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, 51 insertions, 0 deletions

diff --git a/gcc/testsuite/g++.dg/opt/strength-reduce.C b/gcc/testsuite/g++.dg/opt/strength-reduce.C
new file mode 100644
index 000000000..3fee937f1
--- /dev/null
+++ b/gcc/testsuite/g++.dg/opt/strength-reduce.C
@@ -0,0 +1,51 @@
+// This testcase was miscompiled on s390x, because strength-reduction
+// did not see biv in C::foo as used after loop, but it was used
+// in a REG_EQUAL note.
+// { dg-do run }
+// { dg-options "-O2" }
+
+extern "C" void abort (void);
+
+struct C
+{
+  int foo (char ch, int offset = __INT_MAX__) const;
+  int bar (int offset, char c) const;
+   const char *a;
+};
+
+int C::bar (int offset, char c) const
+{
+  char ch = a[offset];
+  if (ch < c)
+    return -1;
+  if (ch > c)
+    return 1;
+  return 0;
+}
+
+int C::foo (char ch, int offset) const
+{
+  int len = __builtin_strlen (a);
+  if (len == 0)
+    return __INT_MAX__;
+  if (offset >= len)
+    offset = len - 1;
+
+  while (bar (offset, ch) != 0)
+    {
+      if (offset == 0)
+        return __INT_MAX__;
+      offset--;
+    }
+
+  return offset;
+}
+
+int main (void)
+{
+  C c;
+  c.a = "/some/dir/file.ext";
+  if (c.foo ('/') != 9)
+    abort ();
+  return 0;
+}