1 /*
2  * SPDX-License-Identifier: BSD-3-Clause
3  * Copyright 2015 Intel Corporation.
4  * Copyright 2012 Hasan Alayli <[email protected]>
5  */
6 
7 #if defined(__x86_64__)
8 __asm__ (
9 ".text\n"
10 ".p2align 4,,15\n"
11 ".globl ctx_switch\n"
12 ".globl _ctx_switch\n"
13 "ctx_switch:\n"
14 "_ctx_switch:\n"
15 "	movq %rsp, 0(%rsi)	# save stack_pointer\n"
16 "	movq %rbp, 8(%rsi)	# save frame_pointer\n"
17 "	movq (%rsp), %rax	# save insn_pointer\n"
18 "	movq %rax, 16(%rsi)\n"
19 "	movq %rbx, 24(%rsi)\n	# save rbx,r12-r15\n"
20 "	movq 24(%rdi), %rbx\n"
21 "	movq %r15, 56(%rsi)\n"
22 "	movq %r14, 48(%rsi)\n"
23 "	movq 48(%rdi), %r14\n"
24 "	movq 56(%rdi), %r15\n"
25 "	movq %r13, 40(%rsi)\n"
26 "	movq %r12, 32(%rsi)\n"
27 "	movq 32(%rdi), %r12\n"
28 "	movq 40(%rdi), %r13\n"
29 "	movq 0(%rdi), %rsp	# restore stack_pointer\n"
30 "	movq 16(%rdi), %rax	# restore insn_pointer\n"
31 "	movq 8(%rdi), %rbp	# restore frame_pointer\n"
32 "	movq %rax, (%rsp)\n"
33 "	ret\n"
34 	);
35 #else
36 #pragma GCC error "__x86_64__ is not defined"
37 #endif
38