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+/* 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
+