am 31675153: Merge branch \'upstream\' into merge_2

* commit '31675153bd2d7617db8cb6aeb58054934c7b9f73': (542 commits)
  MaximumSpanningTree::EdgeWeightCompare: Make this comparator actually be a strict weak ordering, and don't pass possibly-null pointers to dyn_cast.
  Fix misaligned access in MachO object file reader: despite containing an int64_t, Symbol64TableEntry is actually only stored with 4-byte alignment within the file.
  Fix unaligned memory accesses when performing relocations in X86 JIT. There's no cost to using memcpy here: the fixed code is optimized by LLVM to perfect machine code.
  Don't pass a null pointer to cast<> in its unit tests.
  Don't bind a reference to a dereferenced null pointer (for return value of WeakVH::operator*).
  [ms-inline asm] Do not report a Parser error when matching inline assembly.
  Ignore the documentation-suggested location for compile_commands.json
  The presence of the empty file "foo" unfortunately does not improve LLVM in any way.
  Remove unnecessary cast that was also unnecessarily casting away constness.
  Provide a portability macro for __builtin_trap.
  Fix macros arguments with an underscore, dot or dollar in them. This is based on a patch by Andy/PaX. I added the support for dot and dollar.
  [ms-inline asm] Expose the ErrorInfo from the MatchInstructionImpl.  In general, this is the index of the operand that failed to match.
  Formatting.  No functional change.
  Make the wording in of the "expected identifier" error in the .macro directive consistent with the other "expected identifier" errors. Extracted from the Andy/PaX patch. I added the test.
  Pacify PVS-Studio by changing the type rather than doing a cast, a tweak suggested by David Blaikie.
  Add support for the --param ssp-buffer-size= driver option. PR9673
  Use typedefs. Fix indentation. Extracted from the Andy/PaX patch.
  Remove unused variable. Extracted from the Andy/PaX patch.
  Fix typo. Extracted from the Andy/PaX patch.
  MCJIT: Tidy up the constructor.
  ...

1 files changed, 97 insertions, 0 deletions

diff --git a/include/llvm/Support/FileOutputBuffer.h b/include/llvm/Support/FileOutputBuffer.h
new file mode 100644
index 0000000..0f07164
--- /dev/null
+++ b/include/llvm/Support/FileOutputBuffer.h
@@ -0,0 +1,97 @@
+//=== FileOutputBuffer.h - File Output Buffer -------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Utility for creating a in-memory buffer that will be written to a file.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SUPPORT_FILEOUTPUTBUFFER_H
+#define LLVM_SUPPORT_FILEOUTPUTBUFFER_H
+
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/DataTypes.h"
+
+namespace llvm {
+
+class error_code;
+template<class T> class OwningPtr;
+
+/// FileOutputBuffer - This interface provides simple way to create an in-memory
+/// buffer which will be written to a file. During the lifetime of these 
+/// objects, the content or existence of the specified file is undefined. That
+/// is, creating an OutputBuffer for a file may immediately remove the file.
+/// If the FileOutputBuffer is committed, the target file's content will become 
+/// the buffer content at the time of the commit.  If the FileOutputBuffer is  
+/// not committed, the file will be deleted in the FileOutputBuffer destructor.
+class FileOutputBuffer {
+public:
+
+  enum  {
+    F_executable = 1  /// set the 'x' bit on the resulting file
+  }; 
+
+  /// Factory method to create an OutputBuffer object which manages a read/write
+  /// buffer of the specified size. When committed, the buffer will be written
+  /// to the file at the specified path.  
+  static error_code create(StringRef FilePath, size_t Size, 
+                           OwningPtr<FileOutputBuffer> &Result, 
+                           unsigned Flags=0);
+  
+
+  /// Returns a pointer to the start of the buffer.
+  uint8_t *getBufferStart() const {
+    return BufferStart;
+  }
+  
+  /// Returns a pointer to the end of the buffer.
+  uint8_t *getBufferEnd() const {
+    return BufferEnd;
+  }
+  
+  /// Returns size of the buffer.
+  size_t getBufferSize() const {
+    return BufferEnd - BufferStart;
+  }
+  
+  /// Returns path where file will show up if buffer is committed.
+  StringRef getPath() const {
+    return FinalPath;
+  }
+    
+  /// Flushes the content of the buffer to its file and deallocates the 
+  /// buffer.  If commit() is not called before this object's destructor
+  /// is called, the file is deleted in the destructor. The optional parameter
+  /// is used if it turns out you want the file size to be smaller than
+  /// initially requested.
+  error_code commit(int64_t NewSmallerSize = -1);
+  
+  /// If this object was previously committed, the destructor just deletes
+  /// this object.  If this object was not committed, the destructor
+  /// deallocates the buffer and the target file is never written.
+  ~FileOutputBuffer();
+
+  
+protected:
+  FileOutputBuffer(const FileOutputBuffer &); // DO NOT IMPLEMENT
+  FileOutputBuffer &operator=(const FileOutputBuffer &); // DO NOT IMPLEMENT
+  FileOutputBuffer(uint8_t *Start, uint8_t *End, 
+                    StringRef Path, StringRef TempPath);
+    
+  uint8_t            *BufferStart;
+  uint8_t            *BufferEnd;
+  SmallString<128>    FinalPath;
+  SmallString<128>    TempPath;
+};
+
+
+
+} // end namespace llvm
+
+#endif