diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/ia64/clone2.S')
| -rw-r--r-- | sysdeps/unix/sysv/linux/ia64/clone2.S | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/ia64/clone2.S b/sysdeps/unix/sysv/linux/ia64/clone2.S new file mode 100644 index 0000000000..5c3e88a498 --- /dev/null +++ b/sysdeps/unix/sysv/linux/ia64/clone2.S @@ -0,0 +1,89 @@ +/* Copyright (C) 2000 Free Software Foundation, Inc. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + + +#include <sysdep.h> +#include <asm/errno.h> + + +/* int __clone2(int (*fn) (void *arg), void *child_stack_base, */ +/* size_t child_stack_size, int flags, void *arg) */ + +ENTRY(__clone2) + cmp.eq p6,p0=0,r32 + mov r8=EINVAL +(p6) br.cond.spnt.few __syscall_error + ;; + flushrs /* This is necessary, since the child */ + /* will be running with the same */ + /* register backing store for a few */ + /* instructions. We need to ensure */ + /* that it will not read or write the */ + /* backing store. */ + mov r17=ar.rsc /* save ar.rsc */ + mov r14=r32 /* save fn */ + mov r18=r33 /* save child_stack_base */ + /* Note that r15 is used to pass */ + /* syscall # to kernel & not preserved. */ + mov r16=r36 /* save arg */ + ;; + dep r36=0,r17,0,2 /* set to enforced lazy mode. */ + ;; + mov ar.rsc=r36 + cmp.ne p7,p0=0,r33 /* stack_base 0? */ + ;; +(p7) add r33=r33,r34 /* Stack base arg to syscall is */ + /* 0 if child_stack_base is 0, */ + /* child_stack_base + child_stack_size */ + /* otherwise. */ + /* The system call interface seems */ + /* quite contrived at this point. If */ + /* we don't pass the backing store */ + /* pointer, why do we pass the sp? */ + mov r32=r35 /* Flags are first syscall argument. */ + DO_CALL (SYS_ify (clone)) + cmp.eq p6,p0=-1,r10 + ;; +(p6) br.cond.spnt.few __syscall_error + +# define CHILD p6 +# define PARENT p7 + cmp.eq CHILD,PARENT=0,r8 /* Are we the child? */ + ;; +(CHILD) ld8 r34=[r14],8 /* Retrieve code pointer. */ +(CHILD) mov ar.bspstore=r18 /* Set register backing store in the child */ +(CHILD) mov r32=r16 /* Pass proper argument to fn */ + mov ar.rsc=r17 /* Restore RSE mode (both threads). */ +(PARENT) ret + ;; + ld8 gp=[r14] /* Load function gp. */ + mov b6=r34 + ;; + br.call.dptk.few rp=b6 /* Call fn(arg) in the child */ + ;; + mov r32=r8 /* Argument to _exit */ + .globl _exit + br.call.dpnt.few rp=_exit /* call _exit with result from fn. */ + ret /* Not reached. */ + +PSEUDO_END(__clone2) + +/* For now we leave __clone undefined. This is unlikely to be a */ +/* problem, since at least the i386 __clone in glibc always failed */ +/* with a 0 sp (eventhough the kernel explicitly handled it). */ +/* Thus all such calls needed to pass an explicit sp, and as a result, */ +/* would be unlikely to work on ia64. */ |