Parser support for #pragma clang __debug captured

This patch implements parsing ‘#pragma clang __debug’ as a first step for
implementing captured statements. Captured statements are a mechanism for
doing outlining in the AST.
see http://lists.cs.uiuc.edu/pipermail/cfe-dev/2013-January/027540.html.

Currently returns StmtEmpty

Author: Andy Zhang <andy.zhang@intel.com>

Differential Revision: http://llvm-reviews.chandlerc.com/D369


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179614 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 60 insertions, 0 deletions

diff --git a/lib/Frontend/PrintPreprocessedOutput.cpp b/lib/Frontend/PrintPreprocessedOutput.cpp
index 432428bb96..6734d7759b 100644
--- a/lib/Frontend/PrintPreprocessedOutput.cpp
+++ b/lib/Frontend/PrintPreprocessedOutput.cpp
@@ -140,6 +140,7 @@ public:
   virtual void PragmaComment(SourceLocation Loc, const IdentifierInfo *Kind,
                              const std::string &Str);
   virtual void PragmaMessage(SourceLocation Loc, StringRef Str);
+  virtual void PragmaDebug(SourceLocation Loc, StringRef DebugType);
   virtual void PragmaDiagnosticPush(SourceLocation Loc,
                                     StringRef Namespace);
   virtual void PragmaDiagnosticPop(SourceLocation Loc,
@@ -419,6 +420,17 @@ void PrintPPOutputPPCallbacks::PragmaMessage(SourceLocation Loc,
   setEmittedDirectiveOnThisLine();
 }
 
+void PrintPPOutputPPCallbacks::PragmaDebug(SourceLocation Loc,
+                                           StringRef DebugType) {
+  startNewLineIfNeeded();
+  MoveToLine(Loc);
+
+  OS << "#pragma clang __debug ";
+  OS << DebugType;
+
+  setEmittedDirectiveOnThisLine();
+}
+
 void PrintPPOutputPPCallbacks::
 PragmaDiagnosticPush(SourceLocation Loc, StringRef Namespace) {
   startNewLineIfNeeded();
diff --git a/lib/Lex/Pragma.cpp b/lib/Lex/Pragma.cpp
index 95e8a8ca8f..af58c50f05 100644
--- a/lib/Lex/Pragma.cpp
+++ b/lib/Lex/Pragma.cpp
@@ -995,10 +995,40 @@ struct PragmaDebugHandler : public PragmaHandler {
       llvm::CrashRecoveryContext *CRC =llvm::CrashRecoveryContext::GetCurrent();
       if (CRC)
         CRC->HandleCrash();
+    } else if (II->isStr("captured")) {
+      HandleCaptured(PP);
     } else {
       PP.Diag(Tok, diag::warn_pragma_debug_unexpected_command)
         << II->getName();
     }
+
+    PPCallbacks *Callbacks = PP.getPPCallbacks();
+    if (Callbacks)
+      Callbacks->PragmaDebug(Tok.getLocation(), II->getName());
+  }
+
+  void HandleCaptured(Preprocessor &PP) {
+    // Skip if emitting preprocessed output.
+    if (PP.isPreprocessedOutput())
+      return;
+
+    Token Tok;
+    PP.LexUnexpandedToken(Tok);
+
+    if (Tok.isNot(tok::eod)) {
+      PP.Diag(Tok, diag::ext_pp_extra_tokens_at_eol)
+        << "pragma clang __debug captured";
+      return;
+    }
+
+    SourceLocation NameLoc = Tok.getLocation();
+    Token *Toks = PP.getPreprocessorAllocator().Allocate<Token>(1);
+    Toks->startToken();
+    Toks->setKind(tok::annot_pragma_captured);
+    Toks->setLocation(NameLoc);
+
+    PP.EnterTokenStream(Toks, 1, /*DisableMacroExpansion=*/true,
+                        /*OwnsTokens=*/false);
   }
 
 // Disable MSVC warning about runtime stack overflow.
diff --git a/lib/Parse/ParsePragma.cpp b/lib/Parse/ParsePragma.cpp
index dc6b3ed4fa..038636d108 100644
--- a/lib/Parse/ParsePragma.cpp
+++ b/lib/Parse/ParsePragma.cpp
@@ -122,6 +122,19 @@ void Parser::HandlePragmaFPContract() {
   ConsumeToken(); // The annotation token.
 }
 
+StmtResult Parser::HandlePragmaCaptured()
+{
+  assert(Tok.is(tok::annot_pragma_captured));
+  ConsumeToken();
+
+  if (Tok.isNot(tok::l_brace)) {
+    PP.Diag(Tok, diag::err_expected_lbrace);
+    return StmtError();
+  }
+
+  return StmtEmpty();
+}
+
 namespace {
   typedef llvm::PointerIntPair<IdentifierInfo *, 1, bool> OpenCLExtData;
 }
@@ -151,6 +164,8 @@ void Parser::HandlePragmaOpenCLExtension() {
   }
 }
 
+
+
 // #pragma GCC visibility comes in two variants:
 //   'push' '(' [visibility] ')'
 //   'pop'
diff --git a/lib/Parse/ParseStmt.cpp b/lib/Parse/ParseStmt.cpp
index 355f3694bb..5fa4f17026 100644
--- a/lib/Parse/ParseStmt.cpp
+++ b/lib/Parse/ParseStmt.cpp
@@ -289,6 +289,9 @@ Retry:
     HandlePragmaOpenCLExtension();
     return StmtEmpty();
 
+  case tok::annot_pragma_captured:
+    return HandlePragmaCaptured();
+
   case tok::annot_pragma_openmp:
     SourceLocation DeclStart = Tok.getLocation();
     DeclGroupPtrTy Res = ParseOpenMPDeclarativeDirective();