Merge bleeding edge up to 8774 into the GC branch.

src/x64/macro-assembler-x64.cc

 // Copyright 2011 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 386 matching lines @@
 }
 
 
 void MacroAssembler::AssertFastElements(Register elements) {
   if (emit_debug_code()) {
     Label ok;
     CompareRoot(FieldOperand(elements, HeapObject::kMapOffset),
                 Heap::kFixedArrayMapRootIndex);
     j(equal, &ok, Label::kNear);
     CompareRoot(FieldOperand(elements, HeapObject::kMapOffset),
+                Heap::kFixedDoubleArrayMapRootIndex);
+    j(equal, &ok, Label::kNear);
+    CompareRoot(FieldOperand(elements, HeapObject::kMapOffset),
                 Heap::kFixedCOWArrayMapRootIndex);
     j(equal, &ok, Label::kNear);
     Abort("JSObject with fast elements map has slow elements");
     bind(&ok);
   }
 }
 
 
 void MacroAssembler::Check(Condition cc, const char* msg) {
   Label L;
@@ skipping 3603 matching lines @@
   movq(rcx, addr_reg);
   shrl(rcx, Immediate(kPointerSizeLog2));
   and_(rcx, Immediate((1 << Bitmap::kBitsPerCellLog2) - 1));
   movl(mask_reg, Immediate(1));
   shl_cl(mask_reg);
 }
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64