Make InToSpace/InFromSpace use the page header.

src/ia32/macro-assembler-ia32-inl.h

 // 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 40 matching lines @@
     test_b(Operand(scratch, MemoryChunk::kFlagsOffset),
            static_cast<uint8_t>(1u << flag));
   } else {
     test(Operand(scratch, MemoryChunk::kFlagsOffset), Immediate(1 << flag));
   }
   j(cc, condition_met);
 }
 
 
 template<typename LabelType>
+void MacroAssembler::InNewSpace(
+    Register object,
+    Register scratch,
+    Condition cc,
+    LabelType* condition_met) {
+  ASSERT(cc == equal || cc == not_equal);
+  if (scratch.is(object)) {
+    and_(scratch, Immediate(~Page::kPageAlignmentMask));
+  } else {
+    mov(scratch, Immediate(~Page::kPageAlignmentMask));
+    and_(scratch, Operand(object));
+  }
+  // Check that we can use a test_b.
+  ASSERT(MemoryChunk::IN_FROM_SPACE < 8);
+  ASSERT(MemoryChunk::IN_TO_SPACE < 8);
+  int mask = (1 << MemoryChunk::IN_FROM_SPACE)
+           | (1 << MemoryChunk::IN_TO_SPACE);
+  // If non-zero, the page belongs to new-space.
+  test_b(Operand(scratch, MemoryChunk::kFlagsOffset),
+         static_cast<uint8_t>(mask));
+  j(NegateCondition(cc), condition_met);
+}
+
+
+template<typename LabelType>
 void MacroAssembler::InOldSpaceIsBlack(Register object,
                                        Register scratch0,
                                        Register scratch1,
                                        LabelType* is_black) {
   HasColour(object, scratch0, scratch1,
             is_black,
             1, 0);  // kBlackBitPattern.
   ASSERT(strcmp(Marking::kBlackBitPattern, "10") == 0);
 }
 
@@ skipping 130 matching lines @@
 
   // Value is a data object, and it is white.  Mark it black.  Since we know
   // that the object is white we can make it black by flipping one bit.
   or_(Operand(bitmap_scratch, MemoryChunk::kHeaderSize), mask_scratch);
   bind(&done);
 }
 
 } }  // namespace v8::internal
 
 #endif  // V8_IA32_MACRO_ASSEMBLER_IA32_INL_H_