Add support for optimization reports.

Summary:
This patch adds a new flag -Rpass=. The flag indicates the name
of the optimization pass that should emit remarks stating when it
made a transformation to the code.

This implements the design I proposed in:

https://docs.google.com/document/d/1FYUatSjZZO-zmFBxjOiuOzAy9mhHA8hqdvklZv68WuQ/edit?usp=sharing

Other changes:
- Add DiagnosticIDs::isRemark(). Use it in printDiagnosticOptions to
  print "-R" instead of "-W" in the diagnostic message.

- In BackendConsumer::OptimizationRemarkHandler, get a SourceLocation
  object out of the file name, line and column number. Use that location
  in the call to Diags.Report().

- When -Rpass is used without debug info a note is emitted alerting
  the user that they need to use -gline-tables-only -gcolumn-info to
  get this information.

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D3226

llvm-svn: 206401

1 files changed, 3 insertions, 0 deletions

diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index 018f9ba5748..9f64c3fa461 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -3417,6 +3417,9 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
       A->render(Args, CmdArgs);
   }
 
+  if (Arg *A = Args.getLastArg(options::OPT_Rpass_EQ))
+    A->render(Args, CmdArgs);
+
   if (Args.hasArg(options::OPT_mkernel)) {
     if (!Args.hasArg(options::OPT_fapple_kext) && types::isCXX(InputType))
       CmdArgs.push_back("-fapple-kext");