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-rw-r--r--sysdeps/unix/sysv/linux/ia64/clone2.S105
1 files changed, 105 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..61980187e2
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/ia64/clone2.S
@@ -0,0 +1,105 @@
+/* Copyright (C) 2000-2014 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   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, see
+   <http://www.gnu.org/licenses/>.  */
+
+
+#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,		*/
+/*	         pid_t *parent_tid, void *tls, pid_t *child_tid)	*/
+
+#define CHILD	p8
+#define PARENT	p9
+
+ENTRY(__clone2)
+	.prologue
+	alloc r2=ar.pfs,8,1,6,0
+	cmp.eq p6,p0=0,in0
+	cmp.eq p7,p0=0,in1
+	mov r8=EINVAL
+	mov out0=in3		/* Flags are first syscall argument.	*/
+	mov out1=in1		/* Stack address.			*/
+(p6)	br.cond.spnt.many __syscall_error	/* no NULL function pointers */
+(p7)	br.cond.spnt.many __syscall_error	/* no NULL stack pointers */
+	;;
+	mov out2=in2		/* Stack size.				*/
+	mov out3=in5		/* Parent TID Pointer			*/
+	mov out4=in7		/* Child TID Pointer			*/
+	mov out5=in6		/* TLS pointer				*/
+	/*
+	 * clone2() is special: the child cannot execute br.ret right
+	 * after the system call returns, because it starts out
+	 * executing on an empty stack.  Because of this, we can't use
+	 * the new (lightweight) syscall convention here.  Instead, we
+	 * just fall back on always using "break".
+	 *
+	 * Furthermore, since the child starts with an empty stack, we
+	 * need to avoid unwinding past invalid memory.  To that end,
+	 * we'll pretend now that __clone2() is the end of the
+	 * call-chain.  This is wrong for the parent, but only until
+	 * it returns from clone2() but it's better than the
+	 * alternative.
+	 */
+	mov r15=SYS_ify (clone2)
+	.save rp, r0
+	break __BREAK_SYSCALL
+	.body
+	cmp.eq p6,p0=-1,r10
+	cmp.eq CHILD,PARENT=0,r8 /* Are we the child?   */
+(p6)	br.cond.spnt.many __syscall_error
+	;;
+(CHILD)	mov loc0=gp
+(PARENT) ret
+	;;
+#ifdef RESET_PID
+	tbit.nz p6,p0=in3,16	/* CLONE_THREAD */
+	tbit.z p7,p10=in3,8	/* CLONE_VM */
+(p6)	br.cond.dptk 1f
+	;;
+	mov r15=SYS_ify (getpid)
+(p10)	addl r8=-1,r0
+(p7)	break __BREAK_SYSCALL
+	;;
+	add r9=PID,r13
+	add r10=TID,r13
+	;;
+	st4 [r9]=r8
+	st4 [r10]=r8
+	;;
+#endif
+1:	ld8 out1=[in0],8	/* Retrieve code pointer.	*/
+	mov out0=in4		/* Pass proper argument	to fn */
+	;;
+	ld8 gp=[in0]		/* Load function gp.		*/
+	mov b6=out1
+	br.call.dptk.many rp=b6	/* Call fn(arg) in the child 	*/
+	;;
+	mov out0=r8		/* Argument to _exit		*/
+	mov gp=loc0
+	.globl HIDDEN_JUMPTARGET(_exit)
+	br.call.dpnt.many rp=HIDDEN_JUMPTARGET(_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.					*/