Simplify allocation stub for closures.

runtime/vm/stub_code_x64.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/assembler.h"
 #include "vm/compiler.h"
 #include "vm/dart_entry.h"
@@ skipping 987 matching lines @@
 //   RSP + 16 : type arguments object (only if class is parameterized).
 //   RSP + 8 : type arguments of instantiator (only if class is parameterized).
 //   RSP : points to return address.
 void StubCode::GenerateAllocationStubForClass(Assembler* assembler,
                                               const Class& cls) {
   const intptr_t kObjectTypeArgumentsOffset = 2 * kWordSize;
   const intptr_t kInstantiatorTypeArgumentsOffset = 1 * kWordSize;
   const Immediate& raw_null =
       Immediate(reinterpret_cast<intptr_t>(Object::null()));
   // The generated code is different if the class is parameterized.
-  const bool is_cls_parameterized =
-      cls.type_arguments_field_offset() != Class::kNoTypeArguments;
+  const bool is_cls_parameterized = cls.HasTypeArguments();
+  ASSERT(!cls.HasTypeArguments() ||
+         cls.type_arguments_field_offset() != Class::kNoTypeArguments);
   // kInlineInstanceSize is a constant used as a threshold for determining
   // when the object initialization should be done as a loop or as
   // straight line code.
   const int kInlineInstanceSize = 12;  // In words.
   const intptr_t instance_size = cls.instance_size();
   ASSERT(instance_size > 0);
   const intptr_t type_args_size = InstantiatedTypeArguments::InstanceSize();
   if (FLAG_inline_alloc &&
       Heap::IsAllocatableInNewSpace(instance_size + type_args_size)) {
     Label slow_case;
@@ skipping 151 matching lines @@
 // Called for inline allocation of closures.
 // Input parameters:
 //   RSP + 16 : receiver (null if not an implicit instance closure).
 //   RSP + 8 : type arguments object (null if class is not parameterized).
 //   RSP : points to return address.
 void StubCode::GenerateAllocationStubForClosure(Assembler* assembler,
                                                 const Function& func) {
   const Immediate& raw_null =
       Immediate(reinterpret_cast<intptr_t>(Object::null()));
   ASSERT(func.IsClosureFunction());
-  const bool is_implicit_static_closure =
-      func.IsImplicitStaticClosureFunction();
+  ASSERT(!func.IsImplicitStaticClosureFunction());
   const bool is_implicit_instance_closure =
       func.IsImplicitInstanceClosureFunction();
   const Class& cls = Class::ZoneHandle(func.signature_class());
   const bool has_type_arguments = cls.HasTypeArguments();
   const intptr_t kTypeArgumentsOffset = 1 * kWordSize;
   const intptr_t kReceiverOffset = 2 * kWordSize;
   const intptr_t closure_size = Closure::InstanceSize();
   const intptr_t context_size = Context::InstanceSize(1);  // Captured receiver.
   if (FLAG_inline_alloc &&
       Heap::IsAllocatableInNewSpace(closure_size + context_size)) {
@@ skipping 32 matching lines @@
     __ movq(Address(RAX, Instance::tags_offset()), Immediate(tags));
 
     // Initialize the function field in the object.
     // RAX: new closure object.
     // RBX: new context object (only if is_implicit_closure).
     // R13: next object start.
     __ LoadObject(R10, func);  // Load function of closure to be allocated.
     __ movq(Address(RAX, Closure::function_offset()), R10);
 
     // Setup the context for this closure.
-    if (is_implicit_static_closure) {
-      ObjectStore* object_store = Isolate::Current()->object_store();
-      ASSERT(object_store != NULL);
-      const Context& empty_context =
-          Context::ZoneHandle(object_store->empty_context());
-      __ LoadObject(R10, empty_context);
-      __ movq(Address(RAX, Closure::context_offset()), R10);
-    } else if (is_implicit_instance_closure) {
+    if (is_implicit_instance_closure) {
       // Initialize the new context capturing the receiver.
 
       const Class& context_class = Class::ZoneHandle(Object::context_class());
       // Set the tags.
       uword tags = 0;
       tags = RawObject::SizeTag::update(context_size, tags);
       tags = RawObject::ClassIdTag::update(context_class.id(), tags);
       __ movq(Address(RBX, Context::tags_offset()), Immediate(tags));
 
       // Set number of variables field to 1 (for captured receiver).
@@ skipping 31 matching lines @@
   if (has_type_arguments) {
     __ movq(RCX, Address(RSP, kTypeArgumentsOffset));
   }
   if (is_implicit_instance_closure) {
     __ movq(RAX, Address(RSP, kReceiverOffset));
   }
   // Create the stub frame.
   __ EnterStubFrame();
   __ pushq(raw_null);  // Setup space on stack for the return value.
   __ PushObject(func);
-  if (is_implicit_static_closure) {
-    __ CallRuntime(kAllocateImplicitStaticClosureRuntimeEntry);
+  if (is_implicit_instance_closure) {
+    __ pushq(RAX);  // Receiver.
+  }
+  if (has_type_arguments) {
+    __ pushq(RCX);  // Push type arguments of closure to be allocated.
   } else {
-    if (is_implicit_instance_closure) {
-      __ pushq(RAX);  // Receiver.
-    }
-    if (has_type_arguments) {
-      __ pushq(RCX);  // Push type arguments of closure to be allocated.
-    } else {
-      __ pushq(raw_null);  // Push null type arguments.
-    }
-    if (is_implicit_instance_closure) {
-      __ CallRuntime(kAllocateImplicitInstanceClosureRuntimeEntry);
-      __ popq(RAX);  // Pop type arguments.
-      __ popq(RAX);  // Pop receiver.
-    } else {
-      ASSERT(func.IsNonImplicitClosureFunction());
-      __ CallRuntime(kAllocateClosureRuntimeEntry);
-      __ popq(RAX);  // Pop type arguments.
-    }
+    __ pushq(raw_null);  // Push null type arguments.
+  }
+  if (is_implicit_instance_closure) {
+    __ CallRuntime(kAllocateImplicitInstanceClosureRuntimeEntry);
+    __ popq(RAX);  // Pop type arguments.
+    __ popq(RAX);  // Pop receiver.
+  } else {
+    ASSERT(func.IsNonImplicitClosureFunction());
+    __ CallRuntime(kAllocateClosureRuntimeEntry);
+    __ popq(RAX);  // Pop type arguments.
   }
   __ popq(RAX);  // Pop the function object.
   __ popq(RAX);  // Pop the result.
   // RAX: New closure object.
   // Restore the calling frame.
   __ LeaveFrame();
   __ ret();
 }
 
 
@@ skipping 845 matching lines @@
   __ movq(right, Address(RSP, 3 * kWordSize));
   GenerateIdenticalWithNumberCheckStub(assembler, left, right);
   __ popq(right);
   __ popq(left);
   __ ret();
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64