llvm-project/clang-tools-extra/clang-doc/BitcodeReader.h

74 lines
2.5 KiB
C++

//===-- BitcodeReader.h - ClangDoc Bitcode Reader --------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements a reader for parsing the clang-doc internal
// representation from LLVM bitcode. The reader takes in a stream of bits and
// generates the set of infos that it represents.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_DOC_BITCODEREADER_H
#define LLVM_CLANG_TOOLS_EXTRA_CLANG_DOC_BITCODEREADER_H
#include "BitcodeWriter.h"
#include "Representation.h"
#include "clang/AST/AST.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/Bitcode/BitstreamReader.h"
namespace clang {
namespace doc {
// Class to read bitstream into an InfoSet collection
class ClangDocBitcodeReader {
public:
ClangDocBitcodeReader(llvm::BitstreamCursor &Stream) : Stream(Stream) {}
// Main entry point, calls readBlock to read each block in the given stream.
std::vector<std::unique_ptr<Info>> readBitcode();
private:
enum class Cursor { BadBlock = 1, Record, BlockEnd, BlockBegin };
// Top level parsing
bool validateStream();
bool readVersion();
bool readBlockInfoBlock();
// Read a block of records into a single Info struct, calls readRecord on each
// record found.
template <typename T> bool readBlock(unsigned ID, T I);
// Step through a block of records to find the next data field.
template <typename T> bool readSubBlock(unsigned ID, T I);
// Read record data into the given Info data field, calling the appropriate
// parseRecord functions to parse and store the data.
template <typename T> bool readRecord(unsigned ID, T I);
// Allocate the relevant type of info and add read data to the object.
template <typename T> std::unique_ptr<Info> createInfo(unsigned ID);
// Helper function to step through blocks to find and dispatch the next record
// or block to be read.
Cursor skipUntilRecordOrBlock(unsigned &BlockOrRecordID);
// Helper function to set up the approriate type of Info.
std::unique_ptr<Info> readBlockToInfo(unsigned ID);
llvm::BitstreamCursor &Stream;
Optional<llvm::BitstreamBlockInfo> BlockInfo;
FieldId CurrentReferenceField;
};
} // namespace doc
} // namespace clang
#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_DOC_BITCODEREADER_H