[clang] [clang][SYCL] Diagnose reference kernel arguments (PR #192957)

[Mariya Podchishchaeva via cfe-commits]

================
@@ -0,0 +1,129 @@
+//===---------- SubobjectVisitor.h - Subobject Visitor ----------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines the SubobjectVisitor interface, which recursively
+//  traverses subobjects within a type.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_AST_SUBOBJECTVISITOR_H
+#define LLVM_CLANG_AST_SUBOBJECTVISITOR_H
+
+#include "clang/AST/Type.h"
+
+namespace clang {
+
+#define DISPATCH(CLASS)                                                        \
+  return static_cast<Derived *>(this)->visit##CLASS(                           \
+      static_cast<const CLASS *>(T))
+
+template <template <typename> class Ptr, typename Derived>
+class SubobjectVisitorBase {
+  ASTContext &Ctx;
+  template <typename Class> using ptr_t = typename Ptr<Class>::type;
+  template <typename Class>
+  using non_ptr_t = typename std::remove_pointer<ptr_t<Class>>::type;
+
+public:
+  SubobjectVisitorBase(ASTContext &Ctx) : Ctx(Ctx) {}
+
+  /// Return a reference to the derived class.
+  Derived &getDerived() { return *static_cast<Derived *>(this); }
+
+  void visit(QualType QT) {
+    // If the type is an array, visit its element type. Separate traversal of
+    // arrays is not needed because the array will be encountered as a
+    // FieldDecl.
+
+    if (QT->isArrayType()) {
+      QualType ElTy =
+          cast<ConstantArrayType>(Ctx.getAsArrayType(QT))->getElementType();
+      visit(ElTy);
+      return;
+    }
+
+    if (ptr_t<RecordDecl> RD = QT->getAsRecordDecl()) {
+      traverseRecord(RD);
+      return;
+    }
+
+    visitGenericType(QT.getCanonicalType().getTypePtr());
+  }
+
+  void traverseRecord(ptr_t<RecordDecl> RD) {
+    if (ptr_t<CXXRecordDecl> CRD = dyn_cast<CXXRecordDecl>(RD)) {
+      for (non_ptr_t<CXXBaseSpecifier> BS : CRD->bases()) {
+        if (!static_cast<Derived *>(this)->visitBaseSpecifierPre(BS))
+          continue;
+        visit(BS.getType());
+        static_cast<Derived *>(this)->visitBaseSpecifierPost(BS);
+      }
+    }
+    for (ptr_t<FieldDecl> FD : RD->fields()) {
+      if (!static_cast<Derived *>(this)->visitFieldDeclPre(FD))
+        continue;
+      visit(FD->getType());
+      static_cast<Derived *>(this)->visitFieldDeclPost(FD);
+    }
+  }
+
+  // Default base class specifier pre-order visitor.
+  bool visitBaseSpecifierPre(non_ptr_t<CXXBaseSpecifier> BS) { return true; }
+
+  // Default base class specifier post-order visitor.
+  void visitBaseSpecifierPost(non_ptr_t<CXXBaseSpecifier> BS) {}
+
+  // Default field pre-order visitor.
+  bool visitFieldDeclPre(ptr_t<FieldDecl> FD) { return true; }
+
+  // Default field post-order visitor.
+  void visitFieldDeclPost(ptr_t<FieldDecl> FD) {}
+  bool visitGenericType(const Type *T) {
+    // Top switch stmt: dispatch to VisitFooType for each FooType.
+    switch (T->getTypeClass()) {
+#define ABSTRACT_TYPE(CLASS, PARENT)
+#define TYPE(CLASS, PARENT)                                                    \
+  case Type::CLASS:                                                            \
+    DISPATCH(CLASS##Type);
+#include "clang/AST/TypeNodes.inc"
+    }
+    llvm_unreachable("Unknown type class!");
+  }
+
+  // If the implementation chooses not to implement a certain visit method, fall
+  // back on superclass.
+#define TYPE(CLASS, PARENT)                                                    \
+  bool visit##CLASS##Type(const CLASS##Type *T) { DISPATCH(PARENT); }
+#include "clang/AST/TypeNodes.inc"
+
+  /// Method called if \c ImpClass doesn't provide specific handler
+  /// for some type class.
+  bool visitType(const Type *) { return true; }
----------------
Fznamznon wrote:

Yep

https://github.com/llvm/llvm-project/pull/192957