Revert "GVN fix, preventing loads hoisting above stores to the same field when HObjec...

This reverts commit r21830 for tanking performance on Deltablue.

TBR=ishell@chromium.org

Review URL: https://codereview.chromium.org/336223002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@21857 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/hydrogen-gvn.cc b/src/hydrogen-gvn.cc
index 385947d..e6f1ae9 100644 (file)
--- a/src/hydrogen-gvn.cc
+++ b/src/hydrogen-gvn.cc
@@ -466,7 +466,7 @@ bool SideEffectsTracker::ComputeGlobalVar(Unique<Cell> cell, int* index) {
 bool SideEffectsTracker::ComputeInobjectField(HObjectAccess access,
                                               int* index) {
   for (int i = 0; i < num_inobject_fields_; ++i) {
-    if (access.SameField(inobject_fields_[i])) {
+    if (access.Equals(inobject_fields_[i])) {
       *index = i;
       return true;
     }

diff --git a/src/hydrogen-instructions.h b/src/hydrogen-instructions.h
index fce5d68..f1720f4 100644 (file)
--- a/src/hydrogen-instructions.h
+++ b/src/hydrogen-instructions.h
@@ -6202,14 +6202,7 @@ class HObjectAccess V8_FINAL {
   void PrintTo(StringStream* stream) const;
 
   inline bool Equals(HObjectAccess that) const {
-    return value_ == that.value_;
-  }
-
-  // Returns true if |this| access refers to the same field as |that|, which
-  // means that both have same |offset| and |portion| values.
-  inline bool SameField(HObjectAccess that) const {
-    uint32_t mask = PortionField::kMask | OffsetField::kMask;
-    return (value_ & mask) == (that.value_ & mask);
+    return value_ == that.value_;  // portion and offset must match
   }
 
  protected:

diff --git a/test/mjsunit/regress/regress-gvn-ftt.js b/test/mjsunit/regress/regress-gvn-ftt.js
deleted file mode 100644 (file)
index d2cb443..0000000
--- a/test/mjsunit/regress/regress-gvn-ftt.js
+++ /dev/null
@@ -1,27 +0,0 @@
-// Copyright 2014 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.
-
-// Flags: --allow-natives-syntax --track-field-types --use-gvn
-
-function A(id) {
-  this.id = id;
-}
-
-var a1 = new A(1);
-var a2 = new A(2);
-
-
-var g;
-function f(o, value) {
-  g = o.o;
-  o.o = value;
-  return o.o;
-}
-
-var obj = {o: a1};
-
-f(obj, a1);
-f(obj, a1);
-%OptimizeFunctionOnNextCall(f);
-assertEquals(a2.id, f(obj, a2).id);