Move GetRootListIndex into Heap.

R=hpayer@chromium.org
BUG=

Review URL: https://codereview.chromium.org/1095513003

Cr-Commit-Position: refs/heads/master@{#27891}

src/compiler/code-generator.cc

@@ -202,13 +202,7 @@ bool CodeGenerator::IsMaterializableFromFrame(Handle<HeapObject> object,
 bool CodeGenerator::IsMaterializableFromRoot(
     Handle<HeapObject> object, Heap::RootListIndex* index_return) {
   if (linkage()->GetIncomingDescriptor()->IsJSFunctionCall()) {
-#define IMMORTAL_IMMOVABLE_ROOT(Name)                                 \
-  if (*object == isolate()->heap()->root(Heap::k##Name##RootIndex)) { \
-    *index_return = Heap::k##Name##RootIndex;                         \
-    return true;                                                      \
-  }
-    IMMORTAL_IMMOVABLE_ROOT_LIST(IMMORTAL_IMMOVABLE_ROOT)
-#undef IMMORTAL_IMMOVABLE_ROOT
+    return isolate()->heap()->GetRootListIndex(object, index_return);
   }
   return false;
 }

src/heap/heap.cc

@@ -4808,6 +4808,20 @@ bool Heap::RootIsImmortalImmovable(int root_index) {
 }
 
 
+bool Heap::GetRootListIndex(Handle<HeapObject> object,
+                            Heap::RootListIndex* index_return) {
+  Object* ptr = *object;
+#define IMMORTAL_IMMOVABLE_ROOT(Name)            \
+  if (ptr == roots_[Heap::k##Name##RootIndex]) { \
+    *index_return = k##Name##RootIndex;          \
+    return true;                                 \
+  }
+  IMMORTAL_IMMOVABLE_ROOT_LIST(IMMORTAL_IMMOVABLE_ROOT)
+#undef IMMORTAL_IMMOVABLE_ROOT
+  return false;
+}
+
+
 #ifdef VERIFY_HEAP
 void Heap::Verify() {
   CHECK(HasBeenSetUp());

src/heap/heap.h

@@ -1166,6 +1166,10 @@ class Heap {
     kSmiRootsStart = kStringTableRootIndex + 1
   };
 
+  // Get the root list index for {object} if such a root list index exists.
+  bool GetRootListIndex(Handle<HeapObject> object,
+                        Heap::RootListIndex* index_return);
+
   Object* root(RootListIndex index) { return roots_[index]; }
 
   STATIC_ASSERT(kUndefinedValueRootIndex ==