Make backtraces work again with both the configure and cmake build.

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

diff --git a/lib/Support/FormattedStream.cpp b/lib/Support/FormattedStream.cpp
index 0db21f651a7e4062ace49af81ae9ee6aec6db11d..231ae48759e27fc4de07c10f38a442cba819819f 100644 (file)
--- a/lib/Support/FormattedStream.cpp
+++ b/lib/Support/FormattedStream.cpp
@@ -11,7 +11,9 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm/Support/Debug.h"
 #include "llvm/Support/FormattedStream.h"
+#include <algorithm>
 
 using namespace llvm;
 
@@ -36,59 +38,45 @@ static unsigned CountColumns(unsigned Column, const char *Ptr, size_t Size) {
 
 /// ComputeColumn - Examine the current output and figure out which
 /// column we end up in after output.
-void formatted_raw_ostream::ComputeColumn() {
-  // The buffer may have been allocated underneath us.
-  if (Scanned == 0) Scanned = begin();
-  // Scan all characters added since our last scan to determine the new column.
-  ColumnScanned = CountColumns(ColumnScanned, Scanned, end() - Scanned);
-  // We're now current with everything in the buffer.
-  Scanned = end();
+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) { 
+formatted_raw_ostream &formatted_raw_ostream::PadToColumn(unsigned NewCol) { 
   // Figure out what's in the buffer and add it to the column count.
-  ComputeColumn();
+  ComputeColumn(getBufferStart(), GetNumBytesInBuffer());
 
   // Output spaces until we reach the desired column.
-  unsigned num = NewCol - ColumnScanned;
-  if (NewCol < ColumnScanned || num < MinPad)
-    num = MinPad;
-
-  // Keep a buffer of spaces handy to speed up processing.
-  const char *Spaces = "                                                      "
-    "                                                                         ";
-
-  assert(num < MAX_COLUMN_PAD && "Unexpectedly large column padding");
-
-  write(Spaces, num);
+  indent(std::max(int(NewCol - ColumnScanned), 1));
+  return *this;
 }
 
 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();
+  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);
 
-  // If this FormattedStream is unbuffered, scan the string that
-  // was just written to determine the new column.
-  if (Ptr == begin()) {
-    // Buffered mode. The buffer is being flushed; reset the scanning
-    // position to the beginning of the buffer.
-    assert(Ptr + Size == end() && "Buffer is not being fully flushed!");
-    Scanned = begin();
-  } else {
-    // Unbuffered mode. Immediately scan the string that was just
-    // written to determine the new column.
-    ColumnScanned = CountColumns(ColumnScanned, Ptr, Size);
-  }
+  // Reset the scanning pointer.
+  Scanned = 0;
 }
 
 /// fouts() - This returns a reference to a formatted_raw_ostream for
@@ -104,3 +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;
+}