re PR tree-optimization/33593 (tree-outof-ssa moves sources of non-call…

re PR tree-optimization/33593 (tree-outof-ssa moves sources of non-call exceptions past sequence points)


	PR 33593
	* tree-ssa-ter.c (is_replaceable_p): Return false if STMT may
	throw an exception.


testsuite/ChangeLog

	PR 33593
	* g++.dg/tree-ssa/pr33593.C: New test.

From-SVN: r128893

gcc/ChangeLog

+2007-09-30  Diego Novillo  <dnovillo@google.com>
+
+	PR 33593
+	* tree-ssa-ter.c (is_replaceable_p): Return false if STMT may
+	throw an exception.
+
 2007-09-30  Uros Bizjak  <ubizjak@gmail.com>
 
 	PR tree-optimization/33597

gcc/testsuite/ChangeLog

+2007-09-30  Diego Novillo  <dnovillo@google.com>
+
+	PR 33593
+	* g++.dg/tree-ssa/pr33593.C: New test.
+
 2007-09-30  Jerry DeLisle  <jvdelisle@gcc.gnu.org>
 
 	PR libfortran/33400

gcc/testsuite/g++.dg/tree-ssa/pr33593.C

+/* { dg-do compile } */
+/* { dg-options "-O1 -fnon-call-exceptions -fdump-tree-optimized" } */
+
+#include <stdio.h>
+
+void foo (int) { printf ("Bar\n"); }
+
+int
+main (void)
+{
+  int a = 1 / 0;	// { dg-warning "division by zero" }
+  printf ("Foo\n");
+  foo (a);
+}
+
+// The expression 1 / 0 should not be propagated into the call to foo() if it
+// may trap.
+// { dg-final { scan-tree-dump-times "foo \\(1 \\/ 0\\)" 0 "optimized" } }
+// { dg-final { cleanup-tree-dump "optimized" } }

gcc/tree-ssa-ter.c

@@ -366,6 +366,10 @@ is_replaceable_p (tree stmt)
   if (TREE_CODE (stmt) != GIMPLE_MODIFY_STMT)
     return false;
 
+  /* If the statement may throw an exception, it cannot be replaced.  */
+  if (tree_could_throw_p (stmt))
+    return false;
+
   /* Punt if there is more than 1 def.  */
   def = SINGLE_SSA_TREE_OPERAND (stmt, SSA_OP_DEF);
   if (!def)