153 lines
3.8 KiB
ArmAsm
153 lines
3.8 KiB
ArmAsm
/* Copyright (C) 1996-2016 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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Contributed by Ralf Baechle <ralf@linux-mips.org>, 1996.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library. If not, see
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<http://www.gnu.org/licenses/>. */
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/* clone() is even more special than fork() as it mucks with stacks
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and invokes a function in the right context after its all over. */
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#include <sys/asm.h>
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#include <sysdep.h>
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#define _ERRNO_H 1
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#include <bits/errno.h>
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#include <tls.h>
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#define CLONE_VM 0x00000100
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#define CLONE_THREAD 0x00010000
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/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg,
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void *parent_tidptr, void *tls, void *child_tidptr) */
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.text
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.set nomips16
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#if _MIPS_SIM == _ABIO32
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# define EXTRA_LOCALS 1
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#else
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# define EXTRA_LOCALS 0
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#endif
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LOCALSZ= 4
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FRAMESZ= (((NARGSAVE+LOCALSZ)*SZREG)+ALSZ)&ALMASK
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GPOFF= FRAMESZ-(1*SZREG)
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NESTED(__clone,4*SZREG,sp)
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#ifdef __PIC__
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SETUP_GP
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#endif
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PTR_SUBU sp, FRAMESZ
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cfi_adjust_cfa_offset (FRAMESZ)
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SETUP_GP64_STACK (GPOFF, __clone)
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#ifdef __PIC__
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SAVE_GP (GPOFF)
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#endif
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#ifdef PROF
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.set noat
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move $1,ra
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jal _mcount
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.set at
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#endif
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/* Sanity check arguments. */
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li v0,EINVAL
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beqz a0,L(error) /* No NULL function pointers. */
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beqz a1,L(error) /* No NULL stack pointers. */
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PTR_SUBU a1,32 /* Reserve argument save space. */
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PTR_S a0,0(a1) /* Save function pointer. */
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PTR_S a3,PTRSIZE(a1) /* Save argument pointer. */
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LONG_S a2,(PTRSIZE*2)(a1) /* Save clone flags. */
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move a0,a2
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/* Shuffle in the last three arguments - arguments 5, 6, and 7 to
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this function, but arguments 3, 4, and 5 to the syscall. */
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#if _MIPS_SIM == _ABIO32
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PTR_L a2,(FRAMESZ+PTRSIZE+PTRSIZE+16)(sp)
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PTR_S a2,16(sp)
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PTR_L a2,(FRAMESZ+16)(sp)
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PTR_L a3,(FRAMESZ+PTRSIZE+16)(sp)
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#else
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move a2,a4
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move a3,a5
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move a4,a6
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#endif
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/* Do the system call */
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li v0,__NR_clone
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cfi_endproc
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syscall
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bnez a3,L(error)
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beqz v0,L(thread_start)
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/* Successful return from the parent */
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cfi_startproc
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cfi_adjust_cfa_offset (FRAMESZ)
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SETUP_GP64_STACK_CFI (GPOFF)
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cfi_remember_state
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RESTORE_GP64_STACK
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PTR_ADDU sp, FRAMESZ
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cfi_adjust_cfa_offset (-FRAMESZ)
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ret
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/* Something bad happened -- no child created */
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L(error):
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cfi_restore_state
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#ifdef __PIC__
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PTR_LA t9,__syscall_error
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RESTORE_GP64_STACK
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PTR_ADDU sp, FRAMESZ
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cfi_adjust_cfa_offset (-FRAMESZ)
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jr t9
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#else
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RESTORE_GP64_STACK
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PTR_ADDU sp, FRAMESZ
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cfi_adjust_cfa_offset (-FRAMESZ)
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j __syscall_error
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#endif
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END(__clone)
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/* Load up the arguments to the function. Put this block of code in
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its own function so that we can terminate the stack trace with our
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debug info. */
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ENTRY(__thread_start)
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L(thread_start):
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cfi_undefined ($31)
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/* cp is already loaded. */
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SAVE_GP (GPOFF)
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/* The stackframe has been created on entry of clone(). */
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/* Restore the arg for user's function. */
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PTR_L t9,0(sp) /* Function pointer. */
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PTR_L a0,PTRSIZE(sp) /* Argument pointer. */
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/* Call the user's function. */
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jal t9
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/* Call _exit rather than doing it inline for breakpoint purposes. */
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move a0,v0
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#ifdef __PIC__
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PTR_LA t9,_exit
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jalr t9
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#else
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jal _exit
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#endif
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END(__thread_start)
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libc_hidden_def (__clone)
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weak_alias (__clone, clone)
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