http://gcc.gnu.org/ml/gcc-patches/2008-01/msg00764.html

Teach SCCVN that throwing expressions are not to be regenerated.

2008-01-17  Andrew MacLeod  <amacleod@redhat.com>

	* tree-ssa-sccvn.c (visit_use): Expressions which can throw are varying.	* gcc.c-torture/compile/pr34648.c: New testcase.




git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@131610 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 39 insertions, 0 deletions

diff --git a/gcc/testsuite/gcc.c-torture/compile/pr34648.c b/gcc/testsuite/gcc.c-torture/compile/pr34648.c
new file mode 100644
index 00000000000..1f7472fe76d
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/compile/pr34648.c
@@ -0,0 +1,39 @@
+/* PR tree-optimization/34648 */
+
+/* { dg-do compile } */
+/* { dg-options "-O2 -fexceptions" } */
+
+extern const unsigned short int **bar (void) __attribute__ ((const));
+const char *a;
+int b;
+char c;
+
+char
+foo (int *x)
+{
+  char r;
+
+  c = '\0';
+  if (!b)
+    {
+      while (((*bar ())[a[*x]] & 0x2000) != 0)
+        (*x)++;
+      if (a[++(*x)] == '-')
+        {
+          (*x)++;
+          if (a[*x] && !((*bar ())[a[*x]] & 0x2000))
+            return '?';
+        }
+      if (!a[*x] || ((*bar ())[a[*x]] & 0x2000))
+        {
+          while (((*bar ())[a[*x]] & 0x2000))
+            ++(*x);
+          return '\0';
+        }
+    }
+
+  r = a[*x];
+  b = a[*x] && !((*bar ())[a[*x]] & 0x2000);
+  return r;
+}
+