[llvm] r205677 - Simplify compression API by compressing into a SmallVector rather than a MemoryBuffer
David Blaikie
dblaikie at gmail.com
Sat Apr 5 14:53:05 PDT 2014
Author: dblaikie
Date: Sat Apr 5 16:53:04 2014
New Revision: 205677
URL: http://llvm.org/viewvc/llvm-project?rev=205677&view=rev
Log:
Simplify compression API by compressing into a SmallVector rather than a MemoryBuffer
This is the other half of r205676.
Modified:
llvm/trunk/include/llvm/Support/Compression.h
llvm/trunk/lib/MC/MCAssembler.cpp
llvm/trunk/lib/Support/Compression.cpp
llvm/trunk/unittests/Support/CompressionTest.cpp
Modified: llvm/trunk/include/llvm/Support/Compression.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Support/Compression.h?rev=205677&r1=205676&r2=205677&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Support/Compression.h (original)
+++ llvm/trunk/include/llvm/Support/Compression.h Sat Apr 5 16:53:04 2014
@@ -20,7 +20,6 @@
namespace llvm {
-class MemoryBuffer;
class StringRef;
namespace zlib {
@@ -43,8 +42,7 @@ enum Status {
bool isAvailable();
-Status compress(StringRef InputBuffer,
- std::unique_ptr<MemoryBuffer> &CompressedBuffer,
+Status compress(StringRef InputBuffer, SmallVectorImpl<char> &CompressedBuffer,
CompressionLevel Level = DefaultCompression);
Status uncompress(StringRef InputBuffer,
Modified: llvm/trunk/lib/MC/MCAssembler.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCAssembler.cpp?rev=205677&r1=205676&r2=205677&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCAssembler.cpp (original)
+++ llvm/trunk/lib/MC/MCAssembler.cpp Sat Apr 5 16:53:04 2014
@@ -237,23 +237,23 @@ const SmallVectorImpl<char> &MCCompresse
assert(getParent()->size() == 1 &&
"Only compress sections containing a single fragment");
if (CompressedContents.empty()) {
- std::unique_ptr<MemoryBuffer> CompressedSection;
+ // FIXME: could be more efficient if we let zlib::compress append to a
+ // buffer rather than always from the start.
zlib::Status Success =
zlib::compress(StringRef(getContents().data(), getContents().size()),
- CompressedSection);
+ CompressedContents);
(void)Success;
assert(Success == zlib::StatusOK);
- CompressedContents.push_back('Z');
- CompressedContents.push_back('L');
- CompressedContents.push_back('I');
- CompressedContents.push_back('B');
+ static const StringRef Magic = "ZLIB";
uint64_t Size = getContents().size();
if (sys::IsLittleEndianHost)
Size = sys::SwapByteOrder(Size);
- CompressedContents.append(reinterpret_cast<char *>(&Size),
- reinterpret_cast<char *>(&Size + 1));
- CompressedContents.append(CompressedSection->getBuffer().begin(),
- CompressedSection->getBuffer().end());
+ CompressedContents.insert(CompressedContents.begin(),
+ Magic.size() + sizeof(Size));
+ std::copy(Magic.begin(), Magic.end(), CompressedContents.begin());
+ std::copy(reinterpret_cast<char *>(&Size),
+ reinterpret_cast<char *>(&Size + 1),
+ CompressedContents.begin() + Magic.size());
}
return CompressedContents;
}
Modified: llvm/trunk/lib/Support/Compression.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/Compression.cpp?rev=205677&r1=205676&r2=205677&view=diff
==============================================================================
--- llvm/trunk/lib/Support/Compression.cpp (original)
+++ llvm/trunk/lib/Support/Compression.cpp Sat Apr 5 16:53:04 2014
@@ -16,7 +16,6 @@
#include "llvm/Config/config.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/ErrorHandling.h"
-#include "llvm/Support/MemoryBuffer.h"
#if LLVM_ENABLE_ZLIB == 1 && HAVE_ZLIB_H
#include <zlib.h>
#endif
@@ -47,20 +46,15 @@ static zlib::Status encodeZlibReturnValu
bool zlib::isAvailable() { return true; }
zlib::Status zlib::compress(StringRef InputBuffer,
- std::unique_ptr<MemoryBuffer> &CompressedBuffer,
+ SmallVectorImpl<char> &CompressedBuffer,
CompressionLevel Level) {
unsigned long CompressedSize = ::compressBound(InputBuffer.size());
- std::unique_ptr<char[]> TmpBuffer(new char[CompressedSize]);
+ CompressedBuffer.resize(CompressedSize);
int CLevel = encodeZlibCompressionLevel(Level);
Status Res = encodeZlibReturnValue(::compress2(
- (Bytef *)TmpBuffer.get(), &CompressedSize,
+ (Bytef *)CompressedBuffer.data(), &CompressedSize,
(const Bytef *)InputBuffer.data(), InputBuffer.size(), CLevel));
- if (Res == StatusOK) {
- CompressedBuffer.reset(MemoryBuffer::getMemBufferCopy(
- StringRef(TmpBuffer.get(), CompressedSize)));
- // Tell MSan that memory initialized by zlib is valid.
- __msan_unpoison(CompressedBuffer->getBufferStart(), CompressedSize);
- }
+ CompressedBuffer.resize(CompressedSize);
return Res;
}
@@ -82,12 +76,12 @@ uint32_t zlib::crc32(StringRef Buffer) {
#else
bool zlib::isAvailable() { return false; }
zlib::Status zlib::compress(StringRef InputBuffer,
- std::unique_ptr<MemoryBuffer> &CompressedBuffer,
+ SmallVectorImpl<char> &CompressedBuffer,
CompressionLevel Level) {
return zlib::StatusUnsupported;
}
zlib::Status zlib::uncompress(StringRef InputBuffer,
- std::unique_ptr<MemoryBuffer> &UncompressedBuffer,
+ SmallVectorImpl<char> &UncompressedBuffer,
size_t UncompressedSize) {
return zlib::StatusUnsupported;
}
Modified: llvm/trunk/unittests/Support/CompressionTest.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/unittests/Support/CompressionTest.cpp?rev=205677&r1=205676&r2=205677&view=diff
==============================================================================
--- llvm/trunk/unittests/Support/CompressionTest.cpp (original)
+++ llvm/trunk/unittests/Support/CompressionTest.cpp Sat Apr 5 16:53:04 2014
@@ -13,8 +13,8 @@
#include "llvm/Support/Compression.h"
#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/SmallString.h"
#include "llvm/Config/config.h"
-#include "llvm/Support/MemoryBuffer.h"
#include "gtest/gtest.h"
using namespace llvm;
@@ -24,19 +24,17 @@ namespace {
#if LLVM_ENABLE_ZLIB == 1 && HAVE_LIBZ
void TestZlibCompression(StringRef Input, zlib::CompressionLevel Level) {
- std::unique_ptr<MemoryBuffer> Compressed;
+ SmallString<32> Compressed;
SmallString<32> Uncompressed;
EXPECT_EQ(zlib::StatusOK, zlib::compress(Input, Compressed, Level));
// Check that uncompressed buffer is the same as original.
- EXPECT_EQ(zlib::StatusOK, zlib::uncompress(Compressed->getBuffer(),
- Uncompressed, Input.size()));
- EXPECT_EQ(Input.size(), Uncompressed.size());
- EXPECT_EQ(0, memcmp(Input.data(), Uncompressed.data(), Input.size()));
+ EXPECT_EQ(zlib::StatusOK,
+ zlib::uncompress(Compressed, Uncompressed, Input.size()));
+ EXPECT_EQ(Input, Uncompressed);
if (Input.size() > 0) {
// Uncompression fails if expected length is too short.
EXPECT_EQ(zlib::StatusBufferTooShort,
- zlib::uncompress(Compressed->getBuffer(), Uncompressed,
- Input.size() - 1));
+ zlib::uncompress(Compressed, Uncompressed, Input.size() - 1));
}
}
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