Version 3.28.71.9 (merged r23691)

src/hydrogen.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/hydrogen.h"
 
 #include <algorithm>
 
 #include "src/v8.h"
 
@@ skipping 8782 matching lines @@
   } else {
     DCHECK_EQ(kLastIndexOf, mode);
     initial = length;
     terminating = graph()->GetConstant0();
     token = Token::GT;
     direction = LoopBuilder::kPreDecrement;
   }
 
   Push(graph()->GetConstantMinus1());
   if (IsFastDoubleElementsKind(kind) || IsFastSmiElementsKind(kind)) {
+    // Make sure that we can actually compare numbers correctly below, see
+    // https://code.google.com/p/chromium/issues/detail?id=407946 for details.
+    search_element = AddUncasted<HForceRepresentation>(
+        search_element, IsFastSmiElementsKind(kind) ? Representation::Smi()
+                                                    : Representation::Double());
+
     LoopBuilder loop(this, context(), direction);
     {
       HValue* index = loop.BeginBody(initial, terminating, token);
       HValue* element = AddUncasted<HLoadKeyed>(
           elements, index, static_cast<HValue*>(NULL),
           kind, ALLOW_RETURN_HOLE);
       IfBuilder if_issame(this);
-      if (IsFastDoubleElementsKind(kind)) {
-        if_issame.If<HCompareNumericAndBranch>(
-            element, search_element, Token::EQ_STRICT);
-      } else {
-        if_issame.If<HCompareObjectEqAndBranch>(element, search_element);
-      }
+      if_issame.If<HCompareNumericAndBranch>(element, search_element,
+                                             Token::EQ_STRICT);
       if_issame.Then();
       {
         Drop(1);
         Push(index);
         loop.Break();
       }
       if_issame.End();
     }
     loop.EndBody();
   } else {
@@ skipping 3655 matching lines @@
   if (ShouldProduceTraceOutput()) {
     isolate()->GetHTracer()->TraceHydrogen(name(), graph_);
   }
 
 #ifdef DEBUG
   graph_->Verify(false);  // No full verify.
 #endif
 }
 
 } }  // namespace v8::internal