Provide baseline for experimental GC implementation.

src/arm/code-stubs-arm.cc

Index: src/arm/code-stubs-arm.cc
diff --git a/src/arm/code-stubs-arm.cc b/src/arm/code-stubs-arm.cc
index 3670765a61223bf20f6c5178edb1396cd3296dec..013c5a5f71bff926259d21d4cf6c0aec2e113ee1 100644
--- a/src/arm/code-stubs-arm.cc
+++ b/src/arm/code-stubs-arm.cc
@@ -918,8 +918,10 @@ void NumberToStringStub::Generate(MacroAssembler* masm) {
 
 
 void RecordWriteStub::Generate(MacroAssembler* masm) {
+#ifdef ENABLE_CARDMARKING_WRITE_BARRIER
   __ add(offset_, object_, Operand(offset_));
   __ RecordWriteHelper(object_, offset_, scratch_);
+#endif
   __ Ret();
 }
 
@@ -3420,12 +3422,16 @@ void RegExpExecStub::Generate(MacroAssembler* masm) {
   __ str(subject,
          FieldMemOperand(last_match_info_elements,
                          RegExpImpl::kLastSubjectOffset));
+#ifdef ENABLE_CARDMARKING_WRITE_BARRIER
   __ RecordWrite(r3, Operand(RegExpImpl::kLastSubjectOffset), r2, r7);
+#endif
   __ str(subject,
          FieldMemOperand(last_match_info_elements,
                          RegExpImpl::kLastInputOffset));
+#ifdef ENABLE_CARDMARKING_WRITE_BARRIER
   __ mov(r3, last_match_info_elements);
   __ RecordWrite(r3, Operand(RegExpImpl::kLastInputOffset), r2, r7);
+#endif
 
   // Get the static offsets vector filled by the native regexp code.
   ExternalReference address_of_static_offsets_vector =