Recognize leaf functions: skip stack check and populating the pc slot, store the pc slot lazily in …

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
@@ skipping 10 matching lines @@
   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);
+                    bool is_optimizing,
+                    bool is_leaf);
 
   ~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 {
@@ skipping 213 matching lines @@
   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;
   }
 
+  // Returns true if the generated code does not call other Dart code.

[regis, 2012/06/25 23:46:09]

ditto

[srdjan, 2012/06/25 23:50:22]

Done.

+  // Only deoptimization is allowed to occur. Closures are not leaf.
+  bool IsLeaf() const;
+
   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 is_dart_leaf_;
 
   const Bool& bool_true_;
   const Bool& bool_false_;
   const Class& double_class_;
 
   FrameRegisterAllocator frame_register_allocator_;
 
   DISALLOW_COPY_AND_ASSIGN(FlowGraphCompiler);
 };
 
@@ skipping 24 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_