Improve raw_ostream so that you can "write" colors using operator<<

1. raw_ostream supports ANSI colors so that you can write messages to
the termina with colors. Previously, in order to change and reset
color, you had to call `changeColor` and `resetColor` functions,
respectively.

So, if you print out "error: " in red, for example, you had to do
something like this:

  OS.changeColor(raw_ostream::RED);
  OS << "error: ";
  OS.resetColor();

With this patch, you can write the same code as follows:

  OS << raw_ostream::RED << "error: " << raw_ostream::RESET;

2. Add a boolean flag to raw_ostream so that you can disable colored
output. If you disable colors, changeColor, operator<<(Color),
resetColor and other color-related functions have no effect.

Most LLVM tools automatically prints out messages using colors, and
you can disable it by passing a flag such as `--disable-colors`.
This new flag makes it easy to write code that works that way.

Differential Revision: https://reviews.llvm.org/D65564

llvm-svn: 367649

6 files changed, 11 insertions, 14 deletions

diff --git a/llvm/tools/llvm-cov/CoverageReport.cpp b/llvm/tools/llvm-cov/CoverageReport.cpp
index 82259542c59..1750d18d4e0 100644
--- a/llvm/tools/llvm-cov/CoverageReport.cpp
+++ b/llvm/tools/llvm-cov/CoverageReport.cpp
@@ -111,7 +111,7 @@ void renderDivider(ArrayRef<size_t> ColumnWidths, raw_ostream &OS) {
 /// Return the color which correponds to the coverage percentage of a
 /// certain metric.
 template <typename T>
-raw_ostream::Colors determineCoveragePercentageColor(const T &Info) {
+raw_ostream::Color determineCoveragePercentageColor(const T &Info) {
   if (Info.isFullyCovered())
     return raw_ostream::GREEN;
   return Info.getPercentCovered() >= 80.0 ? raw_ostream::YELLOW
diff --git a/llvm/tools/llvm-cov/CoverageViewOptions.h b/llvm/tools/llvm-cov/CoverageViewOptions.h
index dde0c692ab0..3dbb0131ddb 100644
--- a/llvm/tools/llvm-cov/CoverageViewOptions.h
+++ b/llvm/tools/llvm-cov/CoverageViewOptions.h
@@ -46,7 +46,7 @@ struct CoverageViewOptions {
 
   /// Change the output's stream color if the colors are enabled.
   ColoredRawOstream colored_ostream(raw_ostream &OS,
-                                    raw_ostream::Colors Color) const {
+                                    raw_ostream::Color Color) const {
     return llvm::colored_ostream(OS, Color, Colors);
   }
 
diff --git a/llvm/tools/llvm-cov/RenderingSupport.h b/llvm/tools/llvm-cov/RenderingSupport.h
index 0674fbac9a3..b25792e2c4b 100644
--- a/llvm/tools/llvm-cov/RenderingSupport.h
+++ b/llvm/tools/llvm-cov/RenderingSupport.h
@@ -47,7 +47,7 @@ inline raw_ostream &operator<<(const ColoredRawOstream &OS, T &&Value) {
 /// Change the color of the output stream if the `IsColorUsed` flag
 /// is true. Returns an object that resets the color when destroyed.
 inline ColoredRawOstream colored_ostream(raw_ostream &OS,
-                                         raw_ostream::Colors Color,
+                                         raw_ostream::Color Color,
                                          bool IsColorUsed = true,
                                          bool Bold = false, bool BG = false) {
   if (IsColorUsed)
diff --git a/llvm/tools/llvm-cov/SourceCoverageViewText.cpp b/llvm/tools/llvm-cov/SourceCoverageViewText.cpp
index fcabee2ee69..f73b91a8511 100644
--- a/llvm/tools/llvm-cov/SourceCoverageViewText.cpp
+++ b/llvm/tools/llvm-cov/SourceCoverageViewText.cpp
@@ -101,7 +101,7 @@ void SourceCoverageViewText::renderLine(raw_ostream &OS, LineRef L,
   auto *WrappedSegment = LCS.getWrappedSegment();
   CoverageSegmentArray Segments = LCS.getLineSegments();
 
-  Optional<raw_ostream::Colors> Highlight;
+  Optional<raw_ostream::Color> Highlight;
   SmallVector<std::pair<unsigned, unsigned>, 2> HighlightedRanges;
 
   // The first segment overlaps from a previous line, so we treat it specially.
diff --git a/llvm/tools/llvm-cov/llvm-cov.cpp b/llvm/tools/llvm-cov/llvm-cov.cpp
index 172ec9f3ced..dabb8afedc8 100644
--- a/llvm/tools/llvm-cov/llvm-cov.cpp
+++ b/llvm/tools/llvm-cov/llvm-cov.cpp
@@ -83,13 +83,10 @@ int main(int argc, const char **argv) {
     }
   }
 
-  if (argc > 1) {
-    if (sys::Process::StandardErrHasColors())
-      errs().changeColor(raw_ostream::RED);
-    errs() << "Unrecognized command: " << argv[1] << ".\n\n";
-    if (sys::Process::StandardErrHasColors())
-      errs().resetColor();
-  }
+  if (argc > 1)
+    errs() << raw_ostream::RED << "Unrecognized command: " << argv[1] << ".\n\n"
+           << raw_ostream::RESET;
+
   helpMain(argc, argv);
   return 1;
 }
diff --git a/llvm/tools/llvm-mca/Views/TimelineView.cpp b/llvm/tools/llvm-mca/Views/TimelineView.cpp
index fe3f16ba344..09b6b2a3efe 100644
--- a/llvm/tools/llvm-mca/Views/TimelineView.cpp
+++ b/llvm/tools/llvm-mca/Views/TimelineView.cpp
@@ -103,8 +103,8 @@ void TimelineView::onEvent(const HWInstructionEvent &Event) {
     LastCycle = std::max(LastCycle, CurrentCycle);
 }
 
-static raw_ostream::Colors chooseColor(unsigned CumulativeCycles,
-                                       unsigned Executions, int BufferSize) {
+static raw_ostream::Color chooseColor(unsigned CumulativeCycles,
+                                      unsigned Executions, int BufferSize) {
   if (CumulativeCycles && BufferSize < 0)
     return raw_ostream::MAGENTA;
   unsigned Size = static_cast<unsigned>(BufferSize);
@@ -120,7 +120,7 @@ static void tryChangeColor(raw_ostream &OS, unsigned Cycles,
   if (!OS.has_colors())
     return;
 
-  raw_ostream::Colors Color = chooseColor(Cycles, Executions, BufferSize);
+  raw_ostream::Color Color = chooseColor(Cycles, Executions, BufferSize);
   if (Color == raw_ostream::SAVEDCOLOR) {
     OS.resetColor();
     return;