gcc/libsanitizer/hwasan/hwasan_setjmp.S
Martin Liska 1ee3d1ef10 libsanitizer: add hwasan.
Introduce the libhwasan library from LLVM sources.
2020-11-25 16:35:30 +00:00

101 lines
2.8 KiB
ArmAsm

//===-- hwasan_setjmp.S --------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file is a part of HWAddressSanitizer.
//
// HWAddressSanitizer runtime.
//===----------------------------------------------------------------------===//
#include "sanitizer_common/sanitizer_asm.h"
#if HWASAN_WITH_INTERCEPTORS && defined(__aarch64__)
#include "sanitizer_common/sanitizer_platform.h"
// We want to save the context of the calling function.
// That requires
// 1) No modification of the link register by this function.
// 2) No modification of the stack pointer by this function.
// 3) (no modification of any other saved register, but that's not really going
// to occur, and hence isn't as much of a worry).
//
// There's essentially no way to ensure that the compiler will not modify the
// stack pointer when compiling a C function.
// Hence we have to write this function in assembly.
.section .text
.file "hwasan_setjmp.S"
.global __interceptor_setjmp
ASM_TYPE_FUNCTION(__interceptor_setjmp)
__interceptor_setjmp:
CFI_STARTPROC
mov x1, #0
b __interceptor_sigsetjmp
CFI_ENDPROC
ASM_SIZE(__interceptor_setjmp)
#if SANITIZER_ANDROID
// Bionic also defines a function `setjmp` that calls `sigsetjmp` saving the
// current signal.
.global __interceptor_setjmp_bionic
ASM_TYPE_FUNCTION(__interceptor_setjmp_bionic)
__interceptor_setjmp_bionic:
CFI_STARTPROC
mov x1, #1
b __interceptor_sigsetjmp
CFI_ENDPROC
ASM_SIZE(__interceptor_setjmp_bionic)
#endif
.global __interceptor_sigsetjmp
ASM_TYPE_FUNCTION(__interceptor_sigsetjmp)
__interceptor_sigsetjmp:
CFI_STARTPROC
stp x19, x20, [x0, #0<<3]
stp x21, x22, [x0, #2<<3]
stp x23, x24, [x0, #4<<3]
stp x25, x26, [x0, #6<<3]
stp x27, x28, [x0, #8<<3]
stp x29, x30, [x0, #10<<3]
stp d8, d9, [x0, #14<<3]
stp d10, d11, [x0, #16<<3]
stp d12, d13, [x0, #18<<3]
stp d14, d15, [x0, #20<<3]
mov x2, sp
str x2, [x0, #13<<3]
// We always have the second argument to __sigjmp_save (savemask) set, since
// the _setjmp function above has set it for us as `false`.
// This function is defined in hwasan_interceptors.cc
b __sigjmp_save
CFI_ENDPROC
ASM_SIZE(__interceptor_sigsetjmp)
.macro ALIAS first second
.globl \second
.equ \second\(), \first
.endm
#if SANITIZER_ANDROID
ALIAS __interceptor_sigsetjmp, sigsetjmp
.weak sigsetjmp
ALIAS __interceptor_setjmp_bionic, setjmp
.weak setjmp
#else
ALIAS __interceptor_sigsetjmp, __sigsetjmp
.weak __sigsetjmp
#endif
ALIAS __interceptor_setjmp, _setjmp
.weak _setjmp
#endif
// We do not need executable stack.
NO_EXEC_STACK_DIRECTIVE