Rollback of r11638, r11636 on trunk branch.

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 1b614867cd4a1bfa29efda6623fd41cc5bece440..c31b0c24bef9e63fc15793c278349549ca4510dd 100644
--- a/src/ia32/macro-assembler-ia32.cc
+++ b/src/ia32/macro-assembler-ia32.cc
@@ -382,12 +382,10 @@ void MacroAssembler::CmpInstanceType(Register map, InstanceType type) {
 void MacroAssembler::CheckFastElements(Register map,
                                        Label* fail,
                                        Label::Distance distance) {
-  STATIC_ASSERT(FAST_SMI_ELEMENTS == 0);
-  STATIC_ASSERT(FAST_HOLEY_SMI_ELEMENTS == 1);
-  STATIC_ASSERT(FAST_ELEMENTS == 2);
-  STATIC_ASSERT(FAST_HOLEY_ELEMENTS == 3);
+  STATIC_ASSERT(FAST_SMI_ONLY_ELEMENTS == 0);
+  STATIC_ASSERT(FAST_ELEMENTS == 1);
   cmpb(FieldOperand(map, Map::kBitField2Offset),
-       Map::kMaximumBitField2FastHoleyElementValue);
+       Map::kMaximumBitField2FastElementValue);
   j(above, fail, distance);
 }
 
@@ -395,26 +393,23 @@ void MacroAssembler::CheckFastElements(Register map,
 void MacroAssembler::CheckFastObjectElements(Register map,
                                              Label* fail,
                                              Label::Distance distance) {
-  STATIC_ASSERT(FAST_SMI_ELEMENTS == 0);
-  STATIC_ASSERT(FAST_HOLEY_SMI_ELEMENTS == 1);
-  STATIC_ASSERT(FAST_ELEMENTS == 2);
-  STATIC_ASSERT(FAST_HOLEY_ELEMENTS == 3);
+  STATIC_ASSERT(FAST_SMI_ONLY_ELEMENTS == 0);
+  STATIC_ASSERT(FAST_ELEMENTS == 1);
   cmpb(FieldOperand(map, Map::kBitField2Offset),
-       Map::kMaximumBitField2FastHoleySmiElementValue);
+       Map::kMaximumBitField2FastSmiOnlyElementValue);
   j(below_equal, fail, distance);
   cmpb(FieldOperand(map, Map::kBitField2Offset),
-       Map::kMaximumBitField2FastHoleyElementValue);
+       Map::kMaximumBitField2FastElementValue);
   j(above, fail, distance);
 }
 
 
-void MacroAssembler::CheckFastSmiElements(Register map,
-                                          Label* fail,
-                                          Label::Distance distance) {
-  STATIC_ASSERT(FAST_SMI_ELEMENTS == 0);
-  STATIC_ASSERT(FAST_HOLEY_SMI_ELEMENTS == 1);
+void MacroAssembler::CheckFastSmiOnlyElements(Register map,
+                                              Label* fail,
+                                              Label::Distance distance) {
+  STATIC_ASSERT(FAST_SMI_ONLY_ELEMENTS == 0);
   cmpb(FieldOperand(map, Map::kBitField2Offset),
-       Map::kMaximumBitField2FastHoleySmiElementValue);
+       Map::kMaximumBitField2FastSmiOnlyElementValue);
   j(above, fail, distance);
 }
 
@@ -498,18 +493,24 @@ void MacroAssembler::CompareMap(Register obj,
                                 CompareMapMode mode) {
   cmp(FieldOperand(obj, HeapObject::kMapOffset), map);
   if (mode == ALLOW_ELEMENT_TRANSITION_MAPS) {
-    ElementsKind kind = map->elements_kind();
-    if (IsFastElementsKind(kind)) {
-      bool packed = IsFastPackedElementsKind(kind);
-      Map* current_map = *map;
-      while (CanTransitionToMoreGeneralFastElementsKind(kind, packed)) {
-        kind = GetNextMoreGeneralFastElementsKind(kind, packed);
-        current_map = current_map->LookupElementsTransitionMap(kind, NULL);
-        if (!current_map) break;
-        j(equal, early_success, Label::kNear);
-        cmp(FieldOperand(obj, HeapObject::kMapOffset),
-            Handle<Map>(current_map));
-      }
+    Map* transitioned_fast_element_map(
+        map->LookupElementsTransitionMap(FAST_ELEMENTS, NULL));
+    ASSERT(transitioned_fast_element_map == NULL ||
+           map->elements_kind() != FAST_ELEMENTS);
+    if (transitioned_fast_element_map != NULL) {
+      j(equal, early_success, Label::kNear);
+      cmp(FieldOperand(obj, HeapObject::kMapOffset),
+          Handle<Map>(transitioned_fast_element_map));
+    }
+
+    Map* transitioned_double_map(
+        map->LookupElementsTransitionMap(FAST_DOUBLE_ELEMENTS, NULL));
+    ASSERT(transitioned_double_map == NULL ||
+           map->elements_kind() == FAST_SMI_ONLY_ELEMENTS);
+    if (transitioned_double_map != NULL) {
+      j(equal, early_success, Label::kNear);
+      cmp(FieldOperand(obj, HeapObject::kMapOffset),
+          Handle<Map>(transitioned_double_map));
     }
   }
 }
@@ -2160,38 +2161,27 @@ void MacroAssembler::LoadTransitionedArrayMapConditional(
   mov(scratch, FieldOperand(scratch, GlobalObject::kGlobalContextOffset));
 
   // Check that the function's map is the same as the expected cached map.
-  mov(scratch, Operand(scratch,
-                       Context::SlotOffset(Context::JS_ARRAY_MAPS_INDEX)));
-
-  size_t offset = expected_kind * kPointerSize +
-      FixedArrayBase::kHeaderSize;
-  cmp(map_in_out, FieldOperand(scratch, offset));
+  int expected_index =
+      Context::GetContextMapIndexFromElementsKind(expected_kind);
+  cmp(map_in_out, Operand(scratch, Context::SlotOffset(expected_index)));
   j(not_equal, no_map_match);
 
   // Use the transitioned cached map.
-  offset = transitioned_kind * kPointerSize +
-      FixedArrayBase::kHeaderSize;
-  mov(map_in_out, FieldOperand(scratch, offset));
+  int trans_index =
+      Context::GetContextMapIndexFromElementsKind(transitioned_kind);
+  mov(map_in_out, Operand(scratch, Context::SlotOffset(trans_index)));
 }
 
 
 void MacroAssembler::LoadInitialArrayMap(
-    Register function_in, Register scratch,
-    Register map_out, bool can_have_holes) {
+    Register function_in, Register scratch, Register map_out) {
   ASSERT(!function_in.is(map_out));
   Label done;
   mov(map_out, FieldOperand(function_in,
                             JSFunction::kPrototypeOrInitialMapOffset));
   if (!FLAG_smi_only_arrays) {
-    ElementsKind kind = can_have_holes ? FAST_HOLEY_ELEMENTS : FAST_ELEMENTS;
-    LoadTransitionedArrayMapConditional(FAST_SMI_ELEMENTS,
-                                        kind,
-                                        map_out,
-                                        scratch,
-                                        &done);
-  } else if (can_have_holes) {
-    LoadTransitionedArrayMapConditional(FAST_SMI_ELEMENTS,
-                                        FAST_HOLEY_SMI_ELEMENTS,
+    LoadTransitionedArrayMapConditional(FAST_SMI_ONLY_ELEMENTS,
+                                        FAST_ELEMENTS,
                                         map_out,
                                         scratch,
                                         &done);