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1//===-- sanitizer_ptrauth.h -------------------------------------*- C++ -*-===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef SANITIZER_PTRAUTH_H10#define SANITIZER_PTRAUTH_H11 12#if __has_feature(ptrauth_intrinsics)13# include <ptrauth.h>14#elif defined(__ARM_FEATURE_PAC_DEFAULT) && !defined(__APPLE__)15// On the stack the link register is protected with Pointer16// Authentication Code when compiled with -mbranch-protection.17// Let's stripping the PAC unconditionally because xpaclri is in18// the NOP space so will do nothing when it is not enabled or not available.19# define ptrauth_strip(__value, __key) \20 ({ \21 __typeof(__value) ret; \22 asm volatile( \23 "mov x30, %1\n\t" \24 "hint #7\n\t" \25 "mov %0, x30\n\t" \26 "mov x30, xzr\n\t" \27 : "=r"(ret) \28 : "r"(__value) \29 : "x30"); \30 ret; \31 })32# define ptrauth_auth_data(__value, __old_key, __old_data) __value33# define ptrauth_string_discriminator(__string) ((int)0)34#else35// Copied from <ptrauth.h>36# define ptrauth_strip(__value, __key) __value37# define ptrauth_auth_data(__value, __old_key, __old_data) __value38# define ptrauth_string_discriminator(__string) ((int)0)39#endif40 41#define STRIP_PAC_PC(pc) ((uptr)ptrauth_strip(pc, 0))42 43#endif // SANITIZER_PTRAUTH_H44