--debug-code: sanity-checking instrumentation for Lithium object accesses

src/hydrogen-instructions.cc

Index: src/hydrogen-instructions.cc
diff --git a/src/hydrogen-instructions.cc b/src/hydrogen-instructions.cc
index 44a6dde00e470c45acb2b214648a0998c662a28e..fb955913af603919b0fddbf34af464e8e9d78534 100644
--- a/src/hydrogen-instructions.cc
+++ b/src/hydrogen-instructions.cc
@@ -4015,6 +4015,7 @@ void HAllocate::CreateFreeSpaceFiller(int32_t free_space_size) {
   HObjectAccess access =
       HObjectAccess::ForMapAndOffset(isolate()->factory()->free_space_map(),
                                      FreeSpace::kSizeOffset,
+                                     HObjectAccess::FOR_FIELD,
                                      Representation::Smi());
   HStoreNamedField* store_size = HStoreNamedField::New(zone, context(),
       free_space_instr, access, filler_size);
@@ -4609,48 +4610,50 @@ HObjectAccess HObjectAccess::ForFixedArrayHeader(int offset) {
   ASSERT(offset >= 0);
   ASSERT(offset < FixedArray::kHeaderSize);
   if (offset == FixedArray::kLengthOffset) return ForFixedArrayLength();
-  return HObjectAccess(kInobject, offset);
+  return HObjectAccess(kInobject, offset, FOR_FIXED_ARRAY_HEADER);
 }
 
 
 HObjectAccess HObjectAccess::ForMapAndOffset(Handle<Map> map, int offset,
-    Representation representation) {
+    Purpose purpose, Representation representation) {
   ASSERT(offset >= 0);
   Portion portion = kInobject;
 
-  if (offset == JSObject::kElementsOffset) {
+  if (offset == JSObject::kElementsOffset &&
+      !map.is_null() && map->IsJSObjectMap()) {
     portion = kElementsPointer;
+    purpose = FOR_ELEMENTS_POINTER;
   } else if (offset == JSObject::kMapOffset) {
     portion = kMaps;
+    purpose = FOR_MAP;
   }
   bool existing_inobject_property = true;
   if (!map.is_null()) {
     existing_inobject_property = (offset <
         map->instance_size() - map->unused_property_fields() * kPointerSize);
   }
-  return HObjectAccess(portion, offset, representation, Handle<String>::null(),
-                       false, existing_inobject_property);
+  return HObjectAccess(portion, offset, purpose, representation,
+                       Handle<String>::null(), false,
+                       existing_inobject_property);
 }
 
 
 HObjectAccess HObjectAccess::ForAllocationSiteOffset(int offset) {
   switch (offset) {
-    case AllocationSite::kTransitionInfoOffset:
-      return HObjectAccess(kInobject, offset, Representation::Tagged());
+    case AllocationSite::kDependentCodeOffset:
     case AllocationSite::kNestedSiteOffset:
-      return HObjectAccess(kInobject, offset, Representation::Tagged());
+    case AllocationSite::kTransitionInfoOffset:
+    case AllocationSite::kWeakNextOffset:
+      return HObjectAccess(kInobject, offset, FOR_ALLOCATION_SITE_OFFSET,
+                           Representation::Tagged());
     case AllocationSite::kPretenureDataOffset:
-      return HObjectAccess(kInobject, offset, Representation::Smi());
     case AllocationSite::kPretenureCreateCountOffset:
-      return HObjectAccess(kInobject, offset, Representation::Smi());
-    case AllocationSite::kDependentCodeOffset:
-      return HObjectAccess(kInobject, offset, Representation::Tagged());
-    case AllocationSite::kWeakNextOffset:
-      return HObjectAccess(kInobject, offset, Representation::Tagged());
+      return HObjectAccess(kInobject, offset, FOR_ALLOCATION_SITE_OFFSET,
+                           Representation::Smi());
     default:
       UNREACHABLE();
   }
-  return HObjectAccess(kInobject, offset);
+  return HObjectAccess(kInobject, offset, FOR_ALLOCATION_SITE_OFFSET);
 }
 
 
@@ -4659,30 +4662,35 @@ HObjectAccess HObjectAccess::ForContextSlot(int index) {
   Portion portion = kInobject;
   int offset = Context::kHeaderSize + index * kPointerSize;
   ASSERT_EQ(offset, Context::SlotOffset(index) + kHeapObjectTag);
-  return HObjectAccess(portion, offset, Representation::Tagged());
+  return HObjectAccess(portion, offset, FOR_CONTEXT_SLOT,
+                       Representation::Tagged());
 }
 
 
 HObjectAccess HObjectAccess::ForJSArrayOffset(int offset) {
   ASSERT(offset >= 0);
   Portion portion = kInobject;
+  Purpose purpose = FOR_JSARRAY_OFFSET;
 
   if (offset == JSObject::kElementsOffset) {
     portion = kElementsPointer;
+    purpose = FOR_ELEMENTS_POINTER;
   } else if (offset == JSArray::kLengthOffset) {
     portion = kArrayLengths;
+    purpose = FOR_ARRAY_LENGTH;
   } else if (offset == JSObject::kMapOffset) {
     portion = kMaps;
+    purpose = FOR_MAP;
   }
-  return HObjectAccess(portion, offset);
+  return HObjectAccess(portion, offset, purpose);
 }
 
 
 HObjectAccess HObjectAccess::ForBackingStoreOffset(int offset,
     Representation representation) {
   ASSERT(offset >= 0);
-  return HObjectAccess(kBackingStore, offset, representation,
-                       Handle<String>::null(), false, false);
+  return HObjectAccess(kBackingStore, offset, FOR_BACKING_STORE_OFFSET,
+                       representation, Handle<String>::null(), false, false);
 }
 
 
@@ -4708,19 +4716,20 @@ HObjectAccess HObjectAccess::ForField(Handle<Map> map,
     // Negative property indices are in-object properties, indexed
     // from the end of the fixed part of the object.
     int offset = (index * kPointerSize) + map->instance_size();
-    return HObjectAccess(kInobject, offset, representation, name, false, true);
+    return HObjectAccess(kInobject, offset, FOR_FIELD, representation, name,
+                         false, true);
   } else {
     // Non-negative property indices are in the properties array.
     int offset = (index * kPointerSize) + FixedArray::kHeaderSize;
-    return HObjectAccess(kBackingStore, offset, representation, name,
-                         false, false);
+    return HObjectAccess(kBackingStore, offset, FOR_BACKING_STORE_OFFSET,
+                         representation, name, false, false);
   }
 }
 
 
 HObjectAccess HObjectAccess::ForCellPayload(Isolate* isolate) {
   return HObjectAccess(
-      kInobject, Cell::kValueOffset, Representation::Tagged(),
+      kInobject, Cell::kValueOffset, FOR_CELL_PAYLOAD, Representation::Tagged(),
       Handle<String>(isolate->heap()->cell_value_string()));
 }