Additional work to get array literal allocation tracking working, even with --always-opt

src/code-stubs.h

 // Copyright 2012 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
@@ skipping 409 matching lines @@
 
 class FastCloneShallowArrayStub : public PlatformCodeStub {
  public:
   // Maximum length of copied elements array.
   static const int kMaximumClonedLength = 8;
   enum Mode {
     CLONE_ELEMENTS,
     CLONE_DOUBLE_ELEMENTS,
     COPY_ON_WRITE_ELEMENTS,
     CLONE_ANY_ELEMENTS,
-    CLONE_ANY_ELEMENTS_WITH_ALLOCATION_SITE_INFO,
-    LAST_CLONE_MODE = CLONE_ANY_ELEMENTS_WITH_ALLOCATION_SITE_INFO
+    LAST_CLONE_MODE = CLONE_ANY_ELEMENTS
   };
 
   static const int kFastCloneModeCount = LAST_CLONE_MODE + 1;
 
-  FastCloneShallowArrayStub(Mode mode, int length)
+  FastCloneShallowArrayStub(Mode mode,
+                            AllocationSiteMode allocation_site_mode,
+                            int length)
       : mode_(mode),
+        allocation_site_mode_(allocation_site_mode),
         length_((mode == COPY_ON_WRITE_ELEMENTS) ? 0 : length) {
     ASSERT_GE(length_, 0);
     ASSERT_LE(length_, kMaximumClonedLength);
   }
 
   void Generate(MacroAssembler* masm);
 
  private:
   Mode mode_;
+  AllocationSiteMode allocation_site_mode_;
   int length_;
 
+  class AllocationSiteModeBits: public BitField<AllocationSiteMode, 0, 1> {};
+  class ModeBits: public BitField<Mode, 1, 4> {};
+  class LengthBits: public BitField<int, 5, 5> {};

[Toon Verwaest, 2013/01/16 13:35:55]

You only need 4 bits here.

[mvstanton, 2013/01/16 14:21:00]

Done.

+  STATIC_ASSERT(LAST_ALLOCATION_SITE_MODE == 1);
+  STATIC_ASSERT(kFastCloneModeCount <= 8);
+  STATIC_ASSERT(kMaximumClonedLength <= 8);

[Toon Verwaest, 2013/01/16 13:35:55]

With 4 bits, this field supports < 16.

[mvstanton, 2013/01/16 14:21:00]

Done.

   Major MajorKey() { return FastCloneShallowArray; }
   int MinorKey() {
-    ASSERT(mode_ >= 0 && mode_ <= LAST_CLONE_MODE);
-    return length_ * kFastCloneModeCount + mode_;
+    return AllocationSiteModeBits::encode(allocation_site_mode_)
+        | ModeBits::encode(mode_)
+        | LengthBits::encode(length_);
   }
 };
 
 
 class FastCloneShallowObjectStub : public PlatformCodeStub {
  public:
   // Maximum number of properties in copied object.
   static const int kMaximumClonedProperties = 6;
 
   explicit FastCloneShallowObjectStub(int length) : length_(length) {
@@ skipping 838 matching lines @@
 
   // The current function entry hook.
   static FunctionEntryHook entry_hook_;
 
   DISALLOW_COPY_AND_ASSIGN(ProfileEntryHookStub);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_CODE_STUBS_H_