mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-11-22 10:42:39 +01:00
93e240a658
Summary: This patch adds support for ULEB128 and SLEB128 encoding and decoding to BinaryStreamWriter and BinaryStreamReader respectively. Support for ULEB128/SLEB128 will be used for eh-frame parsing in the JITLink library currently under development (see https://reviews.llvm.org/D58704). Reviewers: zturner, dblaikie Subscribers: kristina, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D60810 llvm-svn: 358584
104 lines
3.4 KiB
C++
104 lines
3.4 KiB
C++
//===- BinaryStreamWriter.cpp - Writes objects to a BinaryStream ----------===//
|
|
//
|
|
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
// See https://llvm.org/LICENSE.txt for license information.
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "llvm/Support/BinaryStreamWriter.h"
|
|
|
|
#include "llvm/Support/BinaryStreamError.h"
|
|
#include "llvm/Support/BinaryStreamReader.h"
|
|
#include "llvm/Support/BinaryStreamRef.h"
|
|
#include "llvm/Support/LEB128.h"
|
|
|
|
using namespace llvm;
|
|
|
|
BinaryStreamWriter::BinaryStreamWriter(WritableBinaryStreamRef Ref)
|
|
: Stream(Ref) {}
|
|
|
|
BinaryStreamWriter::BinaryStreamWriter(WritableBinaryStream &Stream)
|
|
: Stream(Stream) {}
|
|
|
|
BinaryStreamWriter::BinaryStreamWriter(MutableArrayRef<uint8_t> Data,
|
|
llvm::support::endianness Endian)
|
|
: Stream(Data, Endian) {}
|
|
|
|
Error BinaryStreamWriter::writeBytes(ArrayRef<uint8_t> Buffer) {
|
|
if (auto EC = Stream.writeBytes(Offset, Buffer))
|
|
return EC;
|
|
Offset += Buffer.size();
|
|
return Error::success();
|
|
}
|
|
|
|
Error BinaryStreamWriter::writeULEB128(uint64_t Value) {
|
|
uint8_t EncodedBytes[10] = {0};
|
|
unsigned Size = encodeULEB128(Value, &EncodedBytes[0]);
|
|
return writeBytes({EncodedBytes, Size});
|
|
}
|
|
|
|
Error BinaryStreamWriter::writeSLEB128(int64_t Value) {
|
|
uint8_t EncodedBytes[10] = {0};
|
|
unsigned Size = encodeSLEB128(Value, &EncodedBytes[0]);
|
|
return writeBytes({EncodedBytes, Size});
|
|
}
|
|
|
|
Error BinaryStreamWriter::writeCString(StringRef Str) {
|
|
if (auto EC = writeFixedString(Str))
|
|
return EC;
|
|
if (auto EC = writeObject('\0'))
|
|
return EC;
|
|
|
|
return Error::success();
|
|
}
|
|
|
|
Error BinaryStreamWriter::writeFixedString(StringRef Str) {
|
|
|
|
return writeBytes(arrayRefFromStringRef(Str));
|
|
}
|
|
|
|
Error BinaryStreamWriter::writeStreamRef(BinaryStreamRef Ref) {
|
|
return writeStreamRef(Ref, Ref.getLength());
|
|
}
|
|
|
|
Error BinaryStreamWriter::writeStreamRef(BinaryStreamRef Ref, uint32_t Length) {
|
|
BinaryStreamReader SrcReader(Ref.slice(0, Length));
|
|
// This is a bit tricky. If we just call readBytes, we are requiring that it
|
|
// return us the entire stream as a contiguous buffer. There is no guarantee
|
|
// this can be satisfied by returning a reference straight from the buffer, as
|
|
// an implementation may not store all data in a single contiguous buffer. So
|
|
// we iterate over each contiguous chunk, writing each one in succession.
|
|
while (SrcReader.bytesRemaining() > 0) {
|
|
ArrayRef<uint8_t> Chunk;
|
|
if (auto EC = SrcReader.readLongestContiguousChunk(Chunk))
|
|
return EC;
|
|
if (auto EC = writeBytes(Chunk))
|
|
return EC;
|
|
}
|
|
return Error::success();
|
|
}
|
|
|
|
std::pair<BinaryStreamWriter, BinaryStreamWriter>
|
|
BinaryStreamWriter::split(uint32_t Off) const {
|
|
assert(getLength() >= Off);
|
|
|
|
WritableBinaryStreamRef First = Stream.drop_front(Offset);
|
|
|
|
WritableBinaryStreamRef Second = First.drop_front(Off);
|
|
First = First.keep_front(Off);
|
|
BinaryStreamWriter W1{First};
|
|
BinaryStreamWriter W2{Second};
|
|
return std::make_pair(W1, W2);
|
|
}
|
|
|
|
Error BinaryStreamWriter::padToAlignment(uint32_t Align) {
|
|
uint32_t NewOffset = alignTo(Offset, Align);
|
|
if (NewOffset > getLength())
|
|
return make_error<BinaryStreamError>(stream_error_code::stream_too_short);
|
|
while (Offset < NewOffset)
|
|
if (auto EC = writeInteger('\0'))
|
|
return EC;
|
|
return Error::success();
|
|
}
|