1 // Copyright 2013 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #ifndef V8_HYDROGEN_OSR_H_
6 #define V8_HYDROGEN_OSR_H_
7 
8 #include "src/hydrogen.h"
9 #include "src/ast.h"
10 #include "src/zone.h"
11 
12 namespace v8 {
13 namespace internal {
14 
15 // Responsible for building graph parts related to OSR and otherwise
16 // setting up the graph to do an OSR compile.
17 class HOsrBuilder : public ZoneObject {
18  public:
HOsrBuilder(HOptimizedGraphBuilder * builder)19   explicit HOsrBuilder(HOptimizedGraphBuilder* builder)
20     : unoptimized_frame_slots_(0),
21       builder_(builder),
22       osr_entry_(NULL),
23       osr_loop_entry_(NULL),
24       osr_values_(NULL) { }
25 
26   // Creates the loop entry block for the given statement, setting up OSR
27   // entries as necessary, and sets the current block to the new block.
28   HBasicBlock* BuildOsrLoopEntry(IterationStatement* statement);
29 
30   // Process the hydrogen graph after it has been completed, performing
31   // any OSR-specific cleanups or changes.
32   void FinishGraph();
33 
34   // Process the OSR values and phis after initial graph optimization.
35   void FinishOsrValues();
36 
37   // Return the number of slots in the unoptimized frame at the entry to OSR.
UnoptimizedFrameSlots()38   int UnoptimizedFrameSlots() const {
39     return unoptimized_frame_slots_;
40   }
41 
42   bool HasOsrEntryAt(IterationStatement* statement);
43 
44  private:
45   int unoptimized_frame_slots_;
46   HOptimizedGraphBuilder* builder_;
47   HBasicBlock* osr_entry_;
48   HBasicBlock* osr_loop_entry_;
49   ZoneList<HUnknownOSRValue*>* osr_values_;
50 };
51 
52 } }  // namespace v8::internal
53 
54 #endif  // V8_HYDROGEN_OSR_H_
55