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1//===-- hwasan_setjmp_aarch64.S -------------------------------------------===//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// This file is a part of HWAddressSanitizer.10//11// HWAddressSanitizer runtime.12//===----------------------------------------------------------------------===//13 14#include "sanitizer_common/sanitizer_asm.h"15#include "builtins/assembly.h"16 17#if HWASAN_WITH_INTERCEPTORS && defined(__aarch64__)18#include "sanitizer_common/sanitizer_platform.h"19 20// We want to save the context of the calling function.21// That requires22// 1) No modification of the link register by this function.23// 2) No modification of the stack pointer by this function.24// 3) (no modification of any other saved register, but that's not really going25// to occur, and hence isn't as much of a worry).26//27// There's essentially no way to ensure that the compiler will not modify the28// stack pointer when compiling a C function.29// Hence we have to write this function in assembly.30 31TEXT_SECTION32.file "hwasan_setjmp_aarch64.S"33 34.global ASM_WRAPPER_NAME(setjmp)35ASM_TYPE_FUNCTION(ASM_WRAPPER_NAME(setjmp))36ASM_WRAPPER_NAME(setjmp):37 CFI_STARTPROC38 BTI_C39 mov x1, #040 b ASM_WRAPPER_NAME(sigsetjmp)41 CFI_ENDPROC42ASM_SIZE(ASM_WRAPPER_NAME(setjmp))43 44ASM_INTERCEPTOR_TRAMPOLINE(setjmp)45 46#if SANITIZER_ANDROID47// Bionic also defines a function `setjmp` that calls `sigsetjmp` saving the48// current signal.49.global ASM_WRAPPER_NAME(setjmp_bionic)50ASM_TYPE_FUNCTION(ASM_WRAPPER_NAME(setjmp_bionic))51ASM_WRAPPER_NAME(setjmp_bionic):52 CFI_STARTPROC53 BTI_C54 mov x1, #155 b ASM_WRAPPER_NAME(sigsetjmp)56 CFI_ENDPROC57ASM_SIZE(ASM_WRAPPER_NAME(setjmp_bionic))58 59ASM_INTERCEPTOR_TRAMPOLINE(setjmp_bionic)60#endif61 62.global ASM_WRAPPER_NAME(sigsetjmp)63ASM_TYPE_FUNCTION(ASM_WRAPPER_NAME(sigsetjmp))64ASM_WRAPPER_NAME(sigsetjmp):65 CFI_STARTPROC66 BTI_C67 stp x19, x20, [x0, #0<<3]68 stp x21, x22, [x0, #2<<3]69 stp x23, x24, [x0, #4<<3]70 stp x25, x26, [x0, #6<<3]71 stp x27, x28, [x0, #8<<3]72 stp x29, x30, [x0, #10<<3]73 stp d8, d9, [x0, #14<<3]74 stp d10, d11, [x0, #16<<3]75 stp d12, d13, [x0, #18<<3]76 stp d14, d15, [x0, #20<<3]77 mov x2, sp78 str x2, [x0, #13<<3]79 // We always have the second argument to __sigjmp_save (savemask) set, since80 // the _setjmp function above has set it for us as `false`.81 // This function is defined in hwasan_interceptors.cc82 b __sigjmp_save83 CFI_ENDPROC84ASM_SIZE(ASM_WRAPPER_NAME(sigsetjmp))85 86ASM_INTERCEPTOR_TRAMPOLINE(sigsetjmp)87 88 89#if SANITIZER_ANDROID90ASM_TRAMPOLINE_ALIAS(sigsetjmp, sigsetjmp)91ASM_TRAMPOLINE_ALIAS(setjmp, setjmp_bionic)92#else93ASM_TRAMPOLINE_ALIAS(__sigsetjmp, sigsetjmp)94#endif95 96ASM_TRAMPOLINE_ALIAS(_setjmp, setjmp)97#endif98 99// We do not need executable stack.100NO_EXEC_STACK_DIRECTIVE101 102GNU_PROPERTY_BTI_PAC_GCS103