diff options
Diffstat (limited to 'contrib/llvm/lib/Support/Compression.cpp')
| -rw-r--r-- | contrib/llvm/lib/Support/Compression.cpp | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Support/Compression.cpp b/contrib/llvm/lib/Support/Compression.cpp new file mode 100644 index 0000000..17ae295 --- /dev/null +++ b/contrib/llvm/lib/Support/Compression.cpp @@ -0,0 +1,98 @@ +//===--- Compression.cpp - Compression implementation ---------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file implements compression functions. +// +//===----------------------------------------------------------------------===// + +#include "llvm/Support/Compression.h" +#include "llvm/ADT/StringRef.h" +#include "llvm/Config/config.h" +#include "llvm/Support/Compiler.h" +#include "llvm/Support/ErrorHandling.h" +#if LLVM_ENABLE_ZLIB == 1 && HAVE_ZLIB_H +#include <zlib.h> +#endif + +using namespace llvm; + +#if LLVM_ENABLE_ZLIB == 1 && HAVE_LIBZ +static int encodeZlibCompressionLevel(zlib::CompressionLevel Level) { + switch (Level) { + case zlib::NoCompression: return 0; + case zlib::BestSpeedCompression: return 1; + case zlib::DefaultCompression: return Z_DEFAULT_COMPRESSION; + case zlib::BestSizeCompression: return 9; + } + llvm_unreachable("Invalid zlib::CompressionLevel!"); +} + +static zlib::Status encodeZlibReturnValue(int ReturnValue) { + switch (ReturnValue) { + case Z_OK: return zlib::StatusOK; + case Z_MEM_ERROR: return zlib::StatusOutOfMemory; + case Z_BUF_ERROR: return zlib::StatusBufferTooShort; + case Z_STREAM_ERROR: return zlib::StatusInvalidArg; + case Z_DATA_ERROR: return zlib::StatusInvalidData; + default: llvm_unreachable("unknown zlib return status!"); + } +} + +bool zlib::isAvailable() { return true; } +zlib::Status zlib::compress(StringRef InputBuffer, + SmallVectorImpl<char> &CompressedBuffer, + CompressionLevel Level) { + unsigned long CompressedSize = ::compressBound(InputBuffer.size()); + CompressedBuffer.resize(CompressedSize); + int CLevel = encodeZlibCompressionLevel(Level); + Status Res = encodeZlibReturnValue(::compress2( + (Bytef *)CompressedBuffer.data(), &CompressedSize, + (const Bytef *)InputBuffer.data(), InputBuffer.size(), CLevel)); + // Tell MemorySanitizer that zlib output buffer is fully initialized. + // This avoids a false report when running LLVM with uninstrumented ZLib. + __msan_unpoison(CompressedBuffer.data(), CompressedSize); + CompressedBuffer.resize(CompressedSize); + return Res; +} + +zlib::Status zlib::uncompress(StringRef InputBuffer, + SmallVectorImpl<char> &UncompressedBuffer, + size_t UncompressedSize) { + UncompressedBuffer.resize(UncompressedSize); + Status Res = encodeZlibReturnValue(::uncompress( + (Bytef *)UncompressedBuffer.data(), (uLongf *)&UncompressedSize, + (const Bytef *)InputBuffer.data(), InputBuffer.size())); + // Tell MemorySanitizer that zlib output buffer is fully initialized. + // This avoids a false report when running LLVM with uninstrumented ZLib. + __msan_unpoison(UncompressedBuffer.data(), UncompressedSize); + UncompressedBuffer.resize(UncompressedSize); + return Res; +} + +uint32_t zlib::crc32(StringRef Buffer) { + return ::crc32(0, (const Bytef *)Buffer.data(), Buffer.size()); +} + +#else +bool zlib::isAvailable() { return false; } +zlib::Status zlib::compress(StringRef InputBuffer, + SmallVectorImpl<char> &CompressedBuffer, + CompressionLevel Level) { + return zlib::StatusUnsupported; +} +zlib::Status zlib::uncompress(StringRef InputBuffer, + SmallVectorImpl<char> &UncompressedBuffer, + size_t UncompressedSize) { + return zlib::StatusUnsupported; +} +uint32_t zlib::crc32(StringRef Buffer) { + llvm_unreachable("zlib::crc32 is unavailable"); +} +#endif + |
