Expose Objective-C type encodings of declarations to libclang users. This also adds a method in ASTContext which encodes FunctionDecls using the same encoding format that is used for Objective-C methods.

llvm-svn: 122639

clang/include/clang-c/Index.h

@@ -1792,6 +1792,10 @@ CINDEX_LINKAGE CXType clang_getPointeeType(CXType T);
  */
 CINDEX_LINKAGE CXCursor clang_getTypeDeclaration(CXType T);
 
+/**
+ * Returns the Objective-C type encoding for the specified declaration.
+ */
+CINDEX_LINKAGE CXString clang_getDeclObjCTypeEncoding(CXCursor C);
 
 /**
  * \brief Retrieve the spelling of a given CXTypeKind.

clang/include/clang/AST/ASTContext.h

@@ -828,6 +828,10 @@ public:
   void getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
                                        std::string &S) const;
 
+  /// getObjCEncodingForFunctionDecl - Returns the encoded type for this
+  //function.  This is in the same format as Objective-C method encodings.  
+  void getObjCEncodingForFunctionDecl(const FunctionDecl *Decl, std::string& S);
+
   /// getObjCEncodingForMethodDecl - Return the encoded type for this method
   /// declaration.
   void getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl, std::string &S);

clang/lib/AST/ASTContext.cpp

@@ -3526,6 +3526,42 @@ void ASTContext::getObjCEncodingForBlock(const BlockExpr *Expr,
   }
 }
 
+void ASTContext::getObjCEncodingForFunctionDecl(const FunctionDecl *Decl,
+                                                std::string& S) {
+  // Encode result type.
+  getObjCEncodingForType(Decl->getResultType(), S);
+  CharUnits ParmOffset;
+  // Compute size of all parameters.
+  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
+       E = Decl->param_end(); PI != E; ++PI) {
+    QualType PType = (*PI)->getType();
+    CharUnits sz = getObjCEncodingTypeSize(PType);
+    assert (sz.isPositive() && 
+        "getObjCEncodingForMethodDecl - Incomplete param type");
+    ParmOffset += sz;
+  }
+  S += charUnitsToString(ParmOffset);
+  ParmOffset = CharUnits::Zero();
+
+  // Argument types.
+  for (FunctionDecl::param_const_iterator PI = Decl->param_begin(),
+       E = Decl->param_end(); PI != E; ++PI) {
+    ParmVarDecl *PVDecl = *PI;
+    QualType PType = PVDecl->getOriginalType();
+    if (const ArrayType *AT =
+          dyn_cast<ArrayType>(PType->getCanonicalTypeInternal())) {
+      // Use array's original type only if it has known number of
+      // elements.
+      if (!isa<ConstantArrayType>(AT))
+        PType = PVDecl->getType();
+    } else if (PType->isFunctionType())
+      PType = PVDecl->getType();
+    getObjCEncodingForType(PType, S);
+    S += charUnitsToString(ParmOffset);
+    ParmOffset += getObjCEncodingTypeSize(PType);
+  }
+}
+
 /// getObjCEncodingForMethodDecl - Return the encoded type for this method
 /// declaration.
 void ASTContext::getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,

clang/tools/libclang/CXType.cpp

@@ -353,4 +353,33 @@ unsigned clang_isPODType(CXType X) {
   return T->isPODType() ? 1 : 0;
 }
 
+CXString clang_getDeclObjCTypeEncoding(CXCursor C) {
+  if ((C.kind < CXCursor_FirstDecl) || (C.kind > CXCursor_LastDecl))
+    return cxstring::createCXString("");
+
+  Decl *D = static_cast<Decl*>(C.data[0]);
+  CXTranslationUnit TU = static_cast<CXTranslationUnit>(C.data[2]);
+  ASTUnit *AU = static_cast<ASTUnit*>(TU->TUData);
+  ASTContext &Ctx = AU->getASTContext();
+  std::string encoding;
+
+  if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(D)) 
+    Ctx.getObjCEncodingForMethodDecl(OMD, encoding);
+  else if (ObjCPropertyDecl *OPD = dyn_cast<ObjCPropertyDecl>(D)) 
+    Ctx.getObjCEncodingForPropertyDecl(OPD, NULL, encoding);
+  else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
+    Ctx.getObjCEncodingForFunctionDecl(FD, encoding);
+  else {
+    QualType Ty;
+    if (TypeDecl *TD = dyn_cast<TypeDecl>(D))
+      Ty = QualType(TD->getTypeForDecl(), 0);
+    if (ValueDecl *VD = dyn_cast<ValueDecl>(D))
+      Ty = VD->getType();
+    else return cxstring::createCXString("?");
+    Ctx.getObjCEncodingForType(Ty, encoding);
+  }
+
+  return cxstring::createCXString(encoding);
+}
+
 } // end: extern "C"

clang/tools/libclang/libclang.darwin.exports

@@ -61,6 +61,7 @@ _clang_getCursorSemanticParent
 _clang_getCursorSpelling
 _clang_getCursorType
 _clang_getCursorUSR
+_clang_getDeclObjCTypeEncoding
 _clang_getDefinitionSpellingAndExtent
 _clang_getDiagnostic
 _clang_getDiagnosticCategory

clang/tools/libclang/libclang.exports

@@ -61,6 +61,7 @@ clang_getCursorSemanticParent
 clang_getCursorSpelling
 clang_getCursorType
 clang_getCursorUSR
+clang_getDeclObjCTypeEncoding
 clang_getDefinitionSpellingAndExtent
 clang_getDiagnostic
 clang_getDiagnosticCategory