Use page header information to test for InNewSpace.

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

Index: src/ia32/macro-assembler-ia32-inl.h
diff --git a/src/ia32/macro-assembler-ia32-inl.h b/src/ia32/macro-assembler-ia32-inl.h
index 634a3e1e2ee7ae3ceac912b0ce92fa3d03cb2411..0bf1eb497c5ac8108f34664f013421248a7930d0 100644
--- a/src/ia32/macro-assembler-ia32-inl.h
+++ b/src/ia32/macro-assembler-ia32-inl.h
@@ -33,6 +33,25 @@
 namespace v8 {
 namespace internal {
 
+template <typename LabelType>
+void MacroAssembler::InNewSpace(Register object,

[Erik Corry, 2011/05/19 07:22:32]

Seems like you can just use CheckPageFlag instead of this having an
implementation.

[Lasse Reichstein, 2011/05/19 08:40:40]

Merged this with CheckPageFlag (accept object and scratch being the same
register, use byte test).

+                                Register scratch,
+                                Condition cc,
+                                LabelType* branch) {
+  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));
+  }
+  // Ensure that flag is in the first byte of flags field.
+  ASSERT(MemoryChunk::IN_NEW_SPACE < kBitsPerByte);
+  test_b(Operand(scratch, MemoryChunk::kFlagsOffset),
+         1 << MemoryChunk::IN_NEW_SPACE);
+  j(NegateCondition(cc), branch);
+}
+
 
 template<typename LabelType>
 void MacroAssembler::CheckPageFlag(