| /* |
| * Copyright (C) 2019 The Android Open Source Project |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in |
| * the documentation and/or other materials provided with the |
| * distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, |
| * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS |
| * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED |
| * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| */ |
| |
| #pragma once |
| |
| #include <sys/cdefs.h> |
| |
| /** |
| * @file sys/ifunc.h |
| * @brief Declarations used for ifunc resolvers. Currently only meaningful for arm64. |
| */ |
| |
| __BEGIN_DECLS |
| |
| #if defined(__aarch64__) |
| |
| /** |
| * Provides information about hardware capabilities to ifunc resolvers. |
| * |
| * Starting with API level 30, ifunc resolvers on arm64 are passed two arguments. The first is a |
| * uint64_t whose value is equal to getauxval(AT_HWCAP) | _IFUNC_ARG_HWCAP. The second is a pointer |
| * to a data structure of this type. Prior to API level 30, no arguments are passed to ifunc |
| * resolvers. Code that wishes to be compatible with prior API levels should not accept any |
| * arguments in the resolver. |
| */ |
| typedef struct __ifunc_arg_t { |
| /** Set to sizeof(__ifunc_arg_t). */ |
| unsigned long _size; |
| |
| /** Set to getauxval(AT_HWCAP). */ |
| unsigned long _hwcap; |
| |
| /** Set to getauxval(AT_HWCAP2). */ |
| unsigned long _hwcap2; |
| } __ifunc_arg_t; |
| |
| /** |
| * If this bit is set in the first argument to an ifunc resolver, indicates that the second argument |
| * is a pointer to a data structure of type __ifunc_arg_t. This bit is always set on Android |
| * starting with API level 30. |
| */ |
| #define _IFUNC_ARG_HWCAP (1ULL << 62) |
| |
| #endif |
| |
| __END_DECLS |
