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Diffstat (limited to 'libc/sysdeps/linux/alpha/clone.S')
-rw-r--r-- | libc/sysdeps/linux/alpha/clone.S | 119 |
1 files changed, 119 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/alpha/clone.S b/libc/sysdeps/linux/alpha/clone.S new file mode 100644 index 000000000..b17a5ec68 --- /dev/null +++ b/libc/sysdeps/linux/alpha/clone.S @@ -0,0 +1,119 @@ +/* Copyright (C) 1996, 1997 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Richard Henderson <rth@tamu.edu>, 1996. + + 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. */ + +/* clone() is even more special than fork() as it mucks with stacks + and invokes a function in the right context after its all over. */ + +#include <features.h> +#define _ERRNO_H 1 +#include <bits/errno.h> + +/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg) */ + +#define a0 $16 +#define a1 $17 +#define a2 $18 +#define a3 $19 +#define v0 $0 +#define fp $15 +#define gp $29 +#define ra $26 +#define pv $27 +#define zero $31 + + .text +.globl __clone; +.align 3; +.ent __clone , 0; + +__clone: + .frame $30 , 0, $26 +#ifdef PROF + ldgp gp,0(pv) + .set noat + lda AT, _mcount + jsr AT, (AT), _mcount + .set at + .prologue 1 +#else + .prologue 0 +#endif + + /* Sanity check arguments. */ + ldiq v0,EINVAL + beq a0,$error /* no NULL function pointers */ + beq a1,$error /* no NULL stack pointers */ + + /* Save the fn ptr and arg on the new stack. */ + subq a1,16,a1 + stq a0,0(a1) + stq a3,8(a1) + + /* Do the system call */ + mov a2,a0 + ldiq v0,__NR_clone + call_pal 131 + + bne a3,$error + beq v0,thread_start + + /* Successful return from the parent */ + ret + + /* Something bad happened -- no child created */ +$error: +#ifndef PROF + br gp,1f +1: ldgp gp,0(gp) +#endif + jmp zero,__syscall_error + +.end __clone + +/* Load up the arguments to the function. Put this block of code in + its own function so that we can terminate the stack trace with our + debug info. */ + + .ent thread_start +thread_start: + .frame fp,0,zero,0 + mov zero,fp + .prologue 0 + + /* Load up the arguments. */ + ldq pv,0($30) + ldq a0,8($30) + addq $30,16,$30 + + /* Call the user's function */ + jsr ra,(pv) + ldgp gp,0(ra) + + /* Call _exit rather than doing it inline for breakpoint purposes */ + mov v0,a0 + jsr ra,_exit + + /* Die horribly. */ + halt + + .end thread_start + +.weak clone; + clone = __clone + |