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-rw-r--r--ports/sysdeps/alpha/strncpy.S87
1 files changed, 87 insertions, 0 deletions
diff --git a/ports/sysdeps/alpha/strncpy.S b/ports/sysdeps/alpha/strncpy.S
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+++ b/ports/sysdeps/alpha/strncpy.S
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+/* Copyright (C) 1996, 1997, 2003 Free Software Foundation, Inc.
+   Contributed by Richard Henderson (rth@tamu.edu)
+   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/>.  */
+
+/* Copy no more than COUNT bytes of the null-terminated string from
+   SRC to DST.  If SRC does not cover all of COUNT, the balance is
+   zeroed.  */
+
+#include <sysdep.h>
+
+	.set noat
+	.set noreorder
+
+	.text
+
+ENTRY(strncpy)
+	ldgp	gp, 0(pv)
+#ifdef PROF
+	lda	AT, _mcount
+	jsr	AT, (AT), _mcount
+#endif
+	.prologue 1
+
+	mov	a0, v0		# set return value now
+	beq	a2, $zerocount
+	jsr	t9, __stxncpy	# do the work of the copy
+
+	bne	a2, $multiword	# do we have full words left?
+
+	.align 3
+	subq	t8, 1, t2	# e0    : guess not
+	subq	t10, 1, t3	# .. e1 :
+	or	t2, t8, t2	# e0    : clear the bits between the last
+	or	t3, t10, t3	# .. e1 : written byte and the last byte in
+	andnot	t3, t2, t3	# e0    : COUNT
+	zap	t0, t3, t0	# e1    :
+	stq_u	t0, 0(a0)	# e0    :
+	ret			# .. e1 :
+
+$multiword:
+	subq	t8, 1, t7	# e0    : clear the final bits in the prev
+	or	t7, t8, t7	# e1    : word
+	zapnot	t0, t7, t0	# e0    :
+	subq	a2, 1, a2	# .. e1 :
+	stq_u	t0, 0(a0)	# e0    :
+	addq	a0, 8, a0	# .. e1 :
+
+	beq	a2, 1f		# e1    :
+	blbc	a2, 0f		# e1    :
+
+	stq_u	zero, 0(a0)	# e0    : zero one word
+	subq	a2, 1, a2	# .. e1 :
+	addq	a0, 8, a0	# e0    :
+	beq	a2, 1f		# .. e1 :
+
+0:	stq_u	zero, 0(a0)	# e0    : zero two words
+	subq	a2, 2, a2	# .. e1 :
+	stq_u	zero, 8(a0)	# e0    :
+	addq	a0, 16, a0	# .. e1 :
+	bne	a2, 0b		# e1    :
+	unop
+
+1:	ldq_u	t0, 0(a0)	# e0    : clear the leading bits in the final
+	subq	t10, 1, t7	# .. e1 : word
+	or	t7, t10, t7	# e0    :
+	zap	t0, t7, t0	# e1 (stall)
+	stq_u	t0, 0(a0)	# e0    :
+
+$zerocount:
+	ret			# .. e1 :
+
+	END(strncpy)
+libc_hidden_builtin_def (strncpy)