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/* Copyright (C) 2018 - 2022 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <sysdep.h>
#if defined(__XTENSA_CALL0_ABI__)
/*
* There's no entry instruction, makecontext sets up ucontext_t as if
* getcontext was called above and is about to return here.
* Registers on entry to this function:
* a12: func to call
* a13: ucp->uc_link, next context to activate if func returns
* a14: func argc
*/
.literal_position
ENTRY_PREFIX(__start_context)
beqz a14, 1f
/* load func arguments 0..1 from stack and free that space */
l32i a2, a1, 8
l32i a3, a1, 12
addi a1, a1, 16
bltui a14, 3, 1f
/* load func arguments 2..5 from stack and free that space */
l32i a4, a1, 0
l32i a5, a1, 4
l32i a6, a1, 8
l32i a7, a1, 12
addi a1, a1, 16
/* func arguments 6..argc - 1 are now at the top of the stack */
1:
callx0 a12
beqz a13, 1f
mov a2, a13
movi a4, JUMPTARGET (setcontext)
callx0 a4
1:
movi a4, JUMPTARGET (_exit)
movi a2, 0
callx0 a4
ill
END(__start_context)
#elif defined(__XTENSA_WINDOWED_ABI__)
/*
* There's no entry instruction, makecontext sets up ucontext_t as if
* getcontext was called above and is about to return here.
* Registers on entry to this function:
* a2: func to call
* a3: ucp->uc_link, next context to activate if func returns
* a4: func argc
* a5..a7: func arguments 0..2
*/
.literal_position
ENTRY_PREFIX(__start_context)
mov a10, a5
mov a11, a6
mov a12, a7
bltui a4, 4, 1f
/* load func arguments 3..5 from stack and free that space */
l32i a13, a1, 4
l32i a14, a1, 8
l32i a15, a1, 12
addi a5, a1, 16
movsp a1, a5
/* func arguments 6..argc - 1 are now at the top of the stack */
1:
callx8 a2
beqz a3, 1f
mov a6, a3
movi a4, JUMPTARGET (setcontext)
callx4 a4
1:
movi a4, JUMPTARGET (_exit)
movi a6, 0
callx4 a4
ill
END(__start_context)
#else
#error Unsupported Xtensa ABI
#endif
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