2009-06-29 Richard Guenther <rguenther@suse.de>

	PR tree-optimization/40579
	* tree-vrp.c (vrp_evaluate_conditional): Bail out early if
	the IL to simplify has constants that overflowed.

	* gcc.c-torture/execute/pr40579.c: New testcase.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@149046 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index e6a5cea..13aeba0 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2009-06-29  Richard Guenther  <rguenther@suse.de>
+
+       PR tree-optimization/40579
+       * tree-vrp.c (vrp_evaluate_conditional): Bail out early if
+       the IL to simplify has constants that overflowed.
+
 2009-06-28  Uros Bizjak  <ubizjak@gmail.com>
 
        PR tree-optimization/40550

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 80fe78b..b819b37 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2009-06-29  Richard Guenther  <rguenther@suse.de>
+
+       PR tree-optimization/40579
+       * gcc.c-torture/execute/pr40579.c: New testcase.
+
 2009-06-28  Uros Bizjak  <ubizjak@gmail.com>
 
        PR tree-optimization/40550

diff --git a/gcc/testsuite/gcc.c-torture/execute/pr40579.c b/gcc/testsuite/gcc.c-torture/execute/pr40579.c
new file mode 100644 (file)
index 0000000..7f44af3
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr40579.c
@@ -0,0 +1,28 @@
+extern void abort (void);
+static char * __attribute__((noinline))
+itos(int num)
+{
+  return (char *)0;
+}
+static void __attribute__((noinline))
+foo(int i, const char *x)
+{
+  if (i >= 4)
+    abort ();
+}
+int main()
+{
+  int x = -__INT_MAX__ + 3;
+  int i;
+
+  for (i = 0; i < 4; ++i)
+    {
+      char *p;
+      --x;
+      p = itos(x);
+      foo(i, p);
+    }
+
+  return 0;
+}
+

diff --git a/gcc/tree-vrp.c b/gcc/tree-vrp.c
index 41a1beb..13ed4c0 100644 (file)
--- a/gcc/tree-vrp.c
+++ b/gcc/tree-vrp.c
@@ -5679,6 +5679,14 @@ vrp_evaluate_conditional (enum tree_code code, tree op0, tree op1, gimple stmt)
   tree ret;
   bool only_ranges;
 
+  /* Some passes and foldings leak constants with overflow flag set
+     into the IL.  Avoid doing wrong things with these and bail out.  */
+  if ((TREE_CODE (op0) == INTEGER_CST
+       && TREE_OVERFLOW (op0))
+      || (TREE_CODE (op1) == INTEGER_CST
+         && TREE_OVERFLOW (op1)))
+    return NULL_TREE;
+
   sop = false;
   ret = vrp_evaluate_conditional_warnv_with_ops (code, op0, op1, true, &sop,
                                                 &only_ranges);