[clang] Use llvm::iterator_range::empty (NFC)

clang/lib/CodeGen/CGDebugInfo.cpp

@@ -2874,7 +2874,7 @@ static bool isDefinedInClangModule(const RecordDecl *RD) {
       if (!Explicit && CXXDecl->getEnclosingNamespaceContext())
         return false;
       // This is a template, check the origin of the first member.
-      if (CXXDecl->field_begin() == CXXDecl->field_end())
+      if (CXXDecl->fields().empty())
         return TemplateKind == TSK_ExplicitInstantiationDeclaration;
       if (!CXXDecl->field_begin()->isFromASTFile())
         return false;

clang/lib/CodeGen/CGExprCXX.cpp

@@ -373,7 +373,7 @@ RValue CodeGenFunction::EmitCXXMemberOrOperatorMemberCallExpr(
   bool UseVirtualCall = CanUseVirtualCall && !DevirtualizedMethod;
 
   if (const CXXDestructorDecl *Dtor = dyn_cast<CXXDestructorDecl>(CalleeDecl)) {
-    assert(CE->arg_begin() == CE->arg_end() &&
+    assert(CE->arguments().empty() &&
            "Destructor shouldn't have explicit parameters");
     assert(ReturnValue.isNull() && "Destructor shouldn't have return value");
     if (UseVirtualCall) {

clang/lib/CodeGen/CGObjCGNU.cpp

@@ -1750,7 +1750,7 @@ class CGObjCGNUstep2 : public CGObjCGNUstep {
     // struct objc_method_list *methods
     // FIXME: Almost identical code is copied and pasted below for the
     // class, but refactoring it cleanly requires C++14 generic lambdas.
-    if (OID->classmeth_begin() == OID->classmeth_end())
+    if (OID->class_methods().empty())
       metaclassFields.addNullPointer(PtrTy);
     else {
       SmallVector<ObjCMethodDecl*, 16> ClassMethods;

clang/lib/CodeGen/CodeGenTBAA.cpp

@@ -439,7 +439,7 @@ CodeGenTBAA::CollectFields(uint64_t BaseOffset,
 
     // TODO: Handle C++ base classes.
     if (const CXXRecordDecl *Decl = dyn_cast<CXXRecordDecl>(RD))
-      if (Decl->bases_begin() != Decl->bases_end())
+      if (!Decl->bases().empty())
         return false;
 
     const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);

clang/lib/CodeGen/ItaniumCXXABI.cpp

@@ -2262,7 +2262,7 @@ llvm::Value *ItaniumCXXABI::EmitVirtualDestructorCall(
   auto *CE = dyn_cast<const CXXMemberCallExpr *>(E);
   auto *D = dyn_cast<const CXXDeleteExpr *>(E);
   assert((CE != nullptr) ^ (D != nullptr));
-  assert(CE == nullptr || CE->arg_begin() == CE->arg_end());
+  assert(CE == nullptr || CE->arguments().empty());
   assert(DtorType == Dtor_Deleting || DtorType == Dtor_Complete);
 
   GlobalDecl GD(Dtor, DtorType);

clang/lib/CodeGen/MicrosoftCXXABI.cpp

@@ -2000,7 +2000,7 @@ llvm::Value *MicrosoftCXXABI::EmitVirtualDestructorCall(
   auto *CE = dyn_cast<const CXXMemberCallExpr *>(E);
   auto *D = dyn_cast<const CXXDeleteExpr *>(E);
   assert((CE != nullptr) ^ (D != nullptr));
-  assert(CE == nullptr || CE->arg_begin() == CE->arg_end());
+  assert(CE == nullptr || CE->arguments().empty());
   assert(DtorType == Dtor_Deleting || DtorType == Dtor_Complete);
 
   // We have only one destructor in the vftable but can get both behaviors