X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FSupport%2FFormattedStream.cpp;h=231ae48759e27fc4de07c10f38a442cba819819f;hb=a9498a2ee63f11ca925497199b96abcefdd70582;hp=1796f9f956888d32088e26d5ebd50c42a4b3eddb;hpb=95db93caa1130725123eb50479d0c51c09e8a2f4;p=oota-llvm.git

diff --git a/lib/Support/FormattedStream.cpp b/lib/Support/FormattedStream.cpp
index 1796f9f9568..231ae48759e 100644
--- a/lib/Support/FormattedStream.cpp
+++ b/lib/Support/FormattedStream.cpp
@@ -11,52 +11,72 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm/Support/Debug.h"
 #include "llvm/Support/FormattedStream.h"
 #include <algorithm>
 
 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, size_t 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.
 ///
 /// \param NewCol - The column to move to.
-/// \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();
+formatted_raw_ostream &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));
+  return *this;
+}
 
-  // Keep a buffer of spaces handy to speed up processing.
-  static char Spaces[MAX_COLUMN_PAD];
-  static bool Initialized = false;
-  if (!Initialized) {
-    std::fill_n(Spaces, MAX_COLUMN_PAD, ' '),
-    Initialized = true;
-  }
+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);
 
-  assert(num < MAX_COLUMN_PAD && "Unexpectedly large column padding");
+  // Write the data to the underlying stream (which is unbuffered, so
+  // the data will be immediately written out).
+  TheStream->write(Ptr, Size);
 
-  write(Spaces, num);
+  // Reset the scanning pointer.
+  Scanned = 0;
 }
 
 /// fouts() - This returns a reference to a formatted_raw_ostream for
@@ -72,3 +92,10 @@ formatted_raw_ostream &llvm::ferrs() {
   static formatted_raw_ostream S(errs());
   return S;
 }
+
+/// fdbgs() - This returns a reference to a formatted_raw_ostream for
+/// the debug stream.  Use it like: fdbgs() << "foo" << "bar";
+formatted_raw_ostream &llvm::fdbgs() {
+  static formatted_raw_ostream S(dbgs());
+  return S;
+}