Home | History | Annotate | Download | only in interpreter 
      1 // Copyright 2016 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_INTERPRETER_SOURCE_POSITION_TABLE_H_
      6 #define V8_INTERPRETER_SOURCE_POSITION_TABLE_H_
      7 
      8 #include "src/assert-scope.h"
      9 #include "src/checks.h"
     10 #include "src/handles.h"
     11 #include "src/log.h"
     12 #include "src/zone-containers.h"
     13 
     14 namespace v8 {
     15 namespace internal {
     16 
     17 class BytecodeArray;
     18 class ByteArray;
     19 class Isolate;
     20 class Zone;
     21 
     22 namespace interpreter {
     23 
     24 struct PositionTableEntry {
     25   PositionTableEntry()
     26       : bytecode_offset(0), source_position(0), is_statement(false) {}
     27   PositionTableEntry(int bytecode, int source, bool statement)
     28       : bytecode_offset(bytecode),
     29         source_position(source),
     30         is_statement(statement) {}
     31 
     32   int bytecode_offset;
     33   int source_position;
     34   bool is_statement;
     35 };
     36 
     37 class SourcePositionTableBuilder final : public PositionsRecorder {
     38  public:
     39   SourcePositionTableBuilder(Isolate* isolate, Zone* zone)
     40       : isolate_(isolate),
     41         bytes_(zone),
     42 #ifdef ENABLE_SLOW_DCHECKS
     43         raw_entries_(zone),
     44 #endif
     45         previous_() {
     46   }
     47 
     48   void AddPosition(size_t bytecode_offset, int source_position,
     49                    bool is_statement);
     50   Handle<ByteArray> ToSourcePositionTable();
     51 
     52  private:
     53   void AddEntry(const PositionTableEntry& entry);
     54   void CommitEntry();
     55 
     56   Isolate* isolate_;
     57   ZoneVector<byte> bytes_;
     58 #ifdef ENABLE_SLOW_DCHECKS
     59   ZoneVector<PositionTableEntry> raw_entries_;
     60 #endif
     61   PositionTableEntry previous_;   // Previously written entry, to compute delta.
     62 };
     63 
     64 class SourcePositionTableIterator {
     65  public:
     66   explicit SourcePositionTableIterator(ByteArray* byte_array);
     67 
     68   void Advance();
     69 
     70   int bytecode_offset() const {
     71     DCHECK(!done());
     72     return current_.bytecode_offset;
     73   }
     74   int source_position() const {
     75     DCHECK(!done());
     76     return current_.source_position;
     77   }
     78   bool is_statement() const {
     79     DCHECK(!done());
     80     return current_.is_statement;
     81   }
     82   bool done() const { return index_ == kDone; }
     83 
     84  private:
     85   static const int kDone = -1;
     86 
     87   ByteArray* table_;
     88   int index_;
     89   PositionTableEntry current_;
     90   DisallowHeapAllocation no_gc;
     91 };
     92 
     93 }  // namespace interpreter
     94 }  // namespace internal
     95 }  // namespace v8
     96 
     97 #endif  // V8_INTERPRETER_SOURCE_POSITION_TABLE_H_
     98