X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FSupport%2FFormattedStream.cpp;h=618ec2673a1696b899e4fa3ca9138bf9c40ad422;hb=d3198ce4bcc3ec64068d6508f2f08be97e6be83e;hp=1198ebf08e53ad7c8cdbd287cd53b094039c3ba7;hpb=7aaad71722aeb26f14c8523ee55df91e38837a02;p=oota-llvm.git

diff --git a/lib/Support/FormattedStream.cpp b/lib/Support/FormattedStream.cpp
index 1198ebf08e5..618ec2673a1 100644
--- a/lib/Support/FormattedStream.cpp
+++ b/lib/Support/FormattedStream.cpp
@@ -11,57 +11,77 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm/Support/Debug.h"
 #include "llvm/Support/FormattedStream.h"
 #include <algorithm>
 
 using namespace llvm;
 
-/// ComputeColumn - Examine the current output and figure out which
-/// column we end up in after output.
+/// UpdatePosition - Examine the given char sequence and figure out which
+/// column we end up in after output, and how many line breaks are contained.
 ///
-void formatted_raw_ostream::ComputeColumn(unsigned &Column) {
-  // Keep track of the current column by scanning the string for
-  // special characters
+static void UpdatePosition(std::pair<unsigned, unsigned> &Position, const char *Ptr, size_t Size) {
+  unsigned &Column = Position.first;
+  unsigned &Line = Position.second;
 
-  for (const char *Ptr = begin(); Ptr != end(); ++Ptr) {
+  // Keep track of the current column and line by scanning the string for
+  // special characters
+  for (const char *End = Ptr + Size; Ptr != End; ++Ptr) {
     ++Column;
-    if (*Ptr == '\n' || *Ptr == '\r')
+    switch (*Ptr) {
+    case '\n':
+      Line += 1;
+    case '\r':
       Column = 0;
-    else if (*Ptr == '\t')
+      break;
+    case '\t':
+      // Assumes tab stop = 8 characters.
       Column += (8 - (Column & 0x7)) & 0x7;
+      break;
+    }
   }
 }
 
+/// ComputePosition - Examine the current output and update line and column
+/// counts.
+void formatted_raw_ostream::ComputePosition(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.
+    UpdatePosition(Position, Scanned, Size - (Scanned - Ptr));
+  else
+    UpdatePosition(Position, 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) { 
-  // Start out from the last flush position.
-  unsigned Column = ColumnFlushed;
-
-  // Now figure out what's in the buffer and add it to the column
-  // count.
-  ComputeColumn(Column);
+formatted_raw_ostream &formatted_raw_ostream::PadToColumn(unsigned NewCol) { 
+  // Figure out what's in the buffer and add it to the column count.
+  ComputePosition(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 - getColumn()), 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.
+  ComputePosition(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 = nullptr;
 }
 
 /// fouts() - This returns a reference to a formatted_raw_ostream for
@@ -77,3 +97,10 @@ 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;
+}