[turbofan] Adds an Allocate macro to the CodeStubAssembler.

src/code-stubs.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/code-stubs.h"
 
 #include <sstream>
 
 #include "src/bootstrapper.h"
 #include "src/compiler/code-stub-assembler.h"
@@ skipping 454 matching lines @@
 void StringLengthStub::GenerateAssembly(
     compiler::CodeStubAssembler* assembler) const {
   compiler::Node* value = assembler->Parameter(0);
   compiler::Node* string =
       assembler->LoadObjectField(value, JSValue::kValueOffset);
   compiler::Node* result =
       assembler->LoadObjectField(string, String::kLengthOffset);
   assembler->Return(result);
 }
 
+void AllocateHeapNumberStub::GenerateAssembly(
+    compiler::CodeStubAssembler* assembler) const {
+  compiler::Node* result = assembler->Allocate(
+      HeapNumber::kSize, compiler::AllocationFlags::kTagObject);
+
+  assembler->StoreNoWriteBarrier(
+      MachineRepresentation::kTagged,
+      assembler->IntPtrAdd(

[Benedikt Meurer, 2016/02/25 13:00:40]

Please don't nest these computations, add separate named temporaries as in the
StringLengthStub please.

[epertoso, 2016/02/25 13:26:53]

Done.

+          result,
+          assembler->IntPtrConstant(HeapObject::kMapOffset - kHeapObjectTag)),
+      assembler->HeapConstant(isolate()->factory()->heap_number_map()));
+  assembler->Return(result);
+}
+
+void AllocateMutableHeapNumberStub::GenerateAssembly(
+    compiler::CodeStubAssembler* assembler) const {
+  compiler::Node* result = assembler->Allocate(
+      HeapNumber::kSize, compiler::AllocationFlags::kTagObject);
+  assembler->StoreNoWriteBarrier(

[Benedikt Meurer, 2016/02/25 13:00:40]

Same here.

[epertoso, 2016/02/25 13:26:53]

Done.

+      MachineRepresentation::kTagged,
+      assembler->IntPtrAdd(
+          result,
+          assembler->IntPtrConstant(HeapObject::kMapOffset - kHeapObjectTag)),
+      assembler->HeapConstant(isolate()->factory()->mutable_heap_number_map()));
+  assembler->Return(result);
+}
 
 template<class StateType>
 void HydrogenCodeStub::TraceTransition(StateType from, StateType to) {
   // Note: Although a no-op transition is semantically OK, it is hinting at a
   // bug somewhere in our state transition machinery.
   DCHECK(from != to);
   if (!FLAG_trace_ic) return;
   OFStream os(stdout);
   os << "[";
   PrintBaseName(os);
@@ skipping 422 matching lines @@
   if (type->Is(Type::UntaggedPointer())) {
     return Representation::External();
   }
 
   DCHECK(!type->Is(Type::Untagged()));
   return Representation::Tagged();
 }
 
 }  // namespace internal
 }  // namespace v8