Fix a bug in graph construction for for loops.

tests/language/for_test.dart

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 // Dart test program for testing for statement.
 
 import "package:expect/expect.dart";
 
 class Helper {
   static int f1() {
     for (;;) return 1;
@@ skipping 13 matching lines @@
 
   static int f4(n) {
     int i = 0;
     for (bool stop = false; (i < n) && !stop; i++) {
       if (i >= 5) {
         stop = true;
       }
     }
     return i;
   }
+
+  static var status;
+  static void f5() {
+    status = 0;
+    for (var stop = false;;) {
+      if (stop) {
+        break;
+      } else {
+        stop = true;
+        continue;
+      }
+    }

[filemon, 2013/06/20 10:37:01]

Does this test fail before patching?

I mean, with the bug, the code in attachment (of issue below) always breaks from
loop, and status would be equal 1.

https://code.google.com/p/dart/issues/detail?id=11375

[Kevin Millikin (Google), 2013/06/20 10:48:45]

Yeah, it crashes without the fix.

We should really have exhaustive tests of all for loops:

* with and without initializer
* with and without test
* with and without update
* with and without normal exit from the body
* with and without break
* with and without continue

That's 64 possibilities.

[filemon, 2013/06/27 11:44:06]

Hi, I wrote a simple script to generate loops:
https://gist.github.com/orian/5875825

It needs some adjustment, what do you think?

On 2013/06/20 10:48:45, kmillikin wrote:

+    status = 1;
+  }
 }
 
 class ForTest {
   static testMain() {
     Expect.equals(1, Helper.f1());
     Expect.equals(0, Helper.f2(-1));
     Expect.equals(0, Helper.f2(0));
     Expect.equals(10, Helper.f2(10));
     Expect.equals(0, Helper.f3(-1));
     Expect.equals(0, Helper.f3(0));
     Expect.equals(1, Helper.f3(1));
     Expect.equals(3, Helper.f3(2));
     Expect.equals(6, Helper.f3(3));
     Expect.equals(10, Helper.f3(4));
     Expect.equals(0, Helper.f4(-1));
     Expect.equals(0, Helper.f4(0));
     Expect.equals(1, Helper.f4(1));
     Expect.equals(6, Helper.f4(6));
     Expect.equals(6, Helper.f4(10));
+
+    Helper.f5();
+    Expect.equals(1, Helper.status);
   }
 }
 
 main() {
   ForTest.testMain();
 }