Restructure flow-graph translation of increment operations.

runtime/vm/flow_graph_builder.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_BUILDER_H_
 #define VM_FLOW_GRAPH_BUILDER_H_
 
 #include "vm/allocation.h"
 #include "vm/ast.h"
 #include "vm/growable_array.h"
@@ skipping 101 matching lines @@
   void TieLoop(const TestGraphVisitor& test_fragment,
                const EffectGraphVisitor& body_fragment);
 
  protected:
   // Helpers for translating parts of the AST.
   void TranslateArgumentList(const ArgumentListNode& node,
                              intptr_t next_temp_index,
                              ZoneGrowableArray<Value*>* values);
 
   // Build the load part of a instance field increment.  Translates the
-  // receiver and loads the value.  The receiver will be named with
-  // start_index, the temporary index of the value is returned (always
-  // start_index+1).
-  int BuildIncrOpFieldLoad(IncrOpInstanceFieldNode* node, intptr_t start_index);
+  // receiver and loads the value.  The receiver will be returned in the
+  // output parameter 'receiver'.
+  Definition* BuildIncrOpFieldLoad(IncrOpInstanceFieldNode* node,
+                                   Value** receiver);
 
   // Build the load part of an indexed increment.  Translates the receiver
-  // and index and loads the value.  The receiver will be named with
-  // start_index, the index with start_index+1, and the temporary index of
-  // the value is returned (always start_index+2).
-  int BuildIncrOpIndexedLoad(IncrOpIndexedNode* node, intptr_t start_index);
+  // and index and loads the value.  The receiver will be returned in the
+  // output parameter 'receiver' and the index will be returned in the
+  // output parameter 'index'..
+  Definition* BuildIncrOpIndexedLoad(IncrOpIndexedNode* node,
+                                     Value** receiver,
+                                     Value** index);
 
   // Build the increment part of an increment operation (add or subtract 1).
-  // The original value is expected to be named with start_index-1, and the
-  // result will be named with start_index.
-  void BuildIncrOpIncrement(Token::Kind kind,
-                            intptr_t node_id,
-                            intptr_t token_index,
-                            intptr_t start_index);
+  // Consumes the original value and produces the value +/- 1.
+  Definition* BuildIncrOpIncrement(Token::Kind kind,
+                                   intptr_t node_id,
+                                   intptr_t token_index,
+                                   Value* original);
 
   // Creates an instantiated type argument vector used in preparation of a
   // factory call.
   // May be called only if allocating an object of a parameterized class.
   Value* BuildFactoryTypeArguments(ConstructorCallNode* node,
                                    intptr_t start_index);
 
   // Creates a possibly uninstantiated type argument vector and the type
   // argument vector of the instantiator (two values in 'args') used in
   // preparation of a constructor call.
@@ skipping 24 matching lines @@
 
   virtual void BuildInstanceOf(ComparisonNode* node);
 
   bool MustSaveRestoreContext(SequenceNode* node) const;
 
   // Moves parent context into the context register.
   void UnchainContext();
 
   void CloseFragment() { exit_ = NULL; }
   intptr_t AllocateTempIndex() { return temp_index_++; }
+  void DeallocateTempIndex() { --temp_index_; }
 
   virtual void CompiletimeStringInterpolation(const Function& interpol_func,
                                               const Array& literals);
 
   TempVal* BuildObjectAllocation(ConstructorCallNode* node,
                                  int start_index);
   void BuildConstructorCall(ConstructorCallNode* node,
                             int start_index,
                             Value* alloc_value);
 
@@ skipping 146 matching lines @@
   TargetEntryInstr** true_successor_address_;
   TargetEntryInstr** false_successor_address_;
 
   intptr_t condition_node_id_;
   intptr_t condition_token_index_;
 };
 
 }  // namespace dart
 
 #endif  // VM_FLOW_GRAPH_BUILDER_H_