libucontext/arch/x86_64/setcontext.S

45 lines
1.2 KiB
ArmAsm

/*
* Copyright (c) 2018 William Pitcock <nenolod@dereferenced.org>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* This software is provided 'as is' and without any warranty, express or
* implied. In no event shall the authors be liable for any damages arising
* from the use of this software.
*/
.globl __setcontext;
__setcontext:
/* set all of the registers */
movq 40(%rdi), %r8
movq 48(%rdi), %r9
movq 56(%rdi), %r10
movq 64(%rdi), %r11
movq 72(%rdi), %r12
movq 80(%rdi), %r13
movq 88(%rdi), %r14
movq 96(%rdi), %r15
movq 112(%rdi), %rbp
movq 120(%rdi), %rsi
movq 128(%rdi), %rbx
movq 136(%rdi), %rdx
movq 144(%rdi), %rax
movq 152(%rdi), %rcx
movq 160(%rdi), %rsp
/* set the jump target by pushing it to the stack.
ret will pop the new %rip from the stack, causing us to jump there. */
pushq 168(%rdi)
/* finally, set %rdi correctly. */
movq 104(%rdi), %rdi
/* we're all done here, return 0 */
xorl %eax, %eax
ret
.weak setcontext;
setcontext = __setcontext;