[llvm-profdata] Add SaturatingAdd/SaturatingMultiply Helper Functions

[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 b59317112c4400616787588b305ab2daba8b1c2a..e5cc40e7d6b22d99790b572b0302378150b99abf 100644 (file)
--- a/include/llvm/Support/raw_ostream.h
+++ b/include/llvm/Support/raw_ostream.h
@@ -165,8 +165,10 @@ public:
     if (Size > (size_t)(OutBufEnd - OutBufCur))
       return write(Str.data(), Size);
 
-    memcpy(OutBufCur, Str.data(), Size);
-    OutBufCur += Size;
+    if (Size) {
+      memcpy(OutBufCur, Str.data(), Size);
+      OutBufCur += Size;
+    }
     return *this;
   }
 
@@ -216,14 +218,13 @@ 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);
 
-
   /// Changes the foreground color of text that will be output from this point
   /// forward.
   /// @param Color ANSI color to use, the special SAVEDCOLOR can be used to
@@ -244,7 +245,7 @@ public:
   /// outputting colored text, or before program exit.
   virtual raw_ostream &resetColor() { return *this; }
 
-  /// Reverses the forground and background colors.
+  /// Reverses the foreground and background colors.
   virtual raw_ostream &reverseColor() { return *this; }
 
   /// This function determines if this stream is connected to a "tty" or
@@ -314,7 +315,7 @@ private:
 };
 
 /// An abstract base class for streams implementations that also support a
-/// pwrite operation. This is usefull for code that can mostly stream out data,
+/// pwrite operation. This is useful for code that can mostly stream out data,
 /// but needs to patch in a header that needs to know the output size.
 class raw_pwrite_stream : public raw_ostream {
   virtual void pwrite_impl(const char *Ptr, size_t Size, uint64_t Offset) = 0;
@@ -469,6 +470,7 @@ class raw_string_ostream : public raw_ostream {
   /// Return the current position within the stream, not counting the bytes
   /// currently in the buffer.
   uint64_t current_pos() const override { return OS.size(); }
+
 public:
   explicit raw_string_ostream(std::string &O) : OS(O) {}
   ~raw_string_ostream() override;
@@ -483,6 +485,9 @@ 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;
 
@@ -491,32 +496,23 @@ 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.
@@ -539,12 +535,10 @@ 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