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/* Copyright (C) 2012-2021 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
<https://www.gnu.org/licenses/>. */
/* ??? Needs more rearrangement for the LDM to handle thumb mode. */
#define NO_THUMB
#include <sysdep.h>
#include <rtld-global-offsets.h>
#include "ucontext_i.h"
.syntax unified
.text
/* int setcontext (const ucontext_t *ucp) */
ENTRY(__setcontext)
mov r4, r0
add r0, r0, #UCONTEXT_REGSPACE
/* Restore the VFP registers. Copied from arm/__longjmp.S. */
#ifdef SHARED
ldr r2, 1f
ldr r1, .Lrtld_global_ro
0: add r2, pc, r2
ldr r2, [r2, r1]
ldr r2, [r2, #RTLD_GLOBAL_RO_DL_HWCAP_OFFSET]
#else
ldr r2, .Lhwcap
ldr r2, [r2, #0]
#endif
#ifdef __SOFTFP__
tst r2, #HWCAP_ARM_VFP
beq .Lno_vfp_sc
#endif
/* Following instruction is vldmia r0!, {d8-d15}. */
ldc p11, cr8, [r0], #64
/* Restore the floating-point status register. */
ldr r1, [r0], #4
/* Following instruction is fmxr fpscr, r1. */
mcr p10, 7, r1, cr1, cr0, 0
.Lno_vfp_sc:
tst r2, #HWCAP_ARM_IWMMXT
beq .Lno_iwmmxt_sc
/* Restore the call-preserved iWMMXt registers. */
/* Following instructions are wldrd wr10, [r0], #8 (etc.) */
ldcl p1, cr10, [r0], #8
ldcl p1, cr11, [r0], #8
ldcl p1, cr12, [r0], #8
ldcl p1, cr13, [r0], #8
ldcl p1, cr14, [r0], #8
ldcl p1, cr15, [r0], #8
.Lno_iwmmxt_sc:
/* Now bring back the signal status. */
mov r0, #SIG_SETMASK
add r1, r4, #UCONTEXT_SIGMASK
mov r2, #0
bl PLTJMP(__sigprocmask)
/* Loading r0-r3 makes makecontext easier. */
add r14, r4, #MCONTEXT_ARM_R0
ldmia r14, {r0-r12}
ldr r13, [r14, #(MCONTEXT_ARM_SP - MCONTEXT_ARM_R0)]
add r14, r14, #(MCONTEXT_ARM_LR - MCONTEXT_ARM_R0)
ldmia r14, {r14, pc}
END(setcontext)
weak_alias(__setcontext, setcontext)
/* Called when a makecontext() context returns. Start the
context in R4 or fall through to exit(). */
/* Unwind descriptors are looked up based on PC - 2, so we have to
make sure to mark the instruction preceding the __startcontext
label as .cantunwind. */
.fnstart
.cantunwind
nop
ENTRY(__startcontext)
movs r0, r4
bne PLTJMP(__setcontext)
@ New context was 0 - exit
b PLTJMP(HIDDEN_JUMPTARGET(exit))
.fnend
END(__startcontext)
#ifdef SHARED
1: .long _GLOBAL_OFFSET_TABLE_ - 0b - PC_OFS
.Lrtld_global_ro:
.long C_SYMBOL_NAME(_rtld_global_ro)(GOT)
#else
.Lhwcap:
.long C_SYMBOL_NAME(_dl_hwcap)
#endif
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