mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-14 17:11:06 +00:00
124 lines
3.6 KiB
ArmAsm
124 lines
3.6 KiB
ArmAsm
/* Save current context and install the given one.
|
|
Copyright (C) 2002, 2005 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
Contributed by Andreas Jaeger <aj@suse.de>, 2002.
|
|
|
|
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, write to the Free
|
|
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
|
|
02111-1307 USA. */
|
|
|
|
#include <sysdep.h>
|
|
|
|
#include "ucontext_i.h"
|
|
|
|
|
|
/* int __swapcontext (ucontext_t *oucp, const ucontext_t *ucp);
|
|
|
|
Saves the machine context in oucp such that when it is activated,
|
|
it appears as if __swapcontextt() returned again, restores the
|
|
machine context in ucp and thereby resumes execution in that
|
|
context.
|
|
|
|
This implementation is intended to be used for *synchronous* context
|
|
switches only. Therefore, it does not have to save anything
|
|
other than the PRESERVED state. */
|
|
|
|
ENTRY(__swapcontext)
|
|
/* Save the preserved registers, the registers used for passing args,
|
|
and the return address. */
|
|
movq %rbx, oRBX(%rdi)
|
|
movq %rbp, oRBP(%rdi)
|
|
movq %r12, oR12(%rdi)
|
|
movq %r13, oR13(%rdi)
|
|
movq %r14, oR14(%rdi)
|
|
movq %r15, oR15(%rdi)
|
|
|
|
movq %rdi, oRDI(%rdi)
|
|
movq %rsi, oRSI(%rdi)
|
|
movq %rdx, oRDX(%rdi)
|
|
movq %rcx, oRCX(%rdi)
|
|
movq %r8, oR8(%rdi)
|
|
movq %r9, oR9(%rdi)
|
|
|
|
movq (%rsp), %rcx
|
|
movq %rcx, oRIP(%rdi)
|
|
leaq 8(%rsp), %rcx /* Exclude the return address. */
|
|
movq %rcx, oRSP(%rdi)
|
|
|
|
/* We have separate floating-point register content memory on the
|
|
stack. We use the __fpregs_mem block in the context. Set the
|
|
links up correctly. */
|
|
leaq oFPREGSMEM(%rdi), %rcx
|
|
movq %rcx, oFPREGS(%rdi)
|
|
/* Save the floating-point environment. */
|
|
fnstenv (%rcx)
|
|
stmxcsr oMXCSR(%rdi)
|
|
|
|
|
|
/* The syscall destroys some registers, save them. */
|
|
movq %rsi, %r12
|
|
|
|
/* Save the current signal mask and install the new one with
|
|
rt_sigprocmask (SIG_BLOCK, newset, oldset,_NSIG/8). */
|
|
leaq oSIGMASK(%rdi), %rdx
|
|
leaq oSIGMASK(%rsi), %rsi
|
|
movl $SIG_SETMASK, %edi
|
|
movl $_NSIG8,%r10d
|
|
movl $__NR_rt_sigprocmask, %eax
|
|
syscall
|
|
cmpq $-4095, %rax /* Check %rax for error. */
|
|
jae SYSCALL_ERROR_LABEL /* Jump to error handler if error. */
|
|
|
|
/* Restore destroyed registers. */
|
|
movq %r12, %rsi
|
|
|
|
/* Restore the floating-point context. Not the registers, only the
|
|
rest. */
|
|
movq oFPREGS(%rsi), %rcx
|
|
fldenv (%rcx)
|
|
ldmxcsr oMXCSR(%rsi)
|
|
|
|
/* Load the new stack pointer and the preserved registers. */
|
|
movq oRSP(%rsi), %rsp
|
|
movq oRBX(%rsi), %rbx
|
|
movq oRBP(%rsi), %rbp
|
|
movq oR12(%rsi), %r12
|
|
movq oR13(%rsi), %r13
|
|
movq oR14(%rsi), %r14
|
|
movq oR15(%rsi), %r15
|
|
|
|
/* The following ret should return to the address set with
|
|
getcontext. Therefore push the address on the stack. */
|
|
movq oRIP(%rsi), %rcx
|
|
pushq %rcx
|
|
|
|
/* Setup registers used for passing args. */
|
|
movq oRDI(%rsi), %rdi
|
|
movq oRDX(%rsi), %rdx
|
|
movq oRCX(%rsi), %rcx
|
|
movq oR8(%rsi), %r8
|
|
movq oR9(%rsi), %r9
|
|
|
|
/* Setup finally %rsi. */
|
|
movq oRSI(%rsi), %rsi
|
|
|
|
/* Clear rax to indicate success. */
|
|
xorl %eax, %eax
|
|
|
|
L(pseudo_end):
|
|
ret
|
|
PSEUDO_END(__swapcontext)
|
|
|
|
weak_alias (__swapcontext, swapcontext)
|