libucontext/arch/x86_64/getcontext.S

49 lines
1.6 KiB
ArmAsm

/*
* Copyright (c) 2018, 2020 Ariadne Conill <ariadne@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.
*/
#include "defs.h"
ALIAS(getcontext, libucontext_getcontext)
FUNC(libucontext_getcontext)
/* copy all of the current registers into the ucontext structure */
movq %r8, REG_OFFSET(REG_R8)(%rdi)
movq %r9, REG_OFFSET(REG_R9)(%rdi)
movq %r10, REG_OFFSET(REG_R10)(%rdi)
movq %r11, REG_OFFSET(REG_R11)(%rdi)
movq %r12, REG_OFFSET(REG_R12)(%rdi)
movq %r13, REG_OFFSET(REG_R13)(%rdi)
movq %r14, REG_OFFSET(REG_R14)(%rdi)
movq %r15, REG_OFFSET(REG_R15)(%rdi)
movq %rdi, REG_OFFSET(REG_RDI)(%rdi)
movq %rsi, REG_OFFSET(REG_RSI)(%rdi)
movq %rbp, REG_OFFSET(REG_RBP)(%rdi)
movq %rbx, REG_OFFSET(REG_RBX)(%rdi)
movq %rdx, REG_OFFSET(REG_RDX)(%rdi)
movq %rax, REG_OFFSET(REG_RAX)(%rdi)
movq %rcx, REG_OFFSET(REG_RCX)(%rdi)
/* the first argument on the stack is the jump target (%rip), so we store it in the RIP
register in the ucontext structure. */
movq (%rsp), %rcx
movq %rcx, REG_OFFSET(REG_RIP)(%rdi)
/* finally take the stack pointer address (%rsp) offsetting by 8 to skip over the jump
target. */
leaq 8(%rsp), %rcx
movq %rcx, REG_OFFSET(REG_RSP)(%rdi)
/* we're all done here, return 0 */
xorl %eax, %eax
ret
END(libucontext_getcontext)