Implement a simple register allocator that tries to keep instruction results in registers.

runtime/vm/flow_graph_compiler_x64.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_FLOW_GRAPH_COMPILER_X64_H_
 #define VM_FLOW_GRAPH_COMPILER_X64_H_
 
 #ifndef VM_FLOW_GRAPH_COMPILER_H_
 #error Include flow_graph_compiler.h instead of flow_graph_compiler_x64.h.
 #endif
 
-#include "vm/assembler.h"
-#include "vm/assembler_macros.h"
-#include "vm/code_descriptors.h"
-#include "vm/code_generator.h"
-#include "vm/intermediate_language.h"
-
 namespace dart {
 
 class Code;
 class DeoptimizationStub;
 class ExceptionHandlerList;
 template <typename T> class GrowableArray;
 class ParsedFunction;
 
 class FlowGraphCompiler : public ValueObject {
  private:
   struct BlockInfo : public ZoneAllocated {
    public:
     BlockInfo() : label() { }
     Label label;
   };
 
  public:
   FlowGraphCompiler(Assembler* assembler,
                     const ParsedFunction& parsed_function,
                     const GrowableArray<BlockEntryInstr*>& block_order,
                     bool is_optimizing);
 
-  virtual ~FlowGraphCompiler();
+  ~FlowGraphCompiler();
 
   // Accessors.
   Assembler* assembler() const { return assembler_; }
   const ParsedFunction& parsed_function() const { return parsed_function_; }
   const GrowableArray<BlockEntryInstr*>& block_order() const {
     return block_order_;
   }
   DescriptorList* pc_descriptors_list() const {
     return pc_descriptors_list_;
   }
@@ skipping 17 matching lines @@
 
   void LoadDoubleOrSmiToXmm(XmmRegister result,
                             Register reg,
                             Register temp,
                             Label* not_double_or_smi);
 
   // Returns 'true' if code generation for this function is complete, i.e.,
   // no fall-through to regular code is needed.
   bool TryIntrinsify();
 
-  virtual void GenerateCallRuntime(intptr_t cid,
-                                   intptr_t token_index,
-                                   intptr_t try_index,
-                                   const RuntimeEntry& entry);
+  void GenerateCallRuntime(intptr_t cid,
+                           intptr_t token_index,
+                           intptr_t try_index,
+                           const RuntimeEntry& entry);
 
   // Infrastructure copied from class CodeGenerator.
   void GenerateCall(intptr_t token_index,
                     intptr_t try_index,
                     const ExternalLabel* label,
                     PcDescriptors::Kind kind);
 
   void GenerateAssertAssignable(intptr_t cid,
                                 intptr_t token_index,
                                 intptr_t try_index,
@@ skipping 14 matching lines @@
                             const Array& argument_names,
                             intptr_t checked_argument_count);
 
   void GenerateStaticCall(intptr_t cid,
                           intptr_t token_index,
                           intptr_t try_index,
                           const Function& function,
                           intptr_t argument_count,
                           const Array& argument_names);
 
-  virtual void GenerateInlinedMathSqrt(Label* done);
+  void GenerateInlinedMathSqrt(Label* done);
 
   void GenerateNumberTypeCheck(Register kClassIdReg,
                                const AbstractType& type,
                                Label* is_instance_lbl,
                                Label* is_not_instance_lbl);
   void GenerateStringTypeCheck(Register kClassIdReg,
                                Label* is_instance_lbl,
                                Label* is_not_instance_lbl);
   void GenerateListTypeCheck(Register kClassIdReg,
                              Label* is_instance_lbl);
@@ skipping 39 matching lines @@
   void FinalizeExceptionHandlers(const Code& code);
   void FinalizePcDescriptors(const Code& code);
   void FinalizeStackmaps(const Code& code);
   void FinalizeVarDescriptors(const Code& code);
   void FinalizeComments(const Code& code);
 
   const Bool& bool_true() const { return bool_true_; }
   const Bool& bool_false() const { return bool_false_; }
   const Class& double_class() const { return double_class_; }
 
+  FrameRegisterAllocator* frame_register_allocator() {
+    return &frame_register_allocator_;
+  }
+
   static const int kLocalsOffsetFromFP = (-1 * kWordSize);
 
  private:
   friend class DeoptimizationStub;
 
   void GenerateDeferredCode();
 
-  virtual void EmitInstructionPrologue(Instruction* instr);
+  void EmitInstructionPrologue(Instruction* instr);
 
   // Emit code to load a Value into register 'dst'.
   void LoadValue(Register dst, Value* value);
 
   // Returns pc-offset (in bytes) of the pc after the call, can be used to emit
   // pc-descriptor information.
-  virtual intptr_t EmitStaticCall(const Function& function,
-                                  const Array& arguments_descriptor,
-                                  intptr_t argument_count);
+  intptr_t EmitStaticCall(const Function& function,
+                          const Array& arguments_descriptor,
+                          intptr_t argument_count);
 
   // Type checking helper methods.
-  virtual void CheckClassIds(Register class_id_reg,
-                             const GrowableArray<intptr_t>& class_ids,
-                             Label* is_instance_lbl,
-                             Label* is_not_instance_lbl);
+  void CheckClassIds(Register class_id_reg,
+                     const GrowableArray<intptr_t>& class_ids,
+                     Label* is_instance_lbl,
+                     Label* is_not_instance_lbl);
 
   RawSubtypeTestCache* GenerateInlineInstanceof(intptr_t cid,
                                                 intptr_t token_index,
                                                 const AbstractType& type,
                                                 Label* is_instance_lbl,
                                                 Label* is_not_instance_lbl);
 
   RawSubtypeTestCache* GenerateInstantiatedTypeWithArgumentsTest(
       intptr_t cid,
       intptr_t token_index,
@@ skipping 31 matching lines @@
                                                    Register instance_reg,
                                                    Register type_arguments_reg,
                                                    Register temp_reg,
                                                    Label* is_instance_lbl,
                                                    Label* is_not_instance_lbl);
 
   void GenerateBoolToJump(Register bool_reg, Label* is_true, Label* is_false);
 
   void CopyParameters();
 
-  virtual void GenerateInlinedGetter(intptr_t offset);
-  virtual void GenerateInlinedSetter(intptr_t offset);
+  void GenerateInlinedGetter(intptr_t offset);
+  void GenerateInlinedSetter(intptr_t offset);
 
   // Map a block number in a forward iteration into the block number in the
   // corresponding reverse iteration.  Used to obtain an index into
   // block_order for reverse iterations.
   intptr_t reverse_index(intptr_t index) const {
     return block_order_.length() - index - 1;
   }
 
   class Assembler* assembler_;
   const ParsedFunction& parsed_function_;
   const GrowableArray<BlockEntryInstr*>& block_order_;
 
   // Compiler specific per-block state.  Indexed by postorder block number
   // for convenience.  This is not the block's index in the block order,
   // which is reverse postorder.
   BlockEntryInstr* current_block_;
   ExceptionHandlerList* exception_handlers_list_;
   DescriptorList* pc_descriptors_list_;
   StackmapBuilder* stackmap_builder_;
   GrowableArray<BlockInfo*> block_info_;
   GrowableArray<DeoptimizationStub*> deopt_stubs_;
   const bool is_optimizing_;
 
   const Bool& bool_true_;
   const Bool& bool_false_;
   const Class& double_class_;
 
+  FrameRegisterAllocator frame_register_allocator_;
+
   DISALLOW_COPY_AND_ASSIGN(FlowGraphCompiler);
 };
 
 
 class DeoptimizationStub : public ZoneAllocated {
  public:
   DeoptimizationStub(intptr_t deopt_id,
                      intptr_t deopt_token_index,
                      intptr_t try_index,
                      DeoptReasonId reason)
@@ skipping 17 matching lines @@
   const DeoptReasonId reason_;
   GrowableArray<Register> registers_;
   Label entry_label_;
 
   DISALLOW_COPY_AND_ASSIGN(DeoptimizationStub);
 };
 
 }  // namespace dart
 
 #endif  // VM_FLOW_GRAPH_COMPILER_X64_H_