sh: add first attempt at a getcontext implementation

master
Ariadne Conill 2020-12-11 21:58:56 +00:00
parent 2692ecf74a
commit fd06f42bc3
1 changed files with 52 additions and 0 deletions

52
arch/sh/getcontext.S Normal file
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/*
* Copyright (c) 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)
mov #0, r0 /* zero out r0, not preserved per ABI */
mov.l r0, @(REG_OFFSET(0), r4) /* save GPRs r0-r15 */
mov.l r1, @(REG_OFFSET(1), r4)
mov.l r2, @(REG_OFFSET(2), r4)
mov.l r3, @(REG_OFFSET(3), r4)
mov.l r4, @(REG_OFFSET(4), r4)
mov.l r5, @(REG_OFFSET(5), r4)
mov.l r6, @(REG_OFFSET(6), r4)
mov.l r7, @(REG_OFFSET(7), r4)
mov.l r8, @(REG_OFFSET(8), r4)
mov.l r9, @(REG_OFFSET(9), r4)
mov.l r10, @(REG_OFFSET(10), r4)
mov.l r11, @(REG_OFFSET(11), r4)
mov.l r12, @(REG_OFFSET(12), r4)
mov.l r13, @(REG_OFFSET(13), r4)
mov.l r14, @(REG_OFFSET(14), r4)
mov.l r15, @(REG_OFFSET(15), r4)
mov r4, r0 /* move r4 to r0, and increment by REG_OFFSET(REG_MACL) + REG_SZ. */
add #(REG_OFFSET(REG_MACL + 1)), r0
sts.l macl, @-r0 /* save macl/mach registers */
sts.l mach, @-r0
stc.l gbr, @-r0 /* save gbr register */
movt r1 /* load T-flag into r1 */
mov.l r1, @-r0 /* save T-flag as SR register */
sts.l pr, @-r0 /* save current PR */
sts.l pr, @-r0 /* save current PR as PC as well */
mov #0, r0
END(libucontext_getcontext)