forked from ariadne/libucontext
62 lines
1.8 KiB
ArmAsm
62 lines
1.8 KiB
ArmAsm
/*
|
|
* Copyright (c) 2018 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"
|
|
|
|
.globl __swapcontext;
|
|
__swapcontext:
|
|
str xzr, [x0, #R0_OFFSET + (0 * REGSZ)]
|
|
|
|
/* save GPRs */
|
|
stp x2, x3, [x0, #R0_OFFSET + (2 * REGSZ)]
|
|
stp x4, x5, [x0, #R0_OFFSET + (4 * REGSZ)]
|
|
stp x6, x7, [x0, #R0_OFFSET + (6 * REGSZ)]
|
|
stp x8, x9, [x0, #R0_OFFSET + (8 * REGSZ)]
|
|
stp x10, x11, [x0, #R0_OFFSET + (10 * REGSZ)]
|
|
stp x12, x13, [x0, #R0_OFFSET + (12 * REGSZ)]
|
|
stp x14, x15, [x0, #R0_OFFSET + (14 * REGSZ)]
|
|
stp x16, x17, [x0, #R0_OFFSET + (16 * REGSZ)]
|
|
stp x18, x19, [x0, #R0_OFFSET + (18 * REGSZ)]
|
|
stp x20, x21, [x0, #R0_OFFSET + (20 * REGSZ)]
|
|
stp x22, x23, [x0, #R0_OFFSET + (22 * REGSZ)]
|
|
stp x24, x25, [x0, #R0_OFFSET + (24 * REGSZ)]
|
|
stp x26, x27, [x0, #R0_OFFSET + (26 * REGSZ)]
|
|
stp x28, x29, [x0, #R0_OFFSET + (28 * REGSZ)]
|
|
str x30, [x0, #R0_OFFSET + (30 * REGSZ)]
|
|
|
|
/* save current program counter in link register */
|
|
str x30, [x0, #PC_OFFSET]
|
|
|
|
/* save current stack pointer */
|
|
mov x2, sp
|
|
str x2, [x0, #SP_OFFSET]
|
|
|
|
/* save pstate */
|
|
str xzr, [x0, #PSTATE_OFFSET]
|
|
|
|
/* context to swap to is in x1 so... we move to x0 and call setcontext */
|
|
/* store our link register in x28 */
|
|
mov x28, x30
|
|
|
|
/* move x1 to x0 and call setcontext */
|
|
mov x0, x1
|
|
bl __setcontext
|
|
|
|
/* hmm, we came back here try to return */
|
|
mov x30, x28
|
|
ret
|
|
|
|
|
|
|
|
.weak swapcontext;
|
|
swapcontext = __swapcontext;
|