[DebugInfo] Added support to Clang FE for generating debug info for preprocessor macros.

Added "-fdebug-macro" flag (and "-fno-debug-macro" flag) to enable (and to disable) emitting macro debug info.
Added CC1 "-debug-info-macro" flag that enables emitting macro debug info.

Differential Revision: https://reviews.llvm.org/D16135

llvm-svn: 294637

1 files changed, 14 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CodeGenAction.cpp b/clang/lib/CodeGen/CodeGenAction.cpp
index 3828c5e1701..89a7c7c727b 100644
--- a/clang/lib/CodeGen/CodeGenAction.cpp
+++ b/clang/lib/CodeGen/CodeGenAction.cpp
@@ -10,6 +10,7 @@
 #include "clang/CodeGen/CodeGenAction.h"
 #include "CodeGenModule.h"
 #include "CoverageMappingGen.h"
+#include "MacroPPCallbacks.h"
 #include "clang/AST/ASTConsumer.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/DeclCXX.h"
@@ -97,6 +98,8 @@ namespace clang {
       return std::unique_ptr<llvm::Module>(Gen->ReleaseModule());
     }
 
+    CodeGenerator *getCodeGenerator() { return Gen.get(); }
+
     void HandleCXXStaticMemberVarInstantiation(VarDecl *VD) override {
       Gen->HandleCXXStaticMemberVarInstantiation(VD);
     }
@@ -830,6 +833,17 @@ CodeGenAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
       CI.getLangOpts(), CI.getFrontendOpts().ShowTimers, InFile,
       std::move(LinkModules), std::move(OS), *VMContext, CoverageInfo));
   BEConsumer = Result.get();
+
+  // Enable generating macro debug info only when debug info is not disabled and
+  // also macro debug info is enabled.
+  if (CI.getCodeGenOpts().getDebugInfo() != codegenoptions::NoDebugInfo &&
+      CI.getCodeGenOpts().MacroDebugInfo) {
+    std::unique_ptr<PPCallbacks> Callbacks =
+        llvm::make_unique<MacroPPCallbacks>(BEConsumer->getCodeGenerator(),
+                                            CI.getPreprocessor());
+    CI.getPreprocessor().addPPCallbacks(std::move(Callbacks));
+  }
+
   return std::move(Result);
 }