Add a stub_code_space in the heap alongside code_space so that stub code generation happens here an…

vm/heap.h

 // Copyright (c) 2012, 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.
 
 #ifndef VM_HEAP_H_
 #define VM_HEAP_H_
 
 #include "platform/assert.h"
 #include "vm/allocation.h"
 #include "vm/flags.h"
@@ skipping 11 matching lines @@
 DECLARE_FLAG(bool, verbose_gc);
 DECLARE_FLAG(bool, verify_before_gc);
 DECLARE_FLAG(bool, verify_after_gc);
 DECLARE_FLAG(bool, gc_at_alloc);
 
 class Heap {
  public:
   enum Space {
     kNew,
     kOld,
-    kExecutable
+    kDartCode,
+    kStubCode,
   };
 
   enum ApiCallbacks {
     kIgnoreApiCallbacks,
     kInvokeApiCallbacks
   };
 
   // Default allocation sizes in MB for the old gen and code heaps.
   static const intptr_t kHeapSizeInMB = 512;
   static const intptr_t kCodeHeapSizeInMB = 8;
+  static const intptr_t kStubCodeHeapSizeInKB = 256;
 
   ~Heap();
 
   uword Allocate(intptr_t size, Space space) {
     switch (space) {
       case kNew:
         // Do not attempt to allocate very large objects in new space.
         if (!PageSpace::IsPageAllocatableSize(size)) {
           return AllocateOld(size);
         }
         return AllocateNew(size);
       case kOld:
         return AllocateOld(size);
-      case kExecutable:
-        return AllocateCode(size);
+      case kDartCode:
+        return AllocateCode(code_space_, size);
+      case kStubCode:
+        return AllocateCode(stub_code_space_, size);
       default:
         UNREACHABLE();
     }
     return 0;
   }
 
   uword TryAllocate(intptr_t size, Space space) {
     switch (space) {
       case kNew:
         return new_space_->TryAllocate(size);
       case kOld:
         return old_space_->TryAllocate(size);
-      case kExecutable:
+      case kDartCode:
         return code_space_->TryAllocate(size);
+      case kStubCode:
+        return stub_code_space_->TryAllocate(size);
       default:
         UNREACHABLE();
     }
     return 0;
   }
 
   // Heap contains the specified address.
   bool Contains(uword addr) const;
   bool CodeContains(uword addr) const;
+  bool StubCodeContains(uword addr) const;
 
   // Visit all pointers in the space.
   void IterateNewPointers(ObjectPointerVisitor* visitor);
   void IterateOldPointers(ObjectPointerVisitor* visitor);
   void IterateCodePointers(ObjectPointerVisitor* visitor);
+  void IterateStubCodePointers(ObjectPointerVisitor* visitor);
 
   // Find an object by visiting all pointers in the specified heap space,
   // the 'visitor' is used to determine if an object is found or not.
   // The 'visitor' function should be set up to return true if the
   // object is found, traversal through the heap space stops at that
   // point.
   // The 'visitor' function should return false if the object is not found,
   // traversal through the heap space continues.
   RawInstructions* FindObjectInCodeSpace(FindObjectVisitor* visitor);
+  RawInstructions* FindObjectInStubCodeSpace(FindObjectVisitor* visitor);
 
   void CollectGarbage(Space space);
   void CollectGarbage(Space space, ApiCallbacks api_callbacks);
   void CollectAllGarbage();
 
   // Accessors for inlined allocation in generated code.
   uword TopAddress();
   uword EndAddress();
   static intptr_t new_space_offset() { return OFFSET_OF(Heap, new_space_); }
 
   // Initialize the heap and register it with the isolate.
   static void Init(Isolate* isolate);
 
   // Verify that all pointers in the heap point to the heap.
   bool Verify() const;
 
  private:
   Heap();
 
   uword AllocateNew(intptr_t size);
   uword AllocateOld(intptr_t size);
-  uword AllocateCode(intptr_t size);
+  uword AllocateCode(PageSpace* space, intptr_t size);
 
   // The different spaces used for allocation.
   Scavenger* new_space_;
   PageSpace* old_space_;
   PageSpace* code_space_;
+  PageSpace* stub_code_space_;
 
   DISALLOW_COPY_AND_ASSIGN(Heap);
 };
 
 
 #if defined(DEBUG)
 class NoGCScope : public StackResource {
  public:
   NoGCScope();
   ~NoGCScope();
  private:
   DISALLOW_COPY_AND_ASSIGN(NoGCScope);
 };
 #else  // defined(DEBUG)
 class NoGCScope : public ValueObject {
  public:
   NoGCScope() {}
  private:
   DISALLOW_COPY_AND_ASSIGN(NoGCScope);
 };
 #endif  // defined(DEBUG)
 
 }  // namespace dart
 
 #endif  // VM_HEAP_H_