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//===-- BitcodeReader.h - ClangDoc Bitcode Reader --------------*- C++ -*-===//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
// 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.
#include "BitcodeWriter.h"
#include "Representation.h"
#include "clang/AST/AST.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/Bitstream/BitstreamReader.h"
#include "llvm/Support/Error.h"
#include <optional>
namespace clang {
namespace doc {
// Class to read bitstream into an InfoSet collection
class ClangDocBitcodeReader {
ClangDocBitcodeReader(llvm::BitstreamCursor &Stream) : Stream(Stream) {}
// Main entry point, calls readBlock to read each block in the given stream.
llvm::Expected<std::vector<std::unique_ptr<Info>>> readBitcode();
enum class Cursor { BadBlock = 1, Record, BlockEnd, BlockBegin };
// Top level parsing
llvm::Error validateStream();
llvm::Error readVersion();
llvm::Error readBlockInfoBlock();
// Read a block of records into a single Info struct, calls readRecord on each
// record found.
template <typename T> llvm::Error readBlock(unsigned ID, T I);
// Step through a block of records to find the next data field.
template <typename T> llvm::Error 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> llvm::Error readRecord(unsigned ID, T I);
// Allocate the relevant type of info and add read data to the object.
template <typename T>
llvm::Expected<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 appropriate type of Info.
llvm::Expected<std::unique_ptr<Info>> readBlockToInfo(unsigned ID);
llvm::BitstreamCursor &Stream;
std::optional<llvm::BitstreamBlockInfo> BlockInfo;
FieldId CurrentReferenceField;
} // namespace doc
} // namespace clang