First step towards implementing stack map descriptions for the optimizing compiler.

vm/object.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_OBJECT_H_
 #define VM_OBJECT_H_
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "platform/utils.h"
+#include "vm/bitmap.h"
 #include "vm/dart.h"
 #include "vm/globals.h"
 #include "vm/handles.h"
 #include "vm/heap.h"
 #include "vm/isolate.h"
 #include "vm/os.h"
 #include "vm/raw_object.h"
 #include "vm/scanner.h"
 
 namespace dart {
@@ skipping 124 matching lines @@
     kFunctionClass,
     kFieldClass,
     kLiteralTokenClass,
     kTokenStreamClass,
     kScriptClass,
     kLibraryClass,
     kLibraryPrefixClass,
     kCodeClass,
     kInstructionsClass,
     kPcDescriptorsClass,
+    kStackmapClass,
     kLocalVarDescriptorsClass,
     kExceptionHandlersClass,
     kContextClass,
     kContextScopeClass,
     kICDataClass,
     kApiErrorClass,
     kLanguageErrorClass,
     kUnhandledExceptionClass,
     kUnwindErrorClass,
     kMaxId,
@@ skipping 116 matching lines @@
   static RawClass* function_class() { return function_class_; }
   static RawClass* field_class() { return field_class_; }
   static RawClass* literal_token_class() { return literal_token_class_; }
   static RawClass* token_stream_class() { return token_stream_class_; }
   static RawClass* script_class() { return script_class_; }
   static RawClass* library_class() { return library_class_; }
   static RawClass* library_prefix_class() { return library_prefix_class_; }
   static RawClass* code_class() { return code_class_; }
   static RawClass* instructions_class() { return instructions_class_; }
   static RawClass* pc_descriptors_class() { return pc_descriptors_class_; }
+  static RawClass* stackmap_class() { return stackmap_class_; }
   static RawClass* var_descriptors_class() { return var_descriptors_class_; }
   static RawClass* exception_handlers_class() {
     return exception_handlers_class_;
   }
   static RawClass* context_class() { return context_class_; }
   static RawClass* context_scope_class() { return context_scope_class_; }
   static RawClass* api_error_class() { return api_error_class_; }
   static RawClass* language_error_class() { return language_error_class_; }
   static RawClass* unhandled_exception_class() {
     return unhandled_exception_class_;
@@ skipping 87 matching lines @@
   static RawClass* function_class_;  // Class of the Function vm object.
   static RawClass* field_class_;  // Class of the Field vm object.
   static RawClass* literal_token_class_;  // Class of LiteralToken vm object.
   static RawClass* token_stream_class_;  // Class of the TokenStream vm object.
   static RawClass* script_class_;  // Class of the Script vm object.
   static RawClass* library_class_;  // Class of the Library vm object.
   static RawClass* library_prefix_class_;  // Class of Library prefix vm object.
   static RawClass* code_class_;  // Class of the Code vm object.
   static RawClass* instructions_class_;  // Class of the Instructions vm object.
   static RawClass* pc_descriptors_class_;  // Class of PcDescriptors vm object.
+  static RawClass* stackmap_class_;  // Class of Stackmap vm object.
   static RawClass* var_descriptors_class_;  // Class of LocalVarDescriptors.
   static RawClass* exception_handlers_class_;  // Class of ExceptionHandlers.
   static RawClass* context_class_;  // Class of the Context vm object.
   static RawClass* context_scope_class_;  // Class of ContextScope vm object.
   static RawClass* icdata_class_;  // Class of ICData.
   static RawClass* api_error_class_;  // Class of ApiError.
   static RawClass* language_error_class_;  // Class of LanguageError.
   static RawClass* unhandled_exception_class_;  // Class of UnhandledException.
   static RawClass* unwind_error_class_;  // Class of UnwindError.
 
@@ skipping 1569 matching lines @@
   }
   RawSmi** SmiAddr(intptr_t index, intptr_t entry_offset) const {
     return reinterpret_cast<RawSmi**>(EntryAddr(index, entry_offset));
   }
 
   HEAP_OBJECT_IMPLEMENTATION(PcDescriptors, Object);
   friend class Class;
 };
 
 
+class Stackmap : public Object {
+ public:
+  static const intptr_t kNoMaximum = -1;
+  static const intptr_t kNoMinimum = -1;
+
+  bool IsObject(intptr_t offset) const {
+    return InRange(offset) && GetBit(offset);
+  }
+  uword pc() const { return raw_ptr()->pc_; }
+
+  static intptr_t InstanceSize() {
+    ASSERT(sizeof(RawStackmap) == OFFSET_OF(RawStackmap, data_));
+    return 0;
+  }
+  static intptr_t InstanceSize(intptr_t size) {
+    return RoundedAllocationSize(sizeof(RawStackmap) + (size * kWordSize));
+  }
+  static RawStackmap* New(uword pc, const Code& code, BitmapBuilder* bmap);
+
+ private:
+  inline intptr_t SizeInBits() const;
+
+  bool InRange(intptr_t offset) const { return offset < SizeInBits(); }
+
+  bool GetBit(intptr_t bit_offset) const;
+  void SetBit(intptr_t bit_offset, bool value) const;
+
+  // Return the offset of the highest stack slot that has an object.
+  intptr_t Maximum() const;
+
+  // Return the offset of the lowest stack slot that has an object.
+  intptr_t Minimum() const;
+
+  void set_bitmap_size_in_bytes(intptr_t value) const;
+  void set_pc(uword value) const;
+  void set_code(const Code& code) const;
+
+  HEAP_OBJECT_IMPLEMENTATION(Stackmap, Object);
+  friend class Class;
+  friend class BitmapBuilder;
+};
+
+
 class ExceptionHandlers : public Object {
  public:
   intptr_t Length() const;
 
   intptr_t TryIndex(intptr_t index) const;
   intptr_t HandlerPC(intptr_t index) const;
 
   void SetHandlerEntry(intptr_t index,
                        intptr_t try_index,
                        intptr_t handler_pc) const {
@@ skipping 1830 matching lines @@
   }
   ASSERT(obj.IsString());  // Must be an identifier.
   return Token::kIDENT;
 }
 
 
 void Context::SetAt(intptr_t index, const Instance& value) const {
   StorePointer(InstanceAddr(index), value.raw());
 }
 
+
+intptr_t Stackmap::SizeInBits() const {
+  return (Smi::Value(raw_ptr()->bitmap_size_in_bytes_) * kBitsPerByte);
+}
+
 }  // namespace dart
 
 #endif  // VM_OBJECT_H_