Basic support for tracking smi-only arrays on ia32.

src/ia32/macro-assembler-ia32.cc

Index: src/ia32/macro-assembler-ia32.cc
diff --git a/src/ia32/macro-assembler-ia32.cc b/src/ia32/macro-assembler-ia32.cc
index 837112a55c8993c84608274c95316dd855d7d873..1bc20b4f8c5a3a99a86bd98938d27549aaa63ee9 100644
--- a/src/ia32/macro-assembler-ia32.cc
+++ b/src/ia32/macro-assembler-ia32.cc
@@ -287,13 +287,38 @@ void MacroAssembler::CmpInstanceType(Register map, InstanceType type) {
 void MacroAssembler::CheckFastElements(Register map,
                                        Label* fail,
                                        Label::Distance distance) {
-  STATIC_ASSERT(FAST_ELEMENTS == 0);
+  STATIC_ASSERT(FAST_SMI_ONLY_ELEMENTS == 0);
+  STATIC_ASSERT(FAST_ELEMENTS == 1);
   cmpb(FieldOperand(map, Map::kBitField2Offset),
        Map::kMaximumBitField2FastElementValue);
   j(above, fail, distance);
 }
 
 
+void MacroAssembler::CheckFastObjectElements(Register map,
+                                             Label* fail,
+                                             Label::Distance distance) {
+  STATIC_ASSERT(FAST_SMI_ONLY_ELEMENTS == 0);
+  STATIC_ASSERT(FAST_ELEMENTS == 1);
+  cmpb(FieldOperand(map, Map::kBitField2Offset),
+       Map::kMaximumBitField2FastSmiOnlyElementValue);
+  j(below_equal, fail, distance);
+  cmpb(FieldOperand(map, Map::kBitField2Offset),
+       Map::kMaximumBitField2FastElementValue);
+  j(above, fail, distance);
+}
+
+
+void MacroAssembler::CheckFastSmiOnlyElements(Register map,
+                                              Label* fail,
+                                              Label::Distance distance) {
+  STATIC_ASSERT(FAST_SMI_ONLY_ELEMENTS == 0);
+  cmpb(FieldOperand(map, Map::kBitField2Offset),
+       Map::kMaximumBitField2FastSmiOnlyElementValue);
+  j(above, fail, distance);
+}
+
+
 void MacroAssembler::CheckMap(Register obj,
                               Handle<Map> map,
                               Label* fail,