freebsd-skq/lib/libc/amd64/gen/rfork_thread.S
Peter Wemm 5d053f461c We've been lax about matching END() macros in asm code for some time. This
is used to set the ELF size attribute for functions.  It isn't normally
critical but some things can make use of it (gdb for stack traces).
Valgrind needs it so I'm adding it in.  The problem is present on all
branches and on both i386 and amd64.
2008-11-02 01:10:54 +00:00

103 lines
2.7 KiB
ArmAsm

/*-
* Copyright (c) 2000 Peter Wemm <peter@FreeBSD.org>
* Copyright (c) 2003 Alan L. Cox <alc@cs.rice.edu>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <machine/asm.h>
__FBSDID("$FreeBSD$");
/*
* With thanks to John Dyson for the original version of this.
*/
#include <SYS.h>
/*
* %edi %rsi %rdx %rcx
* rfork_thread(flags, stack_addr, start_fnc, start_arg);
*
* flags: Flags to rfork system call. See rfork(2).
* stack_addr: Top of stack for thread.
* start_fnc: Address of thread function to call in child.
* start_arg: Argument to pass to the thread function in child.
*/
ENTRY(rfork_thread)
pushq %rbx
pushq %r12
movq %rdx, %rbx
movq %rcx, %r12
/*
* Prepare and execute the thread creation syscall
*/
movq $SYS_rfork, %rax
KERNCALL
jb 2f
/*
* Check to see if we are in the parent or child
*/
cmpl $0, %edx
jnz 1f
popq %r12
popq %rbx
ret
/*
* If we are in the child (new thread), then
* set-up the call to the internal subroutine. If it
* returns, then call __exit.
*/
1:
movq %rsi, %rsp
movq %r12, %rdi
call *%rbx
movl %eax, %edi
/*
* Exit system call
*/
#ifdef SYS_exit
movq $SYS_exit, %rax
#else
movq $SYS_sys_exit, %rax
#endif
KERNCALL
/*
* Branch here if the thread creation fails:
*/
2:
popq %r12
popq %rbx
#ifdef PIC
movq PIC_GOT(HIDENAME(cerror)), %rdx
jmp *%rdx
#else
jmp HIDENAME(cerror)
#endif
END(rfork_thread)