raw_ostream: Rework implementation of unbuffered streams so outputting
a single character requires only one branch to follow slow path.
- Never use a buffer when writing on an unbuffered stream.
- Move default buffer size to header.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67066 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/raw_ostream.cpp b/lib/Support/raw_ostream.cpp
index 3b33ad6..6aec947 100644
--- a/lib/Support/raw_ostream.cpp
+++ b/lib/Support/raw_ostream.cpp
@@ -123,8 +123,13 @@
}
raw_ostream &raw_ostream::write(unsigned char C) {
+ if (Unbuffered) {
+ write_impl(reinterpret_cast<char*>(&C), 1);
+ return *this;
+ }
+
if (!OutBufStart)
- SetBufferSize(4096);
+ SetBufferSize();
else if (OutBufCur >= OutBufEnd)
flush_nonempty();
@@ -133,8 +138,13 @@
}
raw_ostream &raw_ostream::write(const char *Ptr, unsigned Size) {
+ if (Unbuffered) {
+ write_impl(Ptr, Size);
+ return *this;
+ }
+
if (!OutBufStart)
- SetBufferSize(4096);
+ SetBufferSize();
else if (OutBufCur+Size > OutBufEnd)
flush_nonempty();
@@ -161,8 +171,6 @@
}
OutBufCur += Size;
- if (Unbuffered)
- flush();
return *this;
}