Simplify adding of computations to the flow graph.

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 96 matching lines @@
   Instruction* entry() const { return entry_; }
   Instruction* exit() const { return exit_; }
 
   bool is_empty() const { return entry_ == NULL; }
   bool is_open() const { return is_empty() || exit_ != NULL; }
 
   void Bailout(const char* reason);
 
   // Append a graph fragment to this graph.  Assumes this graph is open.
   void Append(const EffectGraphVisitor& other_fragment);
-  // Append a single instruction.  Assumes this graph is open.
+  // Append a computation with one use.  Assumes this graph is open.
+  UseVal* Bind(Computation* computation);
+  // Append a computation with no uses.  Assumes this graph is open.
+  void Do(Computation* computation);
+  // Append a single (non-Bind, non-Do) instruction.  Assumes this graph is
+  // open.
   void AddInstruction(Instruction* instruction);
 
   // Append a 'diamond' branch and join to this graph, depending on which
   // parts are reachable.  Assumes this graph is open.
   void Join(const TestGraphVisitor& test_fragment,
             const EffectGraphVisitor& true_fragment,
             const EffectGraphVisitor& false_fragment);
 
   // Append a 'while loop' test and back edge to this graph, depending on
   // which parts are reachable.  Afterward, the graph exit is the false
   // successor of the loop condition.
   void TieLoop(const TestGraphVisitor& test_fragment,
                const EffectGraphVisitor& body_fragment);
 
  protected:
   Computation* BuildStoreLocal(const LocalVariable& local, Value* value);
   Computation* BuildLoadLocal(const LocalVariable& local);
 
   // Helpers for translating parts of the AST.
   void TranslateArgumentList(const ArgumentListNode& node,
                              ZoneGrowableArray<Value*>* values);
 
   // Creates an instantiated type argument vector used in preparation of an
   // allocation call.
   // May be called only if allocating an object of a parameterized class.
-  BindInstr* BuildInstantiatedTypeArguments(
+  Value* BuildInstantiatedTypeArguments(
       intptr_t token_pos,
       const AbstractTypeArguments& type_arguments);
 
   // 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.
   // May be called only if allocating an object of a parameterized class.
   void BuildConstructorTypeArguments(ConstructorCallNode* node,
                                      ZoneGrowableArray<Value*>* args);
 
@@ skipping 35 matching lines @@
   void CloseFragment() { exit_ = NULL; }
   intptr_t AllocateTempIndex() { return temp_index_++; }
   void DeallocateTempIndex(intptr_t n) {
     ASSERT(temp_index_ >= n);
     temp_index_ -= n;
   }
 
   virtual void CompiletimeStringInterpolation(const Function& interpol_func,
                                               const Array& literals);
 
-  BindInstr* BuildObjectAllocation(ConstructorCallNode* node);
+  Value* BuildObjectAllocation(ConstructorCallNode* node);
   void BuildConstructorCall(ConstructorCallNode* node, Value* alloc_value);
 
   void BuildStoreContext(const LocalVariable& variable);
   void BuildLoadContext(const LocalVariable& variable);
 
   void BuildThrowNode(ThrowNode* node);
 
   ClosureCallComp* BuildClosureCall(ClosureCallNode* node);
 
   Value* BuildNullValue();
 
  private:
   // Specify a computation as the final result.  Adds a Do instruction to
   // the graph, but normally overridden in subclasses.
   virtual void ReturnComputation(Computation* computation) {
-    AddInstruction(new DoInstr(computation));
+    Do(computation);
   }
 
   // Shared global state.
   FlowGraphBuilder* owner_;
 
   // Input parameters.
   intptr_t temp_index_;
 
   // Output parameters.
   Instruction* entry_;
@@ skipping 34 matching lines @@
   // Helper to set the output state to return a Value.
   virtual void ReturnValue(Value* value) {
     ASSERT(value->IsUse());
     value_ = value;
   }
 
   // Specify a computation as the final result.  Adds a Bind instruction to
   // the graph and returns its temporary value (i.e., set the output
   // parameters).
   virtual void ReturnComputation(Computation* computation) {
-    BindInstr* defn = new BindInstr(computation);
-    AddInstruction(defn);
-    ReturnValue(new UseVal(defn));
+    ReturnValue(Bind(computation));
   }
 
   virtual void CompiletimeStringInterpolation(const Function& interpol_func,
                                               const Array& literals);
 
   virtual void BuildTypeTest(ComparisonNode* node);
   virtual void BuildTypeCast(ComparisonNode* node);
 };
 
 
@@ skipping 44 matching lines @@
   // Output parameters.
   TargetEntryInstr** true_successor_address_;
   TargetEntryInstr** false_successor_address_;
 
   intptr_t condition_token_pos_;
 };
 
 }  // namespace dart
 
 #endif  // VM_FLOW_GRAPH_BUILDER_H_