Introduce FunctionDecl::getFirstDeclaration() and VarDecl::getFirstDeclaration().

For multiple redeclarations they return the first one.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@75602 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 26 insertions, 10 deletions

diff --git a/include/clang/AST/Decl.h b/include/clang/AST/Decl.h
index d033c24046..e83833f7d9 100644
--- a/include/clang/AST/Decl.h
+++ b/include/clang/AST/Decl.h
@@ -413,6 +413,10 @@ public:
     PreviousDeclaration = PrevDecl;
   }
 
+  /// \brief For multiple redeclarations returns the first one, otherwise
+  /// returns itself.
+  const VarDecl *getFirstDeclaration() const;
+
   virtual Decl *getPrimaryDecl() const;
 
   /// hasLocalStorage - Returns true if a variable with function scope
@@ -811,6 +815,10 @@ public:
     return PreviousDeclaration;
   }
 
+  /// \brief For multiple redeclarations returns the first one, otherwise
+  /// returns itself.
+  const FunctionDecl *getFirstDeclaration() const;
+
   void setPreviousDeclaration(FunctionDecl * PrevDecl);
 
   virtual Decl *getPrimaryDecl() const;
diff --git a/lib/AST/Decl.cpp b/lib/AST/Decl.cpp
index fe9885ef26..5ef0c09093 100644
--- a/lib/AST/Decl.cpp
+++ b/lib/AST/Decl.cpp
@@ -358,12 +358,16 @@ const Expr *VarDecl::getDefinition(const VarDecl *&Def) const {
   return Def? Def->getInit() : 0;
 }
 
-Decl *VarDecl::getPrimaryDecl() const {
-  const VarDecl *Prim = this;
-  while (Prim->getPreviousDeclaration())
-    Prim = Prim->getPreviousDeclaration();
+const VarDecl *VarDecl::getFirstDeclaration() const {
+  const VarDecl *First = this;
+  while (First->getPreviousDeclaration())
+    First = First->getPreviousDeclaration();
+
+  return First;
+}
 
-  return const_cast<VarDecl *>(Prim);
+Decl *VarDecl::getPrimaryDecl() const {
+  return const_cast<VarDecl *>(getFirstDeclaration());
 }
 
 //===----------------------------------------------------------------------===//
@@ -577,12 +581,16 @@ FunctionDecl::setPreviousDeclaration(FunctionDecl *PrevDecl) {
   }
 }
 
-Decl *FunctionDecl::getPrimaryDecl() const {
-  const FunctionDecl *Prim = this;
-  while (Prim->getPreviousDeclaration())
-    Prim = Prim->getPreviousDeclaration();
+const FunctionDecl *FunctionDecl::getFirstDeclaration() const {
+  const FunctionDecl *First = this;
+  while (First->getPreviousDeclaration())
+    First = First->getPreviousDeclaration();
+
+  return First;
+}
 
-  return const_cast<FunctionDecl *>(Prim);
+Decl *FunctionDecl::getPrimaryDecl() const {
+  return const_cast<FunctionDecl *>(getFirstDeclaration());
 }
 
 /// getOverloadedOperator - Which C++ overloaded operator this