1 /* Definitions used by AArch64 indirect function resolvers. 2 Copyright (C) 2019-2022 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 5 The GNU C Library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 The GNU C Library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with the GNU C Library; if not, see 17 <https://www.gnu.org/licenses/>. */ 18 19 #ifndef _SYS_IFUNC_H 20 #define _SYS_IFUNC_H 21 22 /* A second argument is passed to the ifunc resolver. */ 23 #define _IFUNC_ARG_HWCAP (1ULL << 62) 24 25 /* The prototype of a gnu indirect function resolver on AArch64 is 26 27 ElfW(Addr) ifunc_resolver (uint64_t, const __ifunc_arg_t *); 28 29 the first argument should have the _IFUNC_ARG_HWCAP bit set and 30 the remaining bits should match the AT_HWCAP settings. */ 31 32 /* Second argument to an ifunc resolver. */ 33 struct __ifunc_arg_t 34 { 35 unsigned long _size; /* Size of the struct, so it can grow. */ 36 unsigned long _hwcap; 37 unsigned long _hwcap2; 38 }; 39 40 typedef struct __ifunc_arg_t __ifunc_arg_t; 41 42 #endif 43