v8/src/source-position-table.h
Clemens Hammacher d43c6e59fc Decouple SourcePositionTableBuilder from Zone
Currently the SourcePositionTableBuilder requires a Zone because it
holds a ZoneVector<byte> of the encoded entries. Since ZoneVector is a
suboptimal data structure anyway, and for Liftoff we don't even have a
Zone allocated currently, this CL replaces the ZoneVector by
std::vector.

R=mstarzinger@chromium.org

Bug: v8:6600
Change-Id: I8010143e917e2351664e2b53746753b597f4407a
Reviewed-on: https://chromium-review.googlesource.com/779181
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49534}
2017-11-21 12:56:13 +00:00

116 lines
3.1 KiB
C++

// 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_TABLE_H_
#define V8_SOURCE_POSITION_TABLE_H_
#include "src/assert-scope.h"
#include "src/checks.h"
#include "src/globals.h"
#include "src/source-position.h"
#include "src/zone/zone-containers.h"
namespace v8 {
namespace internal {
class ByteArray;
template <typename T>
class Handle;
class Isolate;
class Zone;
struct PositionTableEntry {
PositionTableEntry()
: code_offset(0), source_position(0), is_statement(false) {}
PositionTableEntry(int offset, int64_t source, bool statement)
: code_offset(offset), source_position(source), is_statement(statement) {}
int code_offset;
int64_t source_position;
bool is_statement;
};
class V8_EXPORT_PRIVATE SourcePositionTableBuilder {
public:
enum RecordingMode { OMIT_SOURCE_POSITIONS, RECORD_SOURCE_POSITIONS };
explicit SourcePositionTableBuilder(
RecordingMode mode = RECORD_SOURCE_POSITIONS);
void AddPosition(size_t code_offset, SourcePosition source_position,
bool is_statement);
Handle<ByteArray> ToSourcePositionTable(Isolate* isolate);
private:
void AddEntry(const PositionTableEntry& entry);
inline bool Omit() const { return mode_ == OMIT_SOURCE_POSITIONS; }
RecordingMode mode_;
std::vector<byte> bytes_;
#ifdef ENABLE_SLOW_DCHECKS
std::vector<PositionTableEntry> raw_entries_;
#endif
PositionTableEntry previous_; // Previously written entry, to compute delta.
};
class V8_EXPORT_PRIVATE SourcePositionTableIterator {
public:
// Used for saving/restoring the iterator.
struct IndexAndPosition {
int index_;
PositionTableEntry position_;
};
// We expose two flavours of the iterator, depending on the argument passed
// to the constructor:
// Handlified iterator allows allocation, but it needs a handle (and thus
// a handle scope). This is the preferred version.
explicit SourcePositionTableIterator(Handle<ByteArray> byte_array);
// Non-handlified iterator does not need a handle scope, but it disallows
// allocation during its lifetime. This is useful if there is no handle
// scope around.
explicit SourcePositionTableIterator(ByteArray* byte_array);
void Advance();
int code_offset() const {
DCHECK(!done());
return current_.code_offset;
}
SourcePosition source_position() const {
DCHECK(!done());
return SourcePosition::FromRaw(current_.source_position);
}
bool is_statement() const {
DCHECK(!done());
return current_.is_statement;
}
bool done() const { return index_ == kDone; }
IndexAndPosition GetState() const { return {index_, current_}; }
void RestoreState(const IndexAndPosition& saved_state) {
index_ = saved_state.index_;
current_ = saved_state.position_;
}
private:
static const int kDone = -1;
ByteArray* raw_table_ = nullptr;
Handle<ByteArray> table_;
int index_ = 0;
PositionTableEntry current_;
DisallowHeapAllocation no_gc;
};
} // namespace internal
} // namespace v8
#endif // V8_SOURCE_POSITION_TABLE_H_