[-fms-extensions] Add support for __FUNCDNAME__

Summary:
Similar to __FUNCTION__, MSVC exposes the name of the enclosing mangled
function name via __FUNCDNAME__.  This implementation is very naive and
unoptimized, it is expected that __FUNCDNAME__ would be used rarely in
practice.

Reviewers: rnk, rsmith, thakis

CC: cfe-commits, silvas

Differential Revision: http://llvm-reviews.chandlerc.com/D2109

llvm-svn: 194181

clang/include/clang/AST/Expr.h

@@ -1150,6 +1150,7 @@ public:
     Func,
     Function,
     LFunction,  // Same as Function, but as wide string.
+    FuncDName,
     PrettyFunction,
     /// PrettyFunctionNoVirtual - The same as PrettyFunction, except that the
     /// 'virtual' keyword is omitted for virtual member functions.

clang/include/clang/Basic/TokenKinds.def

@@ -349,6 +349,7 @@ KEYWORD(__PRETTY_FUNCTION__         , KEYALL)
 KEYWORD(typeof                      , KEYGNU)
 
 // MS Extensions
+KEYWORD(__FUNCDNAME__               , KEYMS)
 KEYWORD(L__FUNCTION__               , KEYMS)
 KEYWORD(__is_interface_class        , KEYMS)
 KEYWORD(__is_sealed                 , KEYMS)

clang/lib/AST/ASTDumper.cpp

@@ -1661,6 +1661,7 @@ void ASTDumper::VisitPredefinedExpr(const PredefinedExpr *Node) {
   default: llvm_unreachable("unknown case");
   case PredefinedExpr::Func:           OS <<  " __func__"; break;
   case PredefinedExpr::Function:       OS <<  " __FUNCTION__"; break;
+  case PredefinedExpr::FuncDName:      OS <<  " __FUNCDNAME__"; break;
   case PredefinedExpr::LFunction:      OS <<  " L__FUNCTION__"; break;
   case PredefinedExpr::PrettyFunction: OS <<  " __PRETTY_FUNCTION__";break;
   }

clang/lib/AST/Expr.cpp

@@ -20,6 +20,7 @@
 #include "clang/AST/EvaluatedExprVisitor.h"
 #include "clang/AST/Expr.h"
 #include "clang/AST/ExprCXX.h"
+#include "clang/AST/Mangle.h"
 #include "clang/AST/RecordLayout.h"
 #include "clang/AST/StmtVisitor.h"
 #include "clang/Basic/Builtins.h"
@@ -478,6 +479,30 @@ SourceLocation DeclRefExpr::getLocEnd() const {
 std::string PredefinedExpr::ComputeName(IdentType IT, const Decl *CurrentDecl) {
   ASTContext &Context = CurrentDecl->getASTContext();
 
+  if (IT == PredefinedExpr::FuncDName) {
+    if (const NamedDecl *ND = dyn_cast<NamedDecl>(CurrentDecl)) {
+      OwningPtr<MangleContext> MC;
+      MC.reset(Context.createMangleContext());
+
+      if (MC->shouldMangleDeclName(ND)) {
+        SmallString<256> Buffer;
+        llvm::raw_svector_ostream Out(Buffer);
+        if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(ND))
+          MC->mangleCXXCtor(CD, Ctor_Base, Out);
+        else if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(ND))
+          MC->mangleCXXDtor(DD, Dtor_Base, Out);
+        else
+          MC->mangleName(ND, Out);
+
+        Out.flush();
+        if (!Buffer.empty() && Buffer.front() == '\01')
+          return Buffer.substr(1);
+        return Buffer.str();
+      } else
+        return ND->getIdentifier()->getName();
+    }
+    return "";
+  }
   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(CurrentDecl)) {
     if (IT != PrettyFunction && IT != PrettyFunctionNoVirtual)
       return FD->getNameAsString();

clang/lib/AST/StmtPrinter.cpp

@@ -738,6 +738,9 @@ void StmtPrinter::VisitPredefinedExpr(PredefinedExpr *Node) {
     case PredefinedExpr::Function:
       OS << "__FUNCTION__";
       break;
+    case PredefinedExpr::FuncDName:
+      OS << "__FUNCDNAME__";
+      break;
     case PredefinedExpr::LFunction:
       OS << "L__FUNCTION__";
       break;

clang/lib/CodeGen/CGExpr.cpp

@@ -1944,6 +1944,7 @@ LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) {
   case PredefinedExpr::Func:
   case PredefinedExpr::Function:
   case PredefinedExpr::LFunction:
+  case PredefinedExpr::FuncDName:
   case PredefinedExpr::PrettyFunction: {
     PredefinedExpr::IdentType IdentType = E->getIdentType();
     std::string GlobalVarName;
@@ -1956,6 +1957,9 @@ LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) {
     case PredefinedExpr::Function:
       GlobalVarName = "__FUNCTION__.";
       break;
+    case PredefinedExpr::FuncDName:
+      GlobalVarName = "__FUNCDNAME__.";
+      break;
     case PredefinedExpr::LFunction:
       GlobalVarName = "L__FUNCTION__.";
       break;

clang/lib/Parse/ParseExpr.cpp

@@ -491,6 +491,8 @@ class CastExpressionIdValidator : public CorrectionCandidateCallback {
 /// [C11]   generic-selection
 ///         '__func__'        [C99 6.4.2.2]
 /// [GNU]   '__FUNCTION__'
+/// [MS]    '__FUNCDNAME__'
+/// [MS]    'L__FUNCTION__'
 /// [GNU]   '__PRETTY_FUNCTION__'
 /// [GNU]   '(' compound-statement ')'
 /// [GNU]   '__builtin_va_arg' '(' assignment-expression ',' type-name ')'
@@ -870,6 +872,7 @@ ExprResult Parser::ParseCastExpression(bool isUnaryExpression,
     break;
   case tok::kw___func__:       // primary-expression: __func__ [C99 6.4.2.2]
   case tok::kw___FUNCTION__:   // primary-expression: __FUNCTION__ [GNU]
+  case tok::kw___FUNCDNAME__:   // primary-expression: __FUNCDNAME__ [MS]
   case tok::kw_L__FUNCTION__:   // primary-expression: L__FUNCTION__ [MS]
   case tok::kw___PRETTY_FUNCTION__:  // primary-expression: __P..Y_F..N__ [GNU]
     Res = Actions.ActOnPredefinedExpr(Tok.getLocation(), SavedKind);

clang/lib/Parse/ParseTentative.cpp

@@ -940,6 +940,7 @@ Parser::isExpressionOrTypeSpecifierSimple(tok::TokenKind Kind) {
   case tok::kw___imag:
   case tok::kw___real:
   case tok::kw___FUNCTION__:
+  case tok::kw___FUNCDNAME__:
   case tok::kw_L__FUNCTION__:
   case tok::kw___PRETTY_FUNCTION__:
   case tok::kw___has_nothrow_assign:

clang/lib/Sema/SemaExpr.cpp

@@ -2855,6 +2855,7 @@ ExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, tok::TokenKind Kind) {
   default: llvm_unreachable("Unknown simple primary expr!");
   case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2]
   case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break;
+  case tok::kw___FUNCDNAME__: IT = PredefinedExpr::FuncDName; break; // [MS]
   case tok::kw_L__FUNCTION__: IT = PredefinedExpr::LFunction; break;
   case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break;
   }