Thread safety: added support for function scopes in attribute arguments.

This patch was written by DeLesley Hutchins.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@139302 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/AST/DeclBase.h

@@ -671,6 +671,9 @@ public:
   /// \brief Whether this declaration is a parameter pack.
   bool isParameterPack() const;
   
+  /// \brief returns true if this declaration is a template
+  bool isTemplateDecl() const;
+
   /// \brief Whether this declaration is a function or function template.
   bool isFunctionOrFunctionTemplate() const;
 

include/clang/Sema/Sema.h

@@ -1244,6 +1244,10 @@ public:
   void EnterDeclaratorContext(Scope *S, DeclContext *DC);
   void ExitDeclaratorContext(Scope *S);
 
+  /// Push the parameters of D, which must be a function, into scope.
+  void ActOnReenterFunctionContext(Scope* S, Decl* D);
+  void ActOnExitFunctionContext() { PopDeclContext(); }
+
   DeclContext *getFunctionLevelDeclContext();
 
   /// getCurFunctionDecl - If inside of a function body, this returns a pointer

lib/AST/DeclBase.cpp

@@ -133,6 +133,10 @@ bool Decl::isFunctionOrFunctionTemplate() const {
   return isa<FunctionDecl>(this) || isa<FunctionTemplateDecl>(this);
 }
 
+bool Decl::isTemplateDecl() const {
+  return isa<TemplateDecl>(this);
+}
+
 bool Decl::isDefinedOutsideFunctionOrMethod() const {
   for (const DeclContext *DC = getDeclContext(); 
        DC && !DC->isTranslationUnit(); 

lib/Parse/ParseDecl.cpp

@@ -759,8 +759,28 @@ void Parser::ParseLexedAttribute(LateParsedAttribute &LA) {
   ParsedAttributes Attrs(AttrFactory);
   SourceLocation endLoc;
 
+  // If the Decl is templatized, add template parameters to scope.
+  bool HasTemplateScope = LA.D && LA.D->isTemplateDecl();
+  ParseScope TempScope(this, Scope::TemplateParamScope, HasTemplateScope);
+  if (HasTemplateScope)
+    Actions.ActOnReenterTemplateScope(Actions.CurScope, LA.D);
+
+  // If the Decl is on a function, add function parameters to the scope.
+  bool HasFunctionScope = LA.D && LA.D->isFunctionOrFunctionTemplate();
+  ParseScope FnScope(this, Scope::FnScope|Scope::DeclScope, HasFunctionScope);
+  if (HasFunctionScope)
+    Actions.ActOnReenterFunctionContext(Actions.CurScope, LA.D);
+
   ParseGNUAttributeArgs(&LA.AttrName, LA.AttrNameLoc, Attrs, &endLoc);
 
+  if (HasFunctionScope) {
+    Actions.ActOnExitFunctionContext();
+    FnScope.Exit();  // Pop scope, and remove Decls from IdResolver
+  }
+  if (HasTemplateScope) {
+    TempScope.Exit();
+  }
+
   // Late parsed attributes must be attached to Decls by hand.  If the
   // LA.D is not set, then this was not done properly.
   assert(LA.D && "No decl attached to late parsed attribute");

lib/Sema/SemaDecl.cpp

@@ -782,6 +782,29 @@ void Sema::ExitDeclaratorContext(Scope *S) {
   // disappear.
 }
 
+
+void Sema::ActOnReenterFunctionContext(Scope* S, Decl *D) {
+  FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
+  if (FunctionTemplateDecl *TFD = dyn_cast_or_null<FunctionTemplateDecl>(D)) {
+    // We assume that the caller has already called
+    // ActOnReenterTemplateScope
+    FD = TFD->getTemplatedDecl();
+  }
+  if (!FD)
+    return;
+
+  PushDeclContext(S, FD);
+  for (unsigned P = 0, NumParams = FD->getNumParams(); P < NumParams; ++P) {
+    ParmVarDecl *Param = FD->getParamDecl(P);
+    // If the parameter has an identifier, then add it to the scope
+    if (Param->getIdentifier()) {
+      S->AddDecl(Param);
+      IdResolver.AddDecl(Param);
+    }
+  }
+}
+
+
 /// \brief Determine whether we allow overloading of the function
 /// PrevDecl with another declaration.
 ///

lib/Sema/SemaDeclAttr.cpp

@@ -304,8 +304,11 @@ static bool checkAttrArgsAreLockableObjs(Sema &S, Decl *D,
   for(unsigned Idx = Sidx; Idx < Attr.getNumArgs(); ++Idx) {
     Expr *ArgExp = Attr.getArg(Idx);
 
-    if (ArgExp->isTypeDependent())
-     continue;
+    if (ArgExp->isTypeDependent()) {
+      // FIXME -- need to processs this again on template instantiation
+      Args.push_back(ArgExp);
+      continue;
+    }
 
     QualType ArgTy = ArgExp->getType();
 
@@ -390,6 +393,7 @@ static void handleGuardedByAttr(Sema &S, Decl *D, const AttributeList &Attr,
     return;
 
   if (Arg->isTypeDependent())
+    // FIXME: handle attributes with dependent types
     return;
 
   // check that the argument is lockable object

test/SemaCXX/warn-thread-safety-parsing.cpp

@@ -1219,3 +1219,37 @@ struct Foomgoper {
 };
 
 
+//-----------------------------------------------------
+// Parsing of member variables and function parameters
+//------------------------------------------------------
+
+Mu gmu;
+
+class StaticMu {
+  static Mu statmu;
+};
+
+class FooLate {
+public:
+  void foo1()           __attribute__((exclusive_locks_required(gmu)))   { }
+  void foo2()           __attribute__((exclusive_locks_required(mu)))    { }
+  void foo3(Mu *m)      __attribute__((exclusive_locks_required(m)))     { }
+  void foo3(FooLate *f) __attribute__((exclusive_locks_required(f->mu))) { }
+  void foo4(FooLate *f) __attribute__((exclusive_locks_required(f->mu)));
+
+  static void foo5()    __attribute__((exclusive_locks_required(mu))); // \
+    expected-error {{invalid use of member 'mu' in static member function}}
+
+  template <class T>
+  void foo6() __attribute__((exclusive_locks_required(T::statmu))) { }
+
+  template <class T>
+  void foo7(T* f) __attribute__((exclusive_locks_required(f->mu))) { }
+
+  int a __attribute__((guarded_by(gmu)));
+  int b __attribute__((guarded_by(mu)));
+  int c __attribute__((guarded_by(this->mu)));
+
+  Mu mu;
+};
+