| // Copyright 2016 the V8 project authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef V8_SOURCE_POSITION_H_ |
| #define V8_SOURCE_POSITION_H_ |
| |
| #include <ostream> |
| |
| #include "src/assembler.h" |
| #include "src/flags.h" |
| #include "src/utils.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| // This class encapsulates encoding and decoding of sources positions from |
| // which hydrogen values originated. |
| // When FLAG_track_hydrogen_positions is set this object encodes the |
| // identifier of the inlining and absolute offset from the start of the |
| // inlined function. |
| // When the flag is not set we simply track absolute offset from the |
| // script start. |
| class SourcePosition { |
| public: |
| static SourcePosition Unknown() { |
| return SourcePosition::FromRaw(kNoPosition); |
| } |
| |
| bool IsUnknown() const { return value_ == kNoPosition; } |
| |
| uint32_t position() const { return PositionField::decode(value_); } |
| void set_position(uint32_t position) { |
| if (FLAG_hydrogen_track_positions) { |
| value_ = static_cast<uint32_t>(PositionField::update(value_, position)); |
| } else { |
| value_ = position; |
| } |
| } |
| |
| uint32_t inlining_id() const { return InliningIdField::decode(value_); } |
| void set_inlining_id(uint32_t inlining_id) { |
| if (FLAG_hydrogen_track_positions) { |
| value_ = |
| static_cast<uint32_t>(InliningIdField::update(value_, inlining_id)); |
| } |
| } |
| |
| uint32_t raw() const { return value_; } |
| |
| private: |
| static const uint32_t kNoPosition = |
| static_cast<uint32_t>(RelocInfo::kNoPosition); |
| typedef BitField<uint32_t, 0, 9> InliningIdField; |
| |
| // Offset from the start of the inlined function. |
| typedef BitField<uint32_t, 9, 23> PositionField; |
| |
| friend class HPositionInfo; |
| friend class Deoptimizer; |
| |
| static SourcePosition FromRaw(uint32_t raw_position) { |
| SourcePosition position; |
| position.value_ = raw_position; |
| return position; |
| } |
| |
| // If FLAG_hydrogen_track_positions is set contains bitfields InliningIdField |
| // and PositionField. |
| // Otherwise contains absolute offset from the script start. |
| uint32_t value_; |
| }; |
| |
| inline std::ostream& operator<<(std::ostream& os, const SourcePosition& p) { |
| if (p.IsUnknown()) { |
| return os << "<?>"; |
| } else if (FLAG_hydrogen_track_positions) { |
| return os << "<" << p.inlining_id() << ":" << p.position() << ">"; |
| } else { |
| return os << "<0:" << p.raw() << ">"; |
| } |
| } |
| |
| } // namespace internal |
| } // namespace v8 |
| |
| #endif // V8_SOURCE_POSITION_H_ |