[llvm-commits] [llvm] r127413 - in /llvm/trunk: include/llvm/Support/MemoryBuffer.h include/llvm/Support/PathV1.h lib/Support/MemoryBuffer.cpp lib/Support/Unix/Path.inc
Jakob Stoklund Olesen
stoklund at 2pi.dk
Thu Mar 10 10:01:43 PST 2011
Author: stoklund
Date: Thu Mar 10 12:01:43 2011
New Revision: 127413
URL: http://llvm.org/viewvc/llvm-project?rev=127413&view=rev
Log:
Revert r127409 which broke all the Windows bots.
Modified:
llvm/trunk/include/llvm/Support/MemoryBuffer.h
llvm/trunk/include/llvm/Support/PathV1.h
llvm/trunk/lib/Support/MemoryBuffer.cpp
llvm/trunk/lib/Support/Unix/Path.inc
Modified: llvm/trunk/include/llvm/Support/MemoryBuffer.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Support/MemoryBuffer.h?rev=127413&r1=127412&r2=127413&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Support/MemoryBuffer.h (original)
+++ llvm/trunk/include/llvm/Support/MemoryBuffer.h Thu Mar 10 12:01:43 2011
@@ -40,8 +40,7 @@
MemoryBuffer &operator=(const MemoryBuffer &); // DO NOT IMPLEMENT
protected:
MemoryBuffer() {}
- void init(const char *BufStart, const char *BufEnd,
- bool RequiresNullTerminator);
+ void init(const char *BufStart, const char *BufEnd);
public:
virtual ~MemoryBuffer();
@@ -73,10 +72,7 @@
/// return a MemoryBuffer.
static error_code getOpenFile(int FD, const char *Filename,
OwningPtr<MemoryBuffer> &result,
- size_t FileSize = -1,
- size_t MapSize = -1,
- off_t Offset = 0,
- bool RequiresNullTerminator = true);
+ int64_t FileSize = -1);
/// getMemBuffer - Open the specified memory range as a MemoryBuffer. Note
/// that InputData must be null terminated.
Modified: llvm/trunk/include/llvm/Support/PathV1.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Support/PathV1.h?rev=127413&r1=127412&r2=127413&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Support/PathV1.h (original)
+++ llvm/trunk/include/llvm/Support/PathV1.h Thu Mar 10 12:01:43 2011
@@ -608,15 +608,14 @@
///
/// This API is not intended for general use, clients should use
/// MemoryBuffer::getFile instead.
- static const char *MapInFilePages(int FD, size_t FileSize,
- off_t Offset);
+ static const char *MapInFilePages(int FD, uint64_t FileSize);
/// UnMapFilePages - Free pages mapped into the current process by
/// MapInFilePages.
///
/// This API is not intended for general use, clients should use
/// MemoryBuffer::getFile instead.
- static void UnMapFilePages(const char *Base, size_t FileSize);
+ static void UnMapFilePages(const char *Base, uint64_t FileSize);
/// @}
/// @name Data
Modified: llvm/trunk/lib/Support/MemoryBuffer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/MemoryBuffer.cpp?rev=127413&r1=127412&r2=127413&view=diff
==============================================================================
--- llvm/trunk/lib/Support/MemoryBuffer.cpp (original)
+++ llvm/trunk/lib/Support/MemoryBuffer.cpp Thu Mar 10 12:01:43 2011
@@ -46,10 +46,8 @@
/// init - Initialize this MemoryBuffer as a reference to externally allocated
/// memory, memory that we know is already null terminated.
-void MemoryBuffer::init(const char *BufStart, const char *BufEnd,
- bool RequiresNullTerminator) {
- assert((BufEnd[0] == 0 || !RequiresNullTerminator) &&
- "Buffer is not null terminated!");
+void MemoryBuffer::init(const char *BufStart, const char *BufEnd) {
+ assert(BufEnd[0] == 0 && "Buffer is not null terminated!");
BufferStart = BufStart;
BufferEnd = BufEnd;
}
@@ -67,19 +65,18 @@
/// GetNamedBuffer - Allocates a new MemoryBuffer with Name copied after it.
template <typename T>
-static T* GetNamedBuffer(StringRef Buffer, StringRef Name,
- bool RequiresNullTerminator) {
+static T* GetNamedBuffer(StringRef Buffer, StringRef Name) {
char *Mem = static_cast<char*>(operator new(sizeof(T) + Name.size() + 1));
CopyStringRef(Mem + sizeof(T), Name);
- return new (Mem) T(Buffer, RequiresNullTerminator);
+ return new (Mem) T(Buffer);
}
namespace {
/// MemoryBufferMem - Named MemoryBuffer pointing to a block of memory.
class MemoryBufferMem : public MemoryBuffer {
public:
- MemoryBufferMem(StringRef InputData, bool RequiresNullTerminator) {
- init(InputData.begin(), InputData.end(), RequiresNullTerminator);
+ MemoryBufferMem(StringRef InputData) {
+ init(InputData.begin(), InputData.end());
}
virtual const char *getBufferIdentifier() const {
@@ -93,7 +90,7 @@
/// that EndPtr[0] must be a null byte and be accessible!
MemoryBuffer *MemoryBuffer::getMemBuffer(StringRef InputData,
StringRef BufferName) {
- return GetNamedBuffer<MemoryBufferMem>(InputData, BufferName, true);
+ return GetNamedBuffer<MemoryBufferMem>(InputData, BufferName);
}
/// getMemBufferCopy - Open the specified memory range as a MemoryBuffer,
@@ -130,7 +127,7 @@
char *Buf = Mem + AlignedStringLen;
Buf[Size] = 0; // Null terminate buffer.
- return new (Mem) MemoryBufferMem(StringRef(Buf, Size), true);
+ return new (Mem) MemoryBufferMem(StringRef(Buf, Size));
}
/// getNewMemBuffer - Allocate a new MemoryBuffer of the specified size that
@@ -175,19 +172,11 @@
/// sys::Path::UnMapFilePages method.
class MemoryBufferMMapFile : public MemoryBufferMem {
public:
- MemoryBufferMMapFile(StringRef Buffer, bool RequiresNullTerminator)
- : MemoryBufferMem(Buffer, RequiresNullTerminator) { }
+ MemoryBufferMMapFile(StringRef Buffer)
+ : MemoryBufferMem(Buffer) { }
~MemoryBufferMMapFile() {
- static int PageSize = sys::Process::GetPageSize();
-
- uintptr_t Start = reinterpret_cast<uintptr_t>(getBufferStart());
- size_t Size = getBufferSize();
- uintptr_t RealStart = Start & ~(PageSize - 1);
- size_t RealSize = Size + (Start - RealStart);
-
- sys::Path::UnMapFilePages(reinterpret_cast<const char*>(RealStart),
- RealSize);
+ sys::Path::UnMapFilePages(getBufferStart(), getBufferSize());
}
};
}
@@ -216,44 +205,12 @@
return ret;
}
-static bool shouldUseMmap(size_t FileSize,
- size_t MapSize,
- off_t Offset,
- bool RequiresNullTerminator,
- int PageSize) {
- // We don't use mmap for small files because this can severely fragment our
- // address space.
- if (MapSize < 4096*4)
- return false;
-
- if (!RequiresNullTerminator)
- return true;
-
- // If we need a null terminator and the end of the map is inside the file,
- // we cannot use mmap.
- size_t End = Offset + MapSize;
- assert(End <= FileSize);
- if (End != FileSize)
- return false;
-
- // Don't try to map files that are exactly a multiple of the system page size
- // if we need a null terminator.
- if ((FileSize & (PageSize -1)) == 0)
- return false;
-
- return true;
-}
-
error_code MemoryBuffer::getOpenFile(int FD, const char *Filename,
OwningPtr<MemoryBuffer> &result,
- size_t FileSize, size_t MapSize,
- off_t Offset,
- bool RequiresNullTerminator) {
- static int PageSize = sys::Process::GetPageSize();
-
+ int64_t FileSize) {
// If we don't know the file size, use fstat to find out. fstat on an open
// file descriptor is cheaper than stat on a random path.
- if (FileSize == size_t(-1)) {
+ if (FileSize == -1) {
struct stat FileInfo;
// TODO: This should use fstat64 when available.
if (fstat(FD, &FileInfo) == -1) {
@@ -262,26 +219,23 @@
FileSize = FileInfo.st_size;
}
- // Default is to map the full file.
- if (MapSize == size_t(-1))
- MapSize = FileSize;
-
- if (shouldUseMmap(FileSize, MapSize, Offset, RequiresNullTerminator,
- PageSize)) {
- off_t RealMapOffset = Offset & ~(PageSize - 1);
- off_t Delta = Offset - RealMapOffset;
- size_t RealMapSize = MapSize + Delta;
-
- if (const char *Pages = sys::Path::MapInFilePages(FD,
- RealMapSize,
- RealMapOffset)) {
+
+ // If the file is large, try to use mmap to read it in. We don't use mmap
+ // for small files, because this can severely fragment our address space. Also
+ // don't try to map files that are exactly a multiple of the system page size,
+ // as the file would not have the required null terminator.
+ //
+ // FIXME: Can we just mmap an extra page in the latter case?
+ if (FileSize >= 4096*4 &&
+ (FileSize & (sys::Process::GetPageSize()-1)) != 0) {
+ if (const char *Pages = sys::Path::MapInFilePages(FD, FileSize)) {
result.reset(GetNamedBuffer<MemoryBufferMMapFile>(
- StringRef(Pages + Delta, MapSize), Filename, RequiresNullTerminator));
+ StringRef(Pages, FileSize), Filename));
return success;
}
}
- MemoryBuffer *Buf = MemoryBuffer::getNewUninitMemBuffer(MapSize, Filename);
+ MemoryBuffer *Buf = MemoryBuffer::getNewUninitMemBuffer(FileSize, Filename);
if (!Buf) {
// Failed to create a buffer. The only way it can fail is if
// new(std::nothrow) returns 0.
@@ -291,10 +245,7 @@
OwningPtr<MemoryBuffer> SB(Buf);
char *BufPtr = const_cast<char*>(SB->getBufferStart());
- size_t BytesLeft = MapSize;
- if (lseek(FD, Offset, SEEK_SET) == -1)
- return error_code(errno, posix_category());
-
+ size_t BytesLeft = FileSize;
while (BytesLeft) {
ssize_t NumRead = ::read(FD, BufPtr, BytesLeft);
if (NumRead == -1) {
Modified: llvm/trunk/lib/Support/Unix/Path.inc
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/Unix/Path.inc?rev=127413&r1=127412&r2=127413&view=diff
==============================================================================
--- llvm/trunk/lib/Support/Unix/Path.inc (original)
+++ llvm/trunk/lib/Support/Unix/Path.inc Thu Mar 10 12:01:43 2011
@@ -869,18 +869,18 @@
return false;
}
-const char *Path::MapInFilePages(int FD, size_t FileSize, off_t Offset) {
+const char *Path::MapInFilePages(int FD, uint64_t FileSize) {
int Flags = MAP_PRIVATE;
#ifdef MAP_FILE
Flags |= MAP_FILE;
#endif
- void *BasePtr = ::mmap(0, FileSize, PROT_READ, Flags, FD, Offset);
+ void *BasePtr = ::mmap(0, FileSize, PROT_READ, Flags, FD, 0);
if (BasePtr == MAP_FAILED)
return 0;
return (const char*)BasePtr;
}
-void Path::UnMapFilePages(const char *BasePtr, size_t FileSize) {
+void Path::UnMapFilePages(const char *BasePtr, uint64_t FileSize) {
::munmap((void*)BasePtr, FileSize);
}
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