Drop an unnecessary use of writev.

[oota-llvm.git] / include / llvm / Support / raw_ostream.h

diff --git a/include/llvm/Support/raw_ostream.h b/include/llvm/Support/raw_ostream.h
index 75857a2027af752e5ace4a808b92b5dc89b5a795..d1e96f892a4b43f548c40f6db816a07d0b9545c6 100644 (file)
--- a/include/llvm/Support/raw_ostream.h
+++ b/include/llvm/Support/raw_ostream.h
@@ -218,10 +218,10 @@ public:
 
   // Formatted output, see the leftJustify() function in Support/Format.h.
   raw_ostream &operator<<(const FormattedString &);
-  
+
   // Formatted output, see the formatHex() function in Support/Format.h.
   raw_ostream &operator<<(const FormattedNumber &);
-  
+
   /// indent - Insert 'NumSpaces' spaces.
   raw_ostream &indent(unsigned NumSpaces);
 
@@ -349,10 +349,6 @@ class raw_fd_ostream : public raw_pwrite_stream {
   ///
   bool Error;
 
-  /// Controls whether the stream should attempt to use atomic writes, when
-  /// possible.
-  bool UseAtomicWrites;
-
   uint64_t pos;
 
   bool SupportsSeeking;
@@ -402,16 +398,6 @@ public:
   /// to the offset specified from the beginning of the file.
   uint64_t seek(uint64_t off);
 
-  /// Set the stream to attempt to use atomic writes for individual output
-  /// routines where possible.
-  ///
-  /// Note that because raw_ostream's are typically buffered, this flag is only
-  /// sensible when used on unbuffered streams which will flush their output
-  /// immediately.
-  void SetUseAtomicWrites(bool Value) {
-    UseAtomicWrites = Value;
-  }
-
   raw_ostream &changeColor(enum Colors colors, bool bold=false,
                            bool bg=false) override;
   raw_ostream &resetColor() override;
@@ -485,6 +471,9 @@ public:
 
 /// A raw_ostream that writes to an SmallVector or SmallString.  This is a
 /// simple adaptor class. This class does not encounter output errors.
+/// raw_svector_ostream operates without a buffer, delegating all memory
+/// management to the SmallString. Thus the SmallString is always up-to-date,
+/// may be used directly and there is no need to call flush().
 class raw_svector_ostream : public raw_pwrite_stream {
   SmallVectorImpl<char> &OS;
 
@@ -493,31 +482,23 @@ class raw_svector_ostream : public raw_pwrite_stream {
 
   void pwrite_impl(const char *Ptr, size_t Size, uint64_t Offset) override;
 
-  /// Return the current position within the stream, not counting the bytes
-  /// currently in the buffer.
+  /// Return the current position within the stream.
   uint64_t current_pos() const override;
 
-protected:
-  // Like the regular constructor, but doesn't call init.
-  explicit raw_svector_ostream(SmallVectorImpl<char> &O, unsigned);
-  void init();
-
 public:
   /// Construct a new raw_svector_ostream.
   ///
   /// \param O The vector to write to; this should generally have at least 128
   /// bytes free to avoid any extraneous memory overhead.
-  explicit raw_svector_ostream(SmallVectorImpl<char> &O);
-  ~raw_svector_ostream() override;
+  explicit raw_svector_ostream(SmallVectorImpl<char> &O) : OS(O) {
+    SetUnbuffered();
+  }
+  ~raw_svector_ostream() override {}
 
-  /// This is called when the SmallVector we're appending to is changed outside
-  /// of the raw_svector_ostream's control.  It is only safe to do this if the
-  /// raw_svector_ostream has previously been flushed.
-  void resync();
+  void flush() = delete;
 
-  /// Flushes the stream contents to the target vector and return a StringRef
-  /// for the vector contents.
-  StringRef str();
+  /// Return a StringRef for the vector contents.
+  StringRef str() { return StringRef(OS.data(), OS.size()); }
 };
 
 /// A raw_ostream that discards all output.
@@ -540,12 +521,10 @@ class buffer_ostream : public raw_svector_ostream {
   SmallVector<char, 0> Buffer;
 
 public:
-  buffer_ostream(raw_ostream &OS) : raw_svector_ostream(Buffer, 0), OS(OS) {
-    init();
-  }
-  ~buffer_ostream() { OS << str(); }
+  buffer_ostream(raw_ostream &OS) : raw_svector_ostream(Buffer), OS(OS) {}
+  ~buffer_ostream() override { OS << str(); }
 };
 
 } // end llvm namespace
 
-#endif
+#endif // LLVM_SUPPORT_RAW_OSTREAM_H