vendor/clang/clang-trunk-r154661

1 files changed, 881 insertions, 0 deletions

diff --git a/lib/Frontend/TextDiagnostic.cpp b/lib/Frontend/TextDiagnostic.cpp
new file mode 100644
index 000000000000..9f5dcb483803
--- /dev/null
+++ b/lib/Frontend/TextDiagnostic.cpp
@@ -0,0 +1,881 @@
+//===--- TextDiagnostic.cpp - Text Diagnostic Pretty-Printing -------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Frontend/TextDiagnostic.h"
+#include "clang/Basic/FileManager.h"
+#include "clang/Basic/SourceManager.h"
+#include "clang/Frontend/DiagnosticOptions.h"
+#include "clang/Lex/Lexer.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/ADT/SmallString.h"
+#include <algorithm>
+using namespace clang;
+
+static const enum raw_ostream::Colors noteColor =
+  raw_ostream::BLACK;
+static const enum raw_ostream::Colors fixitColor =
+  raw_ostream::GREEN;
+static const enum raw_ostream::Colors caretColor =
+  raw_ostream::GREEN;
+static const enum raw_ostream::Colors warningColor =
+  raw_ostream::MAGENTA;
+static const enum raw_ostream::Colors errorColor = raw_ostream::RED;
+static const enum raw_ostream::Colors fatalColor = raw_ostream::RED;
+// Used for changing only the bold attribute.
+static const enum raw_ostream::Colors savedColor =
+  raw_ostream::SAVEDCOLOR;
+
+/// \brief Number of spaces to indent when word-wrapping.
+const unsigned WordWrapIndentation = 6;
+
+/// \brief When the source code line we want to print is too long for
+/// the terminal, select the "interesting" region.
+static void selectInterestingSourceRegion(std::string &SourceLine,
+                                          std::string &CaretLine,
+                                          std::string &FixItInsertionLine,
+                                          unsigned EndOfCaretToken,
+                                          unsigned Columns) {
+  unsigned MaxSize = std::max(SourceLine.size(),
+                              std::max(CaretLine.size(), 
+                                       FixItInsertionLine.size()));
+  if (MaxSize > SourceLine.size())
+    SourceLine.resize(MaxSize, ' ');
+  if (MaxSize > CaretLine.size())
+    CaretLine.resize(MaxSize, ' ');
+  if (!FixItInsertionLine.empty() && MaxSize > FixItInsertionLine.size())
+    FixItInsertionLine.resize(MaxSize, ' ');
+    
+  // Find the slice that we need to display the full caret line
+  // correctly.
+  unsigned CaretStart = 0, CaretEnd = CaretLine.size();
+  for (; CaretStart != CaretEnd; ++CaretStart)
+    if (!isspace(CaretLine[CaretStart]))
+      break;
+
+  for (; CaretEnd != CaretStart; --CaretEnd)
+    if (!isspace(CaretLine[CaretEnd - 1]))
+      break;
+
+  // Make sure we don't chop the string shorter than the caret token
+  // itself.
+  if (CaretEnd < EndOfCaretToken)
+    CaretEnd = EndOfCaretToken;
+
+  // If we have a fix-it line, make sure the slice includes all of the
+  // fix-it information.
+  if (!FixItInsertionLine.empty()) {
+    unsigned FixItStart = 0, FixItEnd = FixItInsertionLine.size();
+    for (; FixItStart != FixItEnd; ++FixItStart)
+      if (!isspace(FixItInsertionLine[FixItStart]))
+        break;
+
+    for (; FixItEnd != FixItStart; --FixItEnd)
+      if (!isspace(FixItInsertionLine[FixItEnd - 1]))
+        break;
+
+    if (FixItStart < CaretStart)
+      CaretStart = FixItStart;
+    if (FixItEnd > CaretEnd)
+      CaretEnd = FixItEnd;
+  }
+
+  // CaretLine[CaretStart, CaretEnd) contains all of the interesting
+  // parts of the caret line. While this slice is smaller than the
+  // number of columns we have, try to grow the slice to encompass
+  // more context.
+
+  // If the end of the interesting region comes before we run out of
+  // space in the terminal, start at the beginning of the line.
+  if (Columns > 3 && CaretEnd < Columns - 3)
+    CaretStart = 0;
+
+  unsigned TargetColumns = Columns;
+  if (TargetColumns > 8)
+    TargetColumns -= 8; // Give us extra room for the ellipses.
+  unsigned SourceLength = SourceLine.size();
+  while ((CaretEnd - CaretStart) < TargetColumns) {
+    bool ExpandedRegion = false;
+    // Move the start of the interesting region left until we've
+    // pulled in something else interesting.
+    if (CaretStart == 1)
+      CaretStart = 0;
+    else if (CaretStart > 1) {
+      unsigned NewStart = CaretStart - 1;
+
+      // Skip over any whitespace we see here; we're looking for
+      // another bit of interesting text.
+      while (NewStart && isspace(SourceLine[NewStart]))
+        --NewStart;
+
+      // Skip over this bit of "interesting" text.
+      while (NewStart && !isspace(SourceLine[NewStart]))
+        --NewStart;
+
+      // Move up to the non-whitespace character we just saw.
+      if (NewStart)
+        ++NewStart;
+
+      // If we're still within our limit, update the starting
+      // position within the source/caret line.
+      if (CaretEnd - NewStart <= TargetColumns) {
+        CaretStart = NewStart;
+        ExpandedRegion = true;
+      }
+    }
+
+    // Move the end of the interesting region right until we've
+    // pulled in something else interesting.
+    if (CaretEnd != SourceLength) {
+      assert(CaretEnd < SourceLength && "Unexpected caret position!");
+      unsigned NewEnd = CaretEnd;
+
+      // Skip over any whitespace we see here; we're looking for
+      // another bit of interesting text.
+      while (NewEnd != SourceLength && isspace(SourceLine[NewEnd - 1]))
+        ++NewEnd;
+
+      // Skip over this bit of "interesting" text.
+      while (NewEnd != SourceLength && !isspace(SourceLine[NewEnd - 1]))
+        ++NewEnd;
+
+      if (NewEnd - CaretStart <= TargetColumns) {
+        CaretEnd = NewEnd;
+        ExpandedRegion = true;
+      }
+    }
+
+    if (!ExpandedRegion)
+      break;
+  }
+
+  // [CaretStart, CaretEnd) is the slice we want. Update the various
+  // output lines to show only this slice, with two-space padding
+  // before the lines so that it looks nicer.
+  if (CaretEnd < SourceLine.size())
+    SourceLine.replace(CaretEnd, std::string::npos, "...");
+  if (CaretEnd < CaretLine.size())
+    CaretLine.erase(CaretEnd, std::string::npos);
+  if (FixItInsertionLine.size() > CaretEnd)
+    FixItInsertionLine.erase(CaretEnd, std::string::npos);
+
+  if (CaretStart > 2) {
+    SourceLine.replace(0, CaretStart, "  ...");
+    CaretLine.replace(0, CaretStart, "     ");
+    if (FixItInsertionLine.size() >= CaretStart)
+      FixItInsertionLine.replace(0, CaretStart, "     ");
+  }
+}
+
+/// \brief Skip over whitespace in the string, starting at the given
+/// index.
+///
+/// \returns The index of the first non-whitespace character that is
+/// greater than or equal to Idx or, if no such character exists,
+/// returns the end of the string.
+static unsigned skipWhitespace(unsigned Idx, StringRef Str, unsigned Length) {
+  while (Idx < Length && isspace(Str[Idx]))
+    ++Idx;
+  return Idx;
+}
+
+/// \brief If the given character is the start of some kind of
+/// balanced punctuation (e.g., quotes or parentheses), return the
+/// character that will terminate the punctuation.
+///
+/// \returns The ending punctuation character, if any, or the NULL
+/// character if the input character does not start any punctuation.
+static inline char findMatchingPunctuation(char c) {
+  switch (c) {
+  case '\'': return '\'';
+  case '`': return '\'';
+  case '"':  return '"';
+  case '(':  return ')';
+  case '[': return ']';
+  case '{': return '}';
+  default: break;
+  }
+
+  return 0;
+}
+
+/// \brief Find the end of the word starting at the given offset
+/// within a string.
+///
+/// \returns the index pointing one character past the end of the
+/// word.
+static unsigned findEndOfWord(unsigned Start, StringRef Str,
+                              unsigned Length, unsigned Column,
+                              unsigned Columns) {
+  assert(Start < Str.size() && "Invalid start position!");
+  unsigned End = Start + 1;
+
+  // If we are already at the end of the string, take that as the word.
+  if (End == Str.size())
+    return End;
+
+  // Determine if the start of the string is actually opening
+  // punctuation, e.g., a quote or parentheses.
+  char EndPunct = findMatchingPunctuation(Str[Start]);
+  if (!EndPunct) {
+    // This is a normal word. Just find the first space character.
+    while (End < Length && !isspace(Str[End]))
+      ++End;
+    return End;
+  }
+
+  // We have the start of a balanced punctuation sequence (quotes,
+  // parentheses, etc.). Determine the full sequence is.
+  SmallString<16> PunctuationEndStack;
+  PunctuationEndStack.push_back(EndPunct);
+  while (End < Length && !PunctuationEndStack.empty()) {
+    if (Str[End] == PunctuationEndStack.back())
+      PunctuationEndStack.pop_back();
+    else if (char SubEndPunct = findMatchingPunctuation(Str[End]))
+      PunctuationEndStack.push_back(SubEndPunct);
+
+    ++End;
+  }
+
+  // Find the first space character after the punctuation ended.
+  while (End < Length && !isspace(Str[End]))
+    ++End;
+
+  unsigned PunctWordLength = End - Start;
+  if (// If the word fits on this line
+      Column + PunctWordLength <= Columns ||
+      // ... or the word is "short enough" to take up the next line
+      // without too much ugly white space
+      PunctWordLength < Columns/3)
+    return End; // Take the whole thing as a single "word".
+
+  // The whole quoted/parenthesized string is too long to print as a
+  // single "word". Instead, find the "word" that starts just after
+  // the punctuation and use that end-point instead. This will recurse
+  // until it finds something small enough to consider a word.
+  return findEndOfWord(Start + 1, Str, Length, Column + 1, Columns);
+}
+
+/// \brief Print the given string to a stream, word-wrapping it to
+/// some number of columns in the process.
+///
+/// \param OS the stream to which the word-wrapping string will be
+/// emitted.
+/// \param Str the string to word-wrap and output.
+/// \param Columns the number of columns to word-wrap to.
+/// \param Column the column number at which the first character of \p
+/// Str will be printed. This will be non-zero when part of the first
+/// line has already been printed.
+/// \param Indentation the number of spaces to indent any lines beyond
+/// the first line.
+/// \returns true if word-wrapping was required, or false if the
+/// string fit on the first line.
+static bool printWordWrapped(raw_ostream &OS, StringRef Str,
+                             unsigned Columns,
+                             unsigned Column = 0,
+                             unsigned Indentation = WordWrapIndentation) {
+  const unsigned Length = std::min(Str.find('\n'), Str.size());
+
+  // The string used to indent each line.
+  SmallString<16> IndentStr;
+  IndentStr.assign(Indentation, ' ');
+  bool Wrapped = false;
+  for (unsigned WordStart = 0, WordEnd; WordStart < Length;
+       WordStart = WordEnd) {
+    // Find the beginning of the next word.
+    WordStart = skipWhitespace(WordStart, Str, Length);
+    if (WordStart == Length)
+      break;
+
+    // Find the end of this word.
+    WordEnd = findEndOfWord(WordStart, Str, Length, Column, Columns);
+
+    // Does this word fit on the current line?
+    unsigned WordLength = WordEnd - WordStart;
+    if (Column + WordLength < Columns) {
+      // This word fits on the current line; print it there.
+      if (WordStart) {
+        OS << ' ';
+        Column += 1;
+      }
+      OS << Str.substr(WordStart, WordLength);
+      Column += WordLength;
+      continue;
+    }
+
+    // This word does not fit on the current line, so wrap to the next
+    // line.
+    OS << '\n';
+    OS.write(&IndentStr[0], Indentation);
+    OS << Str.substr(WordStart, WordLength);
+    Column = Indentation + WordLength;
+    Wrapped = true;
+  }
+
+  // Append any remaning text from the message with its existing formatting.
+  OS << Str.substr(Length);
+
+  return Wrapped;
+}
+
+TextDiagnostic::TextDiagnostic(raw_ostream &OS,
+                               const SourceManager &SM,
+                               const LangOptions &LangOpts,
+                               const DiagnosticOptions &DiagOpts)
+  : DiagnosticRenderer(SM, LangOpts, DiagOpts), OS(OS) {}
+
+TextDiagnostic::~TextDiagnostic() {}
+
+void
+TextDiagnostic::emitDiagnosticMessage(SourceLocation Loc,
+                                      PresumedLoc PLoc,
+                                      DiagnosticsEngine::Level Level,
+                                      StringRef Message,
+                                      ArrayRef<clang::CharSourceRange> Ranges,
+                                      DiagOrStoredDiag D) {
+  uint64_t StartOfLocationInfo = OS.tell();
+
+  // Emit the location of this particular diagnostic.
+  emitDiagnosticLoc(Loc, PLoc, Level, Ranges);
+  
+  if (DiagOpts.ShowColors)
+    OS.resetColor();
+  
+  printDiagnosticLevel(OS, Level, DiagOpts.ShowColors);
+  printDiagnosticMessage(OS, Level, Message,
+                         OS.tell() - StartOfLocationInfo,
+                         DiagOpts.MessageLength, DiagOpts.ShowColors);
+}
+
+/*static*/ void
+TextDiagnostic::printDiagnosticLevel(raw_ostream &OS,
+                                     DiagnosticsEngine::Level Level,
+                                     bool ShowColors) {
+  if (ShowColors) {
+    // Print diagnostic category in bold and color
+    switch (Level) {
+    case DiagnosticsEngine::Ignored:
+      llvm_unreachable("Invalid diagnostic type");
+    case DiagnosticsEngine::Note:    OS.changeColor(noteColor, true); break;
+    case DiagnosticsEngine::Warning: OS.changeColor(warningColor, true); break;
+    case DiagnosticsEngine::Error:   OS.changeColor(errorColor, true); break;
+    case DiagnosticsEngine::Fatal:   OS.changeColor(fatalColor, true); break;
+    }
+  }
+
+  switch (Level) {
+  case DiagnosticsEngine::Ignored:
+    llvm_unreachable("Invalid diagnostic type");
+  case DiagnosticsEngine::Note:    OS << "note: "; break;
+  case DiagnosticsEngine::Warning: OS << "warning: "; break;
+  case DiagnosticsEngine::Error:   OS << "error: "; break;
+  case DiagnosticsEngine::Fatal:   OS << "fatal error: "; break;
+  }
+
+  if (ShowColors)
+    OS.resetColor();
+}
+
+/*static*/ void
+TextDiagnostic::printDiagnosticMessage(raw_ostream &OS,
+                                       DiagnosticsEngine::Level Level,
+                                       StringRef Message,
+                                       unsigned CurrentColumn, unsigned Columns,
+                                       bool ShowColors) {
+  if (ShowColors) {
+    // Print warnings, errors and fatal errors in bold, no color
+    switch (Level) {
+    case DiagnosticsEngine::Warning: OS.changeColor(savedColor, true); break;
+    case DiagnosticsEngine::Error:   OS.changeColor(savedColor, true); break;
+    case DiagnosticsEngine::Fatal:   OS.changeColor(savedColor, true); break;
+    default: break; //don't bold notes
+    }
+  }
+
+  if (Columns)
+    printWordWrapped(OS, Message, Columns, CurrentColumn);
+  else
+    OS << Message;
+
+  if (ShowColors)
+    OS.resetColor();
+  OS << '\n';
+}
+
+/// \brief Print out the file/line/column information and include trace.
+///
+/// This method handlen the emission of the diagnostic location information.
+/// This includes extracting as much location information as is present for
+/// the diagnostic and printing it, as well as any include stack or source
+/// ranges necessary.
+void TextDiagnostic::emitDiagnosticLoc(SourceLocation Loc, PresumedLoc PLoc,
+                                       DiagnosticsEngine::Level Level,
+                                       ArrayRef<CharSourceRange> Ranges) {
+  if (PLoc.isInvalid()) {
+    // At least print the file name if available:
+    FileID FID = SM.getFileID(Loc);
+    if (!FID.isInvalid()) {
+      const FileEntry* FE = SM.getFileEntryForID(FID);
+      if (FE && FE->getName()) {
+        OS << FE->getName();
+        if (FE->getDevice() == 0 && FE->getInode() == 0
+            && FE->getFileMode() == 0) {
+          // in PCH is a guess, but a good one:
+          OS << " (in PCH)";
+        }
+        OS << ": ";
+      }
+    }
+    return;
+  }
+  unsigned LineNo = PLoc.getLine();
+
+  if (!DiagOpts.ShowLocation)
+    return;
+
+  if (DiagOpts.ShowColors)
+    OS.changeColor(savedColor, true);
+
+  OS << PLoc.getFilename();
+  switch (DiagOpts.Format) {
+  case DiagnosticOptions::Clang: OS << ':'  << LineNo; break;
+  case DiagnosticOptions::Msvc:  OS << '('  << LineNo; break;
+  case DiagnosticOptions::Vi:    OS << " +" << LineNo; break;
+  }
+
+  if (DiagOpts.ShowColumn)
+    // Compute the column number.
+    if (unsigned ColNo = PLoc.getColumn()) {
+      if (DiagOpts.Format == DiagnosticOptions::Msvc) {
+        OS << ',';
+        ColNo--;
+      } else
+        OS << ':';
+      OS << ColNo;
+    }
+  switch (DiagOpts.Format) {
+  case DiagnosticOptions::Clang:
+  case DiagnosticOptions::Vi:    OS << ':';    break;
+  case DiagnosticOptions::Msvc:  OS << ") : "; break;
+  }
+
+  if (DiagOpts.ShowSourceRanges && !Ranges.empty()) {
+    FileID CaretFileID =
+      SM.getFileID(SM.getExpansionLoc(Loc));
+    bool PrintedRange = false;
+
+    for (ArrayRef<CharSourceRange>::const_iterator RI = Ranges.begin(),
+         RE = Ranges.end();
+         RI != RE; ++RI) {
+      // Ignore invalid ranges.
+      if (!RI->isValid()) continue;
+
+      SourceLocation B = SM.getExpansionLoc(RI->getBegin());
+      SourceLocation E = SM.getExpansionLoc(RI->getEnd());
+
+      // If the End location and the start location are the same and are a
+      // macro location, then the range was something that came from a
+      // macro expansion or _Pragma.  If this is an object-like macro, the
+      // best we can do is to highlight the range.  If this is a
+      // function-like macro, we'd also like to highlight the arguments.
+      if (B == E && RI->getEnd().isMacroID())
+        E = SM.getExpansionRange(RI->getEnd()).second;
+
+      std::pair<FileID, unsigned> BInfo = SM.getDecomposedLoc(B);
+      std::pair<FileID, unsigned> EInfo = SM.getDecomposedLoc(E);
+
+      // If the start or end of the range is in another file, just discard
+      // it.
+      if (BInfo.first != CaretFileID || EInfo.first != CaretFileID)
+        continue;
+
+      // Add in the length of the token, so that we cover multi-char
+      // tokens.
+      unsigned TokSize = 0;
+      if (RI->isTokenRange())
+        TokSize = Lexer::MeasureTokenLength(E, SM, LangOpts);
+
+      OS << '{' << SM.getLineNumber(BInfo.first, BInfo.second) << ':'
+        << SM.getColumnNumber(BInfo.first, BInfo.second) << '-'
+        << SM.getLineNumber(EInfo.first, EInfo.second) << ':'
+        << (SM.getColumnNumber(EInfo.first, EInfo.second)+TokSize)
+        << '}';
+      PrintedRange = true;
+    }
+
+    if (PrintedRange)
+      OS << ':';
+  }
+  OS << ' ';
+}
+
+void TextDiagnostic::emitBasicNote(StringRef Message) {
+  // FIXME: Emit this as a real note diagnostic.
+  // FIXME: Format an actual diagnostic rather than a hard coded string.
+  OS << "note: " << Message << "\n";
+}
+
+void TextDiagnostic::emitIncludeLocation(SourceLocation Loc,
+                                         PresumedLoc PLoc) {
+  if (DiagOpts.ShowLocation)
+    OS << "In file included from " << PLoc.getFilename() << ':'
+       << PLoc.getLine() << ":\n";
+  else
+    OS << "In included file:\n"; 
+}
+
+/// \brief Emit a code snippet and caret line.
+///
+/// This routine emits a single line's code snippet and caret line..
+///
+/// \param Loc The location for the caret.
+/// \param Ranges The underlined ranges for this code snippet.
+/// \param Hints The FixIt hints active for this diagnostic.
+void TextDiagnostic::emitSnippetAndCaret(
+    SourceLocation Loc, DiagnosticsEngine::Level Level,
+    SmallVectorImpl<CharSourceRange>& Ranges,
+    ArrayRef<FixItHint> Hints) {
+  assert(!Loc.isInvalid() && "must have a valid source location here");
+  assert(Loc.isFileID() && "must have a file location here");
+
+  // If caret diagnostics are enabled and we have location, we want to
+  // emit the caret.  However, we only do this if the location moved
+  // from the last diagnostic, if the last diagnostic was a note that
+  // was part of a different warning or error diagnostic, or if the
+  // diagnostic has ranges.  We don't want to emit the same caret
+  // multiple times if one loc has multiple diagnostics.
+  if (!DiagOpts.ShowCarets)
+    return;
+  if (Loc == LastLoc && Ranges.empty() && Hints.empty() &&
+      (LastLevel != DiagnosticsEngine::Note || Level == LastLevel))
+    return;
+
+  // Decompose the location into a FID/Offset pair.
+  std::pair<FileID, unsigned> LocInfo = SM.getDecomposedLoc(Loc);
+  FileID FID = LocInfo.first;
+  unsigned FileOffset = LocInfo.second;
+
+  // Get information about the buffer it points into.
+  bool Invalid = false;
+  const char *BufStart = SM.getBufferData(FID, &Invalid).data();
+  if (Invalid)
+    return;
+
+  unsigned LineNo = SM.getLineNumber(FID, FileOffset);
+  unsigned ColNo = SM.getColumnNumber(FID, FileOffset);
+  unsigned CaretEndColNo
+    = ColNo + Lexer::MeasureTokenLength(Loc, SM, LangOpts);
+
+  // Rewind from the current position to the start of the line.
+  const char *TokPtr = BufStart+FileOffset;
+  const char *LineStart = TokPtr-ColNo+1; // Column # is 1-based.
+
+
+  // Compute the line end.  Scan forward from the error position to the end of
+  // the line.
+  const char *LineEnd = TokPtr;
+  while (*LineEnd != '\n' && *LineEnd != '\r' && *LineEnd != '\0')
+    ++LineEnd;
+
+  // FIXME: This shouldn't be necessary, but the CaretEndColNo can extend past
+  // the source line length as currently being computed. See
+  // test/Misc/message-length.c.
+  CaretEndColNo = std::min(CaretEndColNo, unsigned(LineEnd - LineStart));
+
+  // Copy the line of code into an std::string for ease of manipulation.
+  std::string SourceLine(LineStart, LineEnd);
+
+  // Create a line for the caret that is filled with spaces that is the same
+  // length as the line of source code.
+  std::string CaretLine(LineEnd-LineStart, ' ');
+
+  // Highlight all of the characters covered by Ranges with ~ characters.
+  for (SmallVectorImpl<CharSourceRange>::iterator I = Ranges.begin(),
+                                                  E = Ranges.end();
+       I != E; ++I)
+    highlightRange(*I, LineNo, FID, SourceLine, CaretLine);
+
+  // Next, insert the caret itself.
+  if (ColNo-1 < CaretLine.size())
+    CaretLine[ColNo-1] = '^';
+  else
+    CaretLine.push_back('^');
+
+  expandTabs(SourceLine, CaretLine);
+
+  // If we are in -fdiagnostics-print-source-range-info mode, we are trying
+  // to produce easily machine parsable output.  Add a space before the
+  // source line and the caret to make it trivial to tell the main diagnostic
+  // line from what the user is intended to see.
+  if (DiagOpts.ShowSourceRanges) {
+    SourceLine = ' ' + SourceLine;
+    CaretLine = ' ' + CaretLine;
+  }
+
+  std::string FixItInsertionLine = buildFixItInsertionLine(LineNo,
+                                                           LineStart, LineEnd,
+                                                           Hints);
+
+  // If the source line is too long for our terminal, select only the
+  // "interesting" source region within that line.
+  unsigned Columns = DiagOpts.MessageLength;
+  if (Columns && SourceLine.size() > Columns)
+    selectInterestingSourceRegion(SourceLine, CaretLine, FixItInsertionLine,
+                                  CaretEndColNo, Columns);
+
+  // Finally, remove any blank spaces from the end of CaretLine.
+  while (CaretLine[CaretLine.size()-1] == ' ')
+    CaretLine.erase(CaretLine.end()-1);
+
+  // Emit what we have computed.
+  OS << SourceLine << '\n';
+
+  if (DiagOpts.ShowColors)
+    OS.changeColor(caretColor, true);
+  OS << CaretLine << '\n';
+  if (DiagOpts.ShowColors)
+    OS.resetColor();
+
+  if (!FixItInsertionLine.empty()) {
+    if (DiagOpts.ShowColors)
+      // Print fixit line in color
+      OS.changeColor(fixitColor, false);
+    if (DiagOpts.ShowSourceRanges)
+      OS << ' ';
+    OS << FixItInsertionLine << '\n';
+    if (DiagOpts.ShowColors)
+      OS.resetColor();
+  }
+
+  // Print out any parseable fixit information requested by the options.
+  emitParseableFixits(Hints);
+}
+
+/// \brief Highlight a SourceRange (with ~'s) for any characters on LineNo.
+void TextDiagnostic::highlightRange(const CharSourceRange &R,
+                                    unsigned LineNo, FileID FID,
+                                    const std::string &SourceLine,
+                                    std::string &CaretLine) {
+  assert(CaretLine.size() == SourceLine.size() &&
+         "Expect a correspondence between source and caret line!");
+  if (!R.isValid()) return;
+
+  SourceLocation Begin = SM.getExpansionLoc(R.getBegin());
+  SourceLocation End = SM.getExpansionLoc(R.getEnd());
+
+  // If the End location and the start location are the same and are a macro
+  // location, then the range was something that came from a macro expansion
+  // or _Pragma.  If this is an object-like macro, the best we can do is to
+  // highlight the range.  If this is a function-like macro, we'd also like to
+  // highlight the arguments.
+  if (Begin == End && R.getEnd().isMacroID())
+    End = SM.getExpansionRange(R.getEnd()).second;
+
+  unsigned StartLineNo = SM.getExpansionLineNumber(Begin);
+  if (StartLineNo > LineNo || SM.getFileID(Begin) != FID)
+    return;  // No intersection.
+
+  unsigned EndLineNo = SM.getExpansionLineNumber(End);
+  if (EndLineNo < LineNo || SM.getFileID(End) != FID)
+    return;  // No intersection.
+
+  // Compute the column number of the start.
+  unsigned StartColNo = 0;
+  if (StartLineNo == LineNo) {
+    StartColNo = SM.getExpansionColumnNumber(Begin);
+    if (StartColNo) --StartColNo;  // Zero base the col #.
+  }
+
+  // Compute the column number of the end.
+  unsigned EndColNo = CaretLine.size();
+  if (EndLineNo == LineNo) {
+    EndColNo = SM.getExpansionColumnNumber(End);
+    if (EndColNo) {
+      --EndColNo;  // Zero base the col #.
+
+      // Add in the length of the token, so that we cover multi-char tokens if
+      // this is a token range.
+      if (R.isTokenRange())
+        EndColNo += Lexer::MeasureTokenLength(End, SM, LangOpts);
+    } else {
+      EndColNo = CaretLine.size();
+    }
+  }
+
+  assert(StartColNo <= EndColNo && "Invalid range!");
+
+  // Check that a token range does not highlight only whitespace.
+  if (R.isTokenRange()) {
+    // Pick the first non-whitespace column.
+    while (StartColNo < SourceLine.size() &&
+           (SourceLine[StartColNo] == ' ' || SourceLine[StartColNo] == '\t'))
+      ++StartColNo;
+
+    // Pick the last non-whitespace column.
+    if (EndColNo > SourceLine.size())
+      EndColNo = SourceLine.size();
+    while (EndColNo-1 &&
+           (SourceLine[EndColNo-1] == ' ' || SourceLine[EndColNo-1] == '\t'))
+      --EndColNo;
+
+    // If the start/end passed each other, then we are trying to highlight a
+    // range that just exists in whitespace, which must be some sort of other
+    // bug.
+    assert(StartColNo <= EndColNo && "Trying to highlight whitespace??");
+  }
+
+  // Fill the range with ~'s.
+  for (unsigned i = StartColNo; i < EndColNo; ++i)
+    CaretLine[i] = '~';
+}
+
+std::string TextDiagnostic::buildFixItInsertionLine(unsigned LineNo,
+                                                    const char *LineStart,
+                                                    const char *LineEnd,
+                                                    ArrayRef<FixItHint> Hints) {
+  std::string FixItInsertionLine;
+  if (Hints.empty() || !DiagOpts.ShowFixits)
+    return FixItInsertionLine;
+
+  for (ArrayRef<FixItHint>::iterator I = Hints.begin(), E = Hints.end();
+       I != E; ++I) {
+    if (!I->CodeToInsert.empty()) {
+      // We have an insertion hint. Determine whether the inserted
+      // code is on the same line as the caret.
+      std::pair<FileID, unsigned> HintLocInfo
+        = SM.getDecomposedExpansionLoc(I->RemoveRange.getBegin());
+      if (LineNo == SM.getLineNumber(HintLocInfo.first, HintLocInfo.second)) {
+        // Insert the new code into the line just below the code
+        // that the user wrote.
+        unsigned HintColNo
+          = SM.getColumnNumber(HintLocInfo.first, HintLocInfo.second);
+        unsigned LastColumnModified
+          = HintColNo - 1 + I->CodeToInsert.size();
+        if (LastColumnModified > FixItInsertionLine.size())
+          FixItInsertionLine.resize(LastColumnModified, ' ');
+        std::copy(I->CodeToInsert.begin(), I->CodeToInsert.end(),
+                  FixItInsertionLine.begin() + HintColNo - 1);
+      } else {
+        FixItInsertionLine.clear();
+        break;
+      }
+    }
+  }
+
+  if (FixItInsertionLine.empty())
+    return FixItInsertionLine;
+
+  // Now that we have the entire fixit line, expand the tabs in it.
+  // Since we don't want to insert spaces in the middle of a word,
+  // find each word and the column it should line up with and insert
+  // spaces until they match.
+  unsigned FixItPos = 0;
+  unsigned LinePos = 0;
+  unsigned TabExpandedCol = 0;
+  unsigned LineLength = LineEnd - LineStart;
+
+  while (FixItPos < FixItInsertionLine.size() && LinePos < LineLength) {
+    // Find the next word in the FixIt line.
+    while (FixItPos < FixItInsertionLine.size() &&
+           FixItInsertionLine[FixItPos] == ' ')
+      ++FixItPos;
+    unsigned CharDistance = FixItPos - TabExpandedCol;
+
+    // Walk forward in the source line, keeping track of
+    // the tab-expanded column.
+    for (unsigned I = 0; I < CharDistance; ++I, ++LinePos)
+      if (LinePos >= LineLength || LineStart[LinePos] != '\t')
+        ++TabExpandedCol;
+      else
+        TabExpandedCol =
+          (TabExpandedCol/DiagOpts.TabStop + 1) * DiagOpts.TabStop;
+
+    // Adjust the fixit line to match this column.
+    FixItInsertionLine.insert(FixItPos, TabExpandedCol-FixItPos, ' ');
+    FixItPos = TabExpandedCol;
+
+    // Walk to the end of the word.
+    while (FixItPos < FixItInsertionLine.size() &&
+           FixItInsertionLine[FixItPos] != ' ')
+      ++FixItPos;
+  }
+
+  return FixItInsertionLine;
+}
+
+void TextDiagnostic::expandTabs(std::string &SourceLine,
+                                std::string &CaretLine) {
+  // Scan the source line, looking for tabs.  If we find any, manually expand
+  // them to spaces and update the CaretLine to match.
+  for (unsigned i = 0; i != SourceLine.size(); ++i) {
+    if (SourceLine[i] != '\t') continue;
+
+    // Replace this tab with at least one space.
+    SourceLine[i] = ' ';
+
+    // Compute the number of spaces we need to insert.
+    unsigned TabStop = DiagOpts.TabStop;
+    assert(0 < TabStop && TabStop <= DiagnosticOptions::MaxTabStop &&
+           "Invalid -ftabstop value");
+    unsigned NumSpaces = ((i+TabStop)/TabStop * TabStop) - (i+1);
+    assert(NumSpaces < TabStop && "Invalid computation of space amt");
+
+    // Insert spaces into the SourceLine.
+    SourceLine.insert(i+1, NumSpaces, ' ');
+
+    // Insert spaces or ~'s into CaretLine.
+    CaretLine.insert(i+1, NumSpaces, CaretLine[i] == '~' ? '~' : ' ');
+  }
+}
+
+void TextDiagnostic::emitParseableFixits(ArrayRef<FixItHint> Hints) {
+  if (!DiagOpts.ShowParseableFixits)
+    return;
+
+  // We follow FixItRewriter's example in not (yet) handling
+  // fix-its in macros.
+  for (ArrayRef<FixItHint>::iterator I = Hints.begin(), E = Hints.end();
+       I != E; ++I) {
+    if (I->RemoveRange.isInvalid() ||
+        I->RemoveRange.getBegin().isMacroID() ||
+        I->RemoveRange.getEnd().isMacroID())
+      return;
+  }
+
+  for (ArrayRef<FixItHint>::iterator I = Hints.begin(), E = Hints.end();
+       I != E; ++I) {
+    SourceLocation BLoc = I->RemoveRange.getBegin();
+    SourceLocation ELoc = I->RemoveRange.getEnd();
+
+    std::pair<FileID, unsigned> BInfo = SM.getDecomposedLoc(BLoc);
+    std::pair<FileID, unsigned> EInfo = SM.getDecomposedLoc(ELoc);
+
+    // Adjust for token ranges.
+    if (I->RemoveRange.isTokenRange())
+      EInfo.second += Lexer::MeasureTokenLength(ELoc, SM, LangOpts);
+
+    // We specifically do not do word-wrapping or tab-expansion here,
+    // because this is supposed to be easy to parse.
+    PresumedLoc PLoc = SM.getPresumedLoc(BLoc);
+    if (PLoc.isInvalid())
+      break;
+
+    OS << "fix-it:\"";
+    OS.write_escaped(PLoc.getFilename());
+    OS << "\":{" << SM.getLineNumber(BInfo.first, BInfo.second)
+      << ':' << SM.getColumnNumber(BInfo.first, BInfo.second)
+      << '-' << SM.getLineNumber(EInfo.first, EInfo.second)
+      << ':' << SM.getColumnNumber(EInfo.first, EInfo.second)
+      << "}:\"";
+    OS.write_escaped(I->CodeToInsert);
+    OS << "\"\n";
+  }
+}
+