diff options
Diffstat (limited to 'contrib/llvm/lib/DebugInfo/PDB/Raw/MappedBlockStream.cpp')
-rw-r--r-- | contrib/llvm/lib/DebugInfo/PDB/Raw/MappedBlockStream.cpp | 310 |
1 files changed, 0 insertions, 310 deletions
diff --git a/contrib/llvm/lib/DebugInfo/PDB/Raw/MappedBlockStream.cpp b/contrib/llvm/lib/DebugInfo/PDB/Raw/MappedBlockStream.cpp deleted file mode 100644 index 92b2048..0000000 --- a/contrib/llvm/lib/DebugInfo/PDB/Raw/MappedBlockStream.cpp +++ /dev/null @@ -1,310 +0,0 @@ -//===- MappedBlockStream.cpp - Reads stream data from a PDBFile -----------===// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// - -#include "llvm/DebugInfo/PDB/Raw/MappedBlockStream.h" -#include "llvm/DebugInfo/PDB/Raw/DirectoryStreamData.h" -#include "llvm/DebugInfo/PDB/Raw/IPDBStreamData.h" -#include "llvm/DebugInfo/PDB/Raw/IndexedStreamData.h" -#include "llvm/DebugInfo/PDB/Raw/PDBFile.h" -#include "llvm/DebugInfo/PDB/Raw/RawError.h" - -using namespace llvm; -using namespace llvm::pdb; - -namespace { -// This exists so that we can use make_unique while still keeping the -// constructor of MappedBlockStream private, forcing users to go through -// the `create` interface. -class MappedBlockStreamImpl : public MappedBlockStream { -public: - MappedBlockStreamImpl(std::unique_ptr<IPDBStreamData> Data, - const IPDBFile &File) - : MappedBlockStream(std::move(Data), File) {} -}; -} - -typedef std::pair<uint32_t, uint32_t> Interval; -static Interval intersect(const Interval &I1, const Interval &I2) { - return std::make_pair(std::max(I1.first, I2.first), - std::min(I1.second, I2.second)); -} - -MappedBlockStream::MappedBlockStream(std::unique_ptr<IPDBStreamData> Data, - const IPDBFile &Pdb) - : Pdb(Pdb), Data(std::move(Data)) {} - -Error MappedBlockStream::readBytes(uint32_t Offset, uint32_t Size, - ArrayRef<uint8_t> &Buffer) const { - // Make sure we aren't trying to read beyond the end of the stream. - if (Size > Data->getLength()) - return make_error<RawError>(raw_error_code::insufficient_buffer); - if (Offset > Data->getLength() - Size) - return make_error<RawError>(raw_error_code::insufficient_buffer); - - if (tryReadContiguously(Offset, Size, Buffer)) - return Error::success(); - - auto CacheIter = CacheMap.find(Offset); - if (CacheIter != CacheMap.end()) { - // Try to find an alloc that was large enough for this request. - for (auto &Entry : CacheIter->second) { - if (Entry.size() >= Size) { - Buffer = Entry.slice(0, Size); - return Error::success(); - } - } - } - - // We couldn't find a buffer that started at the correct offset (the most - // common scenario). Try to see if there is a buffer that starts at some - // other offset but overlaps the desired range. - for (auto &CacheItem : CacheMap) { - Interval RequestExtent = std::make_pair(Offset, Offset + Size); - - // We already checked this one on the fast path above. - if (CacheItem.first == Offset) - continue; - // If the initial extent of the cached item is beyond the ending extent - // of the request, there is no overlap. - if (CacheItem.first >= Offset + Size) - continue; - - // We really only have to check the last item in the list, since we append - // in order of increasing length. - if (CacheItem.second.empty()) - continue; - - auto CachedAlloc = CacheItem.second.back(); - // If the initial extent of the request is beyond the ending extent of - // the cached item, there is no overlap. - Interval CachedExtent = - std::make_pair(CacheItem.first, CacheItem.first + CachedAlloc.size()); - if (RequestExtent.first >= CachedExtent.first + CachedExtent.second) - continue; - - Interval Intersection = intersect(CachedExtent, RequestExtent); - // Only use this if the entire request extent is contained in the cached - // extent. - if (Intersection != RequestExtent) - continue; - - uint32_t CacheRangeOffset = - AbsoluteDifference(CachedExtent.first, Intersection.first); - Buffer = CachedAlloc.slice(CacheRangeOffset, Size); - return Error::success(); - } - - // Otherwise allocate a large enough buffer in the pool, memcpy the data - // into it, and return an ArrayRef to that. Do not touch existing pool - // allocations, as existing clients may be holding a pointer which must - // not be invalidated. - uint8_t *WriteBuffer = static_cast<uint8_t *>(Pool.Allocate(Size, 8)); - if (auto EC = readBytes(Offset, MutableArrayRef<uint8_t>(WriteBuffer, Size))) - return EC; - - if (CacheIter != CacheMap.end()) { - CacheIter->second.emplace_back(WriteBuffer, Size); - } else { - std::vector<CacheEntry> List; - List.emplace_back(WriteBuffer, Size); - CacheMap.insert(std::make_pair(Offset, List)); - } - Buffer = ArrayRef<uint8_t>(WriteBuffer, Size); - return Error::success(); -} - -Error MappedBlockStream::readLongestContiguousChunk( - uint32_t Offset, ArrayRef<uint8_t> &Buffer) const { - // Make sure we aren't trying to read beyond the end of the stream. - if (Offset >= Data->getLength()) - return make_error<RawError>(raw_error_code::insufficient_buffer); - uint32_t First = Offset / Pdb.getBlockSize(); - uint32_t Last = First; - - auto BlockList = Data->getStreamBlocks(); - while (Last < Pdb.getBlockCount() - 1) { - if (BlockList[Last] != BlockList[Last + 1] - 1) - break; - ++Last; - } - - uint32_t OffsetInFirstBlock = Offset % Pdb.getBlockSize(); - uint32_t BytesFromFirstBlock = Pdb.getBlockSize() - OffsetInFirstBlock; - uint32_t BlockSpan = Last - First + 1; - uint32_t ByteSpan = - BytesFromFirstBlock + (BlockSpan - 1) * Pdb.getBlockSize(); - auto Result = Pdb.getBlockData(BlockList[First], Pdb.getBlockSize()); - if (!Result) - return Result.takeError(); - Buffer = Result->drop_front(OffsetInFirstBlock); - Buffer = ArrayRef<uint8_t>(Buffer.data(), ByteSpan); - return Error::success(); -} - -uint32_t MappedBlockStream::getLength() const { return Data->getLength(); } - -Error MappedBlockStream::commit() const { return Error::success(); } - -bool MappedBlockStream::tryReadContiguously(uint32_t Offset, uint32_t Size, - ArrayRef<uint8_t> &Buffer) const { - // Attempt to fulfill the request with a reference directly into the stream. - // This can work even if the request crosses a block boundary, provided that - // all subsequent blocks are contiguous. For example, a 10k read with a 4k - // block size can be filled with a reference if, from the starting offset, - // 3 blocks in a row are contiguous. - uint32_t BlockNum = Offset / Pdb.getBlockSize(); - uint32_t OffsetInBlock = Offset % Pdb.getBlockSize(); - uint32_t BytesFromFirstBlock = - std::min(Size, Pdb.getBlockSize() - OffsetInBlock); - uint32_t NumAdditionalBlocks = - llvm::alignTo(Size - BytesFromFirstBlock, Pdb.getBlockSize()) / - Pdb.getBlockSize(); - - auto BlockList = Data->getStreamBlocks(); - uint32_t RequiredContiguousBlocks = NumAdditionalBlocks + 1; - uint32_t E = BlockList[BlockNum]; - for (uint32_t I = 0; I < RequiredContiguousBlocks; ++I, ++E) { - if (BlockList[I + BlockNum] != E) - return false; - } - - uint32_t FirstBlockAddr = BlockList[BlockNum]; - auto Result = Pdb.getBlockData(FirstBlockAddr, Pdb.getBlockSize()); - if (!Result) { - consumeError(Result.takeError()); - return false; - } - auto Data = Result->drop_front(OffsetInBlock); - Buffer = ArrayRef<uint8_t>(Data.data(), Size); - return true; -} - -Error MappedBlockStream::readBytes(uint32_t Offset, - MutableArrayRef<uint8_t> Buffer) const { - uint32_t BlockNum = Offset / Pdb.getBlockSize(); - uint32_t OffsetInBlock = Offset % Pdb.getBlockSize(); - - // Make sure we aren't trying to read beyond the end of the stream. - if (Buffer.size() > Data->getLength()) - return make_error<RawError>(raw_error_code::insufficient_buffer); - if (Offset > Data->getLength() - Buffer.size()) - return make_error<RawError>(raw_error_code::insufficient_buffer); - - uint32_t BytesLeft = Buffer.size(); - uint32_t BytesWritten = 0; - uint8_t *WriteBuffer = Buffer.data(); - auto BlockList = Data->getStreamBlocks(); - while (BytesLeft > 0) { - uint32_t StreamBlockAddr = BlockList[BlockNum]; - - auto Result = Pdb.getBlockData(StreamBlockAddr, Pdb.getBlockSize()); - if (!Result) - return Result.takeError(); - - auto Data = *Result; - const uint8_t *ChunkStart = Data.data() + OffsetInBlock; - uint32_t BytesInChunk = - std::min(BytesLeft, Pdb.getBlockSize() - OffsetInBlock); - ::memcpy(WriteBuffer + BytesWritten, ChunkStart, BytesInChunk); - - BytesWritten += BytesInChunk; - BytesLeft -= BytesInChunk; - ++BlockNum; - OffsetInBlock = 0; - } - - return Error::success(); -} - -Error MappedBlockStream::writeBytes(uint32_t Offset, - ArrayRef<uint8_t> Buffer) const { - // Make sure we aren't trying to write beyond the end of the stream. - if (Buffer.size() > Data->getLength()) - return make_error<RawError>(raw_error_code::insufficient_buffer); - - if (Offset > Data->getLength() - Buffer.size()) - return make_error<RawError>(raw_error_code::insufficient_buffer); - - uint32_t BlockNum = Offset / Pdb.getBlockSize(); - uint32_t OffsetInBlock = Offset % Pdb.getBlockSize(); - - uint32_t BytesLeft = Buffer.size(); - auto BlockList = Data->getStreamBlocks(); - uint32_t BytesWritten = 0; - while (BytesLeft > 0) { - uint32_t StreamBlockAddr = BlockList[BlockNum]; - uint32_t BytesToWriteInChunk = - std::min(BytesLeft, Pdb.getBlockSize() - OffsetInBlock); - - const uint8_t *Chunk = Buffer.data() + BytesWritten; - ArrayRef<uint8_t> ChunkData(Chunk, BytesToWriteInChunk); - if (auto EC = Pdb.setBlockData(StreamBlockAddr, OffsetInBlock, ChunkData)) - return EC; - - BytesLeft -= BytesToWriteInChunk; - BytesWritten += BytesToWriteInChunk; - ++BlockNum; - OffsetInBlock = 0; - } - - // If this write overlapped a read which previously came from the pool, - // someone may still be holding a pointer to that alloc which is now invalid. - // Compute the overlapping range and update the cache entry, so any - // outstanding buffers are automatically updated. - for (const auto &MapEntry : CacheMap) { - // If the end of the written extent precedes the beginning of the cached - // extent, ignore this map entry. - if (Offset + BytesWritten < MapEntry.first) - continue; - for (const auto &Alloc : MapEntry.second) { - // If the end of the cached extent precedes the beginning of the written - // extent, ignore this alloc. - if (MapEntry.first + Alloc.size() < Offset) - continue; - - // If we get here, they are guaranteed to overlap. - Interval WriteInterval = std::make_pair(Offset, Offset + BytesWritten); - Interval CachedInterval = - std::make_pair(MapEntry.first, MapEntry.first + Alloc.size()); - // If they overlap, we need to write the new data into the overlapping - // range. - auto Intersection = intersect(WriteInterval, CachedInterval); - assert(Intersection.first <= Intersection.second); - - uint32_t Length = Intersection.second - Intersection.first; - uint32_t SrcOffset = - AbsoluteDifference(WriteInterval.first, Intersection.first); - uint32_t DestOffset = - AbsoluteDifference(CachedInterval.first, Intersection.first); - ::memcpy(Alloc.data() + DestOffset, Buffer.data() + SrcOffset, Length); - } - } - - return Error::success(); -} - -uint32_t MappedBlockStream::getNumBytesCopied() const { - return static_cast<uint32_t>(Pool.getBytesAllocated()); -} - -Expected<std::unique_ptr<MappedBlockStream>> -MappedBlockStream::createIndexedStream(uint32_t StreamIdx, - const IPDBFile &File) { - if (StreamIdx >= File.getNumStreams()) - return make_error<RawError>(raw_error_code::no_stream); - - auto Data = llvm::make_unique<IndexedStreamData>(StreamIdx, File); - return llvm::make_unique<MappedBlockStreamImpl>(std::move(Data), File); -} - -Expected<std::unique_ptr<MappedBlockStream>> -MappedBlockStream::createDirectoryStream(const PDBFile &File) { - auto Data = llvm::make_unique<DirectoryStreamData>(File); - return llvm::make_unique<MappedBlockStreamImpl>(std::move(Data), File); -} |