Collect side effects on paths to dominated block including the dominator.

BUG=
R=danno@chromium.org

Review URL: https://codereview.chromium.org/18254008

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@15649 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/hydrogen-gvn.cc b/src/hydrogen-gvn.cc
index 12c536ad598978645653d35169b499dac76adfd5..4a946ea221599ec7225659add40a580a4f9831be 100644 (file)
--- a/src/hydrogen-gvn.cc
+++ b/src/hydrogen-gvn.cc
@@ -619,7 +619,7 @@ HGlobalValueNumberingPhase::CollectSideEffectsOnPathsToDominatedBlock(
   GVNFlagSet side_effects;
   for (int i = 0; i < dominated->predecessors()->length(); ++i) {
     HBasicBlock* block = dominated->predecessors()->at(i);
-    if (dominator->block_id() < block->block_id() &&
+    if (dominator->block_id() <= block->block_id() &&
         block->block_id() < dominated->block_id() &&
         visited_on_paths_.Add(block->block_id())) {
       side_effects.Add(block_side_effects_[block->block_id()]);

diff --git a/test/mjsunit/allocation-folding.js b/test/mjsunit/allocation-folding.js
new file mode 100644 (file)
index 0000000..a730bf1
--- /dev/null
+++ b/test/mjsunit/allocation-folding.js
@@ -0,0 +1,46 @@
+// Copyright 2013 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Flags: --allow-natives-syntax --nouse-osr
+function f() {
+  var elem1 = [1,2,3];
+  for (var i=0; i < 100000; i++) {
+    var bar = [1];
+  }
+  var elem2 = [1,2,3];
+  return elem2;
+}
+
+f(); f(); f();
+%OptimizeFunctionOnNextCall(f);
+var result = f();
+
+for (var i=0; i < 100000; i++) {
+  var bar = [1];
+}
+
+assertEquals(result[2], 3);