[turbofan] Cache Call operator for AllocateHeapNumberStub in change lowering.

R=svenpanne@chromium.org

Review URL: https://codereview.chromium.org/1015953002

Cr-Commit-Position: refs/heads/master@{#27256}

src/compiler/change-lowering.cc

@@ -64,14 +64,17 @@ Node* ChangeLowering::AllocateHeapNumberWithValue(Node* value, Node* control) {
   // The AllocateHeapNumberStub does not use the context, so we can safely pass
   // in Smi zero here.
   Callable callable = CodeFactory::AllocateHeapNumber(isolate());
-  CallDescriptor* descriptor = Linkage::GetStubCallDescriptor(
-      isolate(), jsgraph()->zone(), callable.descriptor(), 0,
-      CallDescriptor::kNoFlags);
   Node* target = jsgraph()->HeapConstant(callable.code());
   Node* context = jsgraph()->NoContextConstant();
   Node* effect = graph()->NewNode(common()->ValueEffect(1), value);
-  Node* heap_number = graph()->NewNode(common()->Call(descriptor), target,
-                                       context, effect, control);
+  if (!allocate_heap_number_operator_.is_set()) {
+    CallDescriptor* descriptor = Linkage::GetStubCallDescriptor(
+        isolate(), jsgraph()->zone(), callable.descriptor(), 0,
+        CallDescriptor::kNoFlags, Operator::kNoThrow);
+    allocate_heap_number_operator_.set(common()->Call(descriptor));
+  }
+  Node* heap_number = graph()->NewNode(allocate_heap_number_operator_.get(),
+                                       target, context, effect, control);
   Node* store = graph()->NewNode(
       machine()->Store(StoreRepresentation(kMachFloat64, kNoWriteBarrier)),
       heap_number, HeapNumberValueIndexConstant(), value, heap_number, control);

src/compiler/change-lowering.h

@@ -16,6 +16,7 @@ class CommonOperatorBuilder;
 class JSGraph;
 class Linkage;
 class MachineOperatorBuilder;
+class Operator;
 
 class ChangeLowering FINAL : public Reducer {
  public:
@@ -54,7 +55,8 @@ class ChangeLowering FINAL : public Reducer {
   CommonOperatorBuilder* common() const;
   MachineOperatorBuilder* machine() const;
 
-  JSGraph* jsgraph_;
+  JSGraph* const jsgraph_;
+  SetOncePointer<const Operator> allocate_heap_number_operator_;
 };
 
 }  // namespace compiler