Update prebuilt Clang to r416183b from Android.

https://android.googlesource.com/platform/prebuilts/clang/host/
linux-x86/+/06a71ddac05c22edb2d10b590e1769b3f8619bef

clang 12.0.5 (based on r416183b) from build 7284624.

Change-Id: I277a316abcf47307562d8b748b84870f31a72866
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/linux-x64/clang/include/clang-tidy/utils/DeclRefExprUtils.h b/linux-x64/clang/include/clang-tidy/utils/DeclRefExprUtils.h
new file mode 100644
index 0000000..abf3529
--- /dev/null
+++ b/linux-x64/clang/include/clang-tidy/utils/DeclRefExprUtils.h
@@ -0,0 +1,59 @@
+//===--- DeclRefExprUtils.h - clang-tidy-------------------------*- 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_TOOLS_EXTRA_CLANG_TIDY_UTILS_DECLREFEXPRUTILS_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_UTILS_DECLREFEXPRUTILS_H
+
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/Type.h"
+#include "llvm/ADT/SmallPtrSet.h"
+
+namespace clang {
+namespace tidy {
+namespace utils {
+namespace decl_ref_expr {
+
+/// Returns true if all ``DeclRefExpr`` to the variable within ``Stmt``
+/// do not modify it.
+///
+/// Returns ``true`` if only const methods or operators are called on the
+/// variable or the variable is a const reference or value argument to a
+/// ``callExpr()``.
+bool isOnlyUsedAsConst(const VarDecl &Var, const Stmt &Stmt,
+                       ASTContext &Context);
+
+/// Returns set of all ``DeclRefExprs`` to ``VarDecl`` within ``Stmt``.
+llvm::SmallPtrSet<const DeclRefExpr *, 16>
+allDeclRefExprs(const VarDecl &VarDecl, const Stmt &Stmt, ASTContext &Context);
+
+/// Returns set of all ``DeclRefExprs`` to ``VarDecl`` within ``Decl``.
+llvm::SmallPtrSet<const DeclRefExpr *, 16>
+allDeclRefExprs(const VarDecl &VarDecl, const Decl &Decl, ASTContext &Context);
+
+/// Returns set of all ``DeclRefExprs`` to ``VarDecl`` within ``Stmt`` where
+/// ``VarDecl`` is guaranteed to be accessed in a const fashion.
+llvm::SmallPtrSet<const DeclRefExpr *, 16>
+constReferenceDeclRefExprs(const VarDecl &VarDecl, const Stmt &Stmt,
+                           ASTContext &Context);
+
+/// Returns ``true`` if ``DeclRefExpr`` is the argument of a copy-constructor
+/// call expression within ``Decl``.
+bool isCopyConstructorArgument(const DeclRefExpr &DeclRef, const Decl &Decl,
+                               ASTContext &Context);
+
+/// Returns ``true`` if ``DeclRefExpr`` is the argument of a copy-assignment
+/// operator CallExpr within ``Decl``.
+bool isCopyAssignmentArgument(const DeclRefExpr &DeclRef, const Decl &Decl,
+                              ASTContext &Context);
+
+} // namespace decl_ref_expr
+} // namespace utils
+} // namespace tidy
+} // namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_UTILS_DECLREFEXPRUTILS_H