| Peter Collingbourne | a5c4b17 | 2020-10-30 11:38:55 -0700 | [diff] [blame] | 1 | /* | 
|  | 2 | * Copyright (C) 2020 The Android Open Source Project | 
|  | 3 | * All rights reserved. | 
|  | 4 | * | 
|  | 5 | * Redistribution and use in source and binary forms, with or without | 
|  | 6 | * modification, are permitted provided that the following conditions | 
|  | 7 | * are met: | 
|  | 8 | *  * Redistributions of source code must retain the above copyright | 
|  | 9 | *    notice, this list of conditions and the following disclaimer. | 
|  | 10 | *  * Redistributions in binary form must reproduce the above copyright | 
|  | 11 | *    notice, this list of conditions and the following disclaimer in | 
|  | 12 | *    the documentation and/or other materials provided with the | 
|  | 13 | *    distribution. | 
|  | 14 | * | 
|  | 15 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS | 
|  | 16 | * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT | 
|  | 17 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS | 
|  | 18 | * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE | 
|  | 19 | * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, | 
|  | 20 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, | 
|  | 21 | * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS | 
|  | 22 | * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED | 
|  | 23 | * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, | 
|  | 24 | * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT | 
|  | 25 | * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | 
|  | 26 | * SUCH DAMAGE. | 
|  | 27 | */ | 
|  | 28 |  | 
|  | 29 | #pragma once | 
|  | 30 |  | 
|  | 31 | #include <stddef.h> | 
|  | 32 |  | 
|  | 33 | inline uintptr_t __bionic_clear_pac_bits(uintptr_t ptr) { | 
|  | 34 | #if defined(__aarch64__) | 
|  | 35 | register uintptr_t x30 __asm("x30") = ptr; | 
|  | 36 | // This is a NOP on pre-Armv8.3-A architectures. | 
|  | 37 | asm("xpaclri" : "+r"(x30)); | 
|  | 38 | return x30; | 
|  | 39 | #else | 
|  | 40 | return ptr; | 
|  | 41 | #endif | 
|  | 42 | } |