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-rw-r--r--sysdeps/unix/sysv/linux/alpha/vfork.S57
1 files changed, 57 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/alpha/vfork.S b/sysdeps/unix/sysv/linux/alpha/vfork.S
new file mode 100644
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--- /dev/null
+++ b/sysdeps/unix/sysv/linux/alpha/vfork.S
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+/* Copyright (C) 2004-2014 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 <tcb-offsets.h>
+
+ENTRY(__vfork)
+	PSEUDO_PROLOGUE
+
+	/* Load the thread pointer value in A1 across the vfork.  */
+	rduniq
+	mov	v0, a1
+
+	/* Save the TCB-cached PID away in A2, and then negate the TCB
+           field.  But if it's zero, set it to 0x80000000 instead.  See
+           raise.c for the logic that relies on this value.  */
+	ldl	a2, PID_OFFSET(v0)
+	ldah	t0, -0x8000
+	negl	a2, t1
+	cmovne	a2, t1, t0
+	stl	t0, PID_OFFSET(v0);
+
+	lda	v0, SYS_ify(vfork)
+	call_pal PAL_callsys
+
+	/* Restore the original value of the TCB cache of the PID, if we're
+	   the parent.  But in the child (syscall return value equals zero),
+	   leave things as they are.  */
+	beq	v0, 1f
+	stl	a2, PID_OFFSET(a1)
+1:
+	/* Normal error check and return.  */
+	bne	a3, SYSCALL_ERROR_LABEL
+	ret
+
+PSEUDO_END (__vfork)
+libc_hidden_def (__vfork)
+
+weak_alias (__vfork, vfork)
+
+#if !NOT_IN_libc
+strong_alias (__vfork, __libc_vfork)
+#endif