Inlining of static calls with trivial function bodies.

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"
 #include "vm/intermediate_language.h"
 
 namespace dart {
 
 class FlowGraph;
 class Instruction;
 class ParsedFunction;
 
 // Build a flow graph from a parsed function's AST.
 class FlowGraphBuilder: public ValueObject {
  public:
   explicit FlowGraphBuilder(const ParsedFunction& parsed_function);
 
+  enum InliningContext {
+    kNotInlining,
+    kValueContext,
+    kEffectContext,
+    kTestContext
+  };
+
   FlowGraph* BuildGraph();
+  FlowGraph* BuildGraphForInlining(InliningContext context);
 
   const ParsedFunction& parsed_function() const { return parsed_function_; }
 
   void Bailout(const char* reason);
 
   void set_context_level(intptr_t value) { context_level_ = value; }
   intptr_t context_level() const { return context_level_; }
 
   // Each try in this function gets its own try index.
   intptr_t AllocateTryIndex() { return ++last_used_try_index_; }
 
   // Manage the currently active try index.
   void set_try_index(intptr_t value) { try_index_ = value; }
   intptr_t try_index() const { return try_index_; }
 
   void AddCatchEntry(TargetEntryInstr* entry);
 
   intptr_t copied_parameter_count() const {
     return copied_parameter_count_;
   }
   intptr_t non_copied_parameter_count() const {
     return non_copied_parameter_count_;
   }
   intptr_t stack_local_count() const {
     return stack_local_count_;
   }
 
+  bool InInliningContext() const { return inlining_context_ != kNotInlining; }
+  void AddReturnExit(ReturnInstr* return_instr) {
+    if (InInliningContext()) {
+      ASSERT(exits_ != NULL);
+      exits_->Add(return_instr);
+    }
+  }
+
  private:
   intptr_t parameter_count() const {
     return copied_parameter_count_ + non_copied_parameter_count_;
   }
   intptr_t variable_count() const {
     return parameter_count() + stack_local_count_;
   }
 
   const ParsedFunction& parsed_function_;
 
   const intptr_t copied_parameter_count_;
   const intptr_t non_copied_parameter_count_;
   const intptr_t stack_local_count_;  // Does not include any parameters.
 
   intptr_t context_level_;
   intptr_t last_used_try_index_;
   intptr_t try_index_;
   GraphEntryInstr* graph_entry_;
+  InliningContext inlining_context_;
+  ZoneGrowableArray<ReturnInstr*>* exits_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(FlowGraphBuilder);
 };
 
 
 class TestGraphVisitor;
 
 // Translate an AstNode to a control-flow graph fragment for its effects
 // (e.g., a statement or an expression in an effect context).  Implements a
 // function from an AstNode and next temporary index to a graph fragment
@@ skipping 17 matching lines @@
 
   FlowGraphBuilder* owner() const { return owner_; }
   intptr_t temp_index() const { return temp_index_; }
   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);
+  void InlineBailout(const char* reason);
 
   // Append a graph fragment to this graph.  Assumes this graph is open.
   void Append(const EffectGraphVisitor& other_fragment);
   // 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-Definition, non-Entry) instruction.  Assumes this
   // graph is open.
   void AddInstruction(Instruction* instruction);
@@ skipping 10 matching lines @@
   // 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);
 
   // Wraps a value in a push-argument instruction and adds the result to the
   // graph.
   PushArgumentInstr* PushArgument(Value* value);
 
+  // This implementation shares state among visitors by using the builder.
+  // The implementation is incorrect if a visitor that hits a return is not
+  // actually added to the graph.
+  void AddReturnExit(ReturnInstr* return_instr) {
+    owner()->AddReturnExit(return_instr);
+  }
+
  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);
   void BuildPushArguments(const ArgumentListNode& node,
                           ZoneGrowableArray<PushArgumentInstr*>* values);
 
@@ skipping 203 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_