#define C(I) ((unsigned short) ~((I) ^ 0x18))
+
+void __attribute__ ((noinline))
+check1 (s *res)
+{
+  int i;
+
+  for (i = 0; i < N; i++)
+    if (res[i].a != C (i)
+	|| res[i].b != A (i)
+	|| res[i].c != B (i))
+      abort ();
+}
+
+void __attribute__ ((noinline))
+check2 (unsigned short *res)
+{
+  int i;
+
+  for (i = 0; i < N; i++)
+    if (res[i] != (unsigned short) (A (i) + B (i) + C (i)))
+      abort ();
+}
+
+void __attribute__ ((noinline))
+check3 (s *res)
+{
+  int i;
+
+  for (i = 0; i < N; i++)
+    if (res[i].a != i
+	|| res[i].b != i
+	|| res[i].c != i)
+      abort ();
+}
+
+void __attribute__ ((noinline))
+check4 (unsigned short *res)
+{
+  int i;
+
+  for (i = 0; i < N; i++)
+    if (res[i] != (unsigned short) (A (i) + B (i)))
+      abort ();
+}
+
+void __attribute__ ((noinline))
+main1 (s *arr)
+{
+  int i;
+  s *ptr = arr;
+  s res1[N];
+  unsigned short res2[N];
+
+  for (i = 0; i < N; i++)
+    {
+      res1[i].a = arr[i].c;
+      res1[i].b = arr[i].a;
+      res1[i].c = arr[i].b;
+    }
+  check1 (res1);
+
+  for (i = 0; i < N; i++)
+    res2[i] = arr[i].a + arr[i].b + arr[i].c;
+  check2 (res2);
+
+  for (i = 0; i < N; i++)
+    {
+      res1[i].a = i;
+      res1[i].b = i;
+      res1[i].c = i;
+    }
+  check3 (res1);
+
+  for (i = 0; i < N; i++)
+    res2[i] = arr[i].a + arr[i].b;
+  check4 (res2);
+}
+
+int main (void)
+{
+  int i;
+  s arr[N];
+
+  check_vect ();
+
+  for (i = 0; i < N; i++)
+    {
+      arr[i].a = A (i);
+      arr[i].b = B (i);
+      arr[i].c = C (i);
+    }
+  main1 (arr);
+
+  return 0;
+}
+
+/* { dg-final { scan-tree-dump-times "vectorized 4 loops" 1 "vect"  { target vect_strided3 } } } */
+/* { dg-final { cleanup-tree-dump "vect" } } */