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+//=======- ASTUtis.h ---------------------------------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_ANALYZER_WEBKIT_ASTUTILS_H
+#define LLVM_CLANG_ANALYZER_WEBKIT_ASTUTILS_H
+
+#include "clang/AST/Decl.h"
+#include "llvm/ADT/APInt.h"
+#include "llvm/Support/Casting.h"
+
+#include <functional>
+#include <string>
+#include <utility>
+
+namespace clang {
+class Expr;
+
+/// This function de-facto defines a set of transformations that we consider
+/// safe (in heuristical sense). These transformation if passed a safe value as
+/// an input should provide a safe value (or an object that provides safe
+/// values).
+///
+/// For more context see Static Analyzer checkers documentation - specifically
+/// webkit.UncountedCallArgsChecker checker. Allowed list of transformations:
+/// - constructors of ref-counted types (including factory methods)
+/// - getters of ref-counted types
+/// - member overloaded operators
+/// - casts
+/// - unary operators like ``&`` or ``*``
+///
+/// If passed expression is of type uncounted pointer/reference we try to find
+/// the "origin" of the pointer value.
+/// Origin can be for example a local variable, nullptr, constant or
+/// this-pointer.
+///
+/// Certain subexpression nodes represent transformations that don't affect
+/// where the memory address originates from. We try to traverse such
+/// subexpressions to get to the relevant child nodes. Whenever we encounter a
+/// subexpression that either can't be ignored, we don't model its semantics or
+/// that has multiple children we stop.
+///
+/// \p E is an expression of uncounted pointer/reference type.
+/// If \p StopAtFirstRefCountedObj is true and we encounter a subexpression that
+/// represents ref-counted object during the traversal we return relevant
+/// sub-expression and true.
+///
+/// Calls \p callback with the subexpression that we traversed to and if \p
+/// StopAtFirstRefCountedObj is true we also specify whether we stopped early.
+/// Returns false if any of calls to callbacks returned false. Otherwise true.
+bool tryToFindPtrOrigin(
+    const clang::Expr *E, bool StopAtFirstRefCountedObj,
+    std::function<bool(const clang::Expr *, bool)> callback);
+
+/// For \p E referring to a ref-countable/-counted pointer/reference we return
+/// whether it's a safe call argument. Examples: function parameter or
+/// this-pointer. The logic relies on the set of recursive rules we enforce for
+/// WebKit codebase.
+///
+/// \returns Whether \p E is a safe call arugment.
+bool isASafeCallArg(const clang::Expr *E);
+
+/// \returns name of AST node or empty string.
+template <typename T> std::string safeGetName(const T *ASTNode) {
+  const auto *const ND = llvm::dyn_cast_or_null<clang::NamedDecl>(ASTNode);
+  if (!ND)
+    return "";
+
+  // In case F is for example "operator|" the getName() method below would
+  // assert.
+  if (!ND->getDeclName().isIdentifier())
+    return "";
+
+  return ND->getName().str();
+}
+
+} // namespace clang
+
+#endif