For fastcc on x86, let ECX be used as a return register after EAX and EDX

[oota-llvm.git] / lib / Support / FormattedStream.cpp

diff --git a/lib/Support/FormattedStream.cpp b/lib/Support/FormattedStream.cpp
index 01dea3628c0bcc3827a10129f9753ebb3b345030..70f2cfa6ae882cf0ca772679eaa49b73df9ebc32 100644 (file)
--- a/lib/Support/FormattedStream.cpp
+++ b/lib/Support/FormattedStream.cpp
@@ -7,8 +7,7 @@
 //
 //===----------------------------------------------------------------------===//
 //
-// This file contains the implementation of formatted_raw_ostream and
-// friends.
+// This file contains the implementation of formatted_raw_ostream.
 //
 //===----------------------------------------------------------------------===//
 
@@ -16,21 +15,41 @@
 
 using namespace llvm;
 
-/// ComputeColumn - Examine the current output and figure out which
+/// CountColumns - Examine the given char sequence and figure out which
 /// column we end up in after output.
 ///
-void formatted_raw_ostream::ComputeColumn(const char *Ptr, unsigned Size)
-{
+static unsigned CountColumns(unsigned Column, const char *Ptr, size_t Size) {
   // Keep track of the current column by scanning the string for
   // special characters
 
-  for (const char *epos = Ptr + Size; Ptr != epos; ++Ptr) {
+  for (const char *End = Ptr + Size; Ptr != End; ++Ptr) {
     ++Column;
     if (*Ptr == '\n' || *Ptr == '\r')
       Column = 0;
     else if (*Ptr == '\t')
+      // Assumes tab stop = 8 characters.
       Column += (8 - (Column & 0x7)) & 0x7;
   }
+
+  return Column;
+}
+
+/// ComputeColumn - Examine the current output and figure out which
+/// column we end up in after output.
+void formatted_raw_ostream::ComputeColumn(const char *Ptr, size_t Size) {
+  // If our previous scan pointer is inside the buffer, assume we already
+  // scanned those bytes. This depends on raw_ostream to not change our buffer
+  // in unexpected ways.
+  if (Ptr <= Scanned && Scanned <= Ptr + Size) {
+    // Scan all characters added since our last scan to determine the new
+    // column.
+    ColumnScanned = CountColumns(ColumnScanned, Scanned, 
+                                 Size - (Scanned - Ptr));
+  } else
+    ColumnScanned = CountColumns(ColumnScanned, Ptr, Size);
+
+  // Update the scanning pointer.
+  Scanned = Ptr + Size;
 }
 
 /// PadToColumn - Align the output to some column number.
@@ -39,20 +58,24 @@ void formatted_raw_ostream::ComputeColumn(const char *Ptr, unsigned Size)
 /// \param MinPad - The minimum space to give after the most recent
 /// I/O, even if the current column + minpad > newcol.
 ///
-void formatted_raw_ostream::PadToColumn(unsigned NewCol, unsigned MinPad) 
-{
-  flush();
+void formatted_raw_ostream::PadToColumn(unsigned NewCol) { 
+  // Figure out what's in the buffer and add it to the column count.
+  ComputeColumn(getBufferStart(), GetNumBytesInBuffer());
 
   // Output spaces until we reach the desired column.
-  unsigned num = NewCol - Column;
-  if (NewCol < Column || num < MinPad) {
-    num = MinPad;
-  }
+  indent(std::max(int(NewCol - ColumnScanned), 1));
+}
 
-  // TODO: Write a whole string at a time.
-  while (num-- > 0) {
-    write(' ');
-  }
+void formatted_raw_ostream::write_impl(const char *Ptr, size_t Size) {
+  // Figure out what's in the buffer and add it to the column count.
+  ComputeColumn(Ptr, Size);
+
+  // Write the data to the underlying stream (which is unbuffered, so
+  // the data will be immediately written out).
+  TheStream->write(Ptr, Size);
+
+  // Reset the scanning pointer.
+  Scanned = 0;
 }
 
 /// fouts() - This returns a reference to a formatted_raw_ostream for