obtained gcc-4.6.4.tar.bz2 from upstream website;upstream

verified gcc-4.6.4.tar.bz2.sig;
imported gcc-4.6.4 source tree from verified upstream tarball.

downloading a git-generated archive based on the 'upstream' tag
should provide you with a source tree that is binary identical
to the one extracted from the above tarball.

if you have obtained the source via the command 'git clone',
however, do note that line-endings of files in your working
directory might differ from line-endings of the respective
files in the upstream repository.

1 files changed, 50 insertions, 0 deletions

diff --git a/gcc/testsuite/gcc.c-torture/execute/loop-ivopts-2.c b/gcc/testsuite/gcc.c-torture/execute/loop-ivopts-2.c
new file mode 100644
index 000000000..737640bff
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/loop-ivopts-2.c
@@ -0,0 +1,50 @@
+/* PR rtl-optimization/20290  */
+   
+/* We used to mis-optimize the second loop in main on at least ppc and
+   arm, because tree loop would change the loop to something like:
+
+  ivtmp.65 = &l[i];
+  ivtmp.16 = 113;
+  goto <bb 4> (<L4>);
+
+<L3>:;
+  *(ivtmp.65 + 4294967292B) = 9;
+  i = i + 1;
+
+<L4>:;
+  ivtmp.16 = ivtmp.16 - 1;
+  ivtmp.65 = ivtmp.65 + 4B;
+  if (ivtmp.16 != 0) goto <L3>; 
+
+  We used to consider the increment of i as executed in every
+  iteration, so we'd miscompute the final value.  */
+
+extern void abort (void);
+
+void
+check (unsigned int *l)
+{
+  int i;
+  for (i = 0; i < 288; i++)
+    if (l[i] != 7 + (i < 256 || i >= 280) + (i >= 144 && i < 256))
+      abort ();
+}
+
+int
+main (void)
+{
+  int i;
+  unsigned int l[288];
+
+  for (i = 0; i < 144; i++)
+    l[i] = 8;
+  for (; i < 256; i++)
+    l[i] = 9;
+  for (; i < 280; i++)
+    l[i] = 7;
+  for (; i < 288; i++)
+    l[i] = 8;
+  check (l);
+  return 0;
+}
+