1/*
2 * Copyright (c) 2015 Travis Geiselbrecht
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining
5 * a copy of this software and associated documentation files
6 * (the "Software"), to deal in the Software without restriction,
7 * including without limitation the rights to use, copy, modify, merge,
8 * publish, distribute, sublicense, and/or sell copies of the Software,
9 * and to permit persons to whom the Software is furnished to do so,
10 * subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be
13 * included in all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
18 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
19 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
20 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
21 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
22 */
23#include <asm.h>
24
25/* void x86_64_context_switch(uint64_t *oldsp, uint64_t newsp) */
26FUNCTION(x86_64_context_switch)
27    /* save the old context and restore the new */
28    pushf
29    pushq %rbx
30    pushq %rbp
31    pushq %r12
32    pushq %r13
33    pushq %r14
34    pushq %r15
35
36    movq %rsp,(%rdi)
37    movq %rsi,%rsp
38
39    popq %r15
40    popq %r14
41    popq %r13
42    popq %r12
43    popq %rbp
44    popq %rbx
45    popf
46
47    retq
48
49