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+/* Copyright (C) 1996 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 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., 675 Mass Ave,
+Cambridge, MA 02139, USA. */
+
+/* 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. Return the address of the terminating null in DEST, if
+ any, else DEST + COUNT. */
+
+#include <sysdep.h>
+
+ .set noat
+ .set noreorder
+
+ .text
+
+ENTRY(__stpncpy)
+ ldgp gp, 0(pv)
+ .prologue 1
+
+ beq a2, $zerocount
+ jsr t9, __stxncpy # do the work of the copy
+
+ and t8, 0xf0, t3 # binary search for byte offset of the
+ and t8, 0xcc, t2 # last byte written.
+ and t8, 0xaa, t1
+ andnot a0, 7, v0
+ cmovne t3, 4, t3
+ cmovne t2, 2, t2
+ cmovne t1, 1, t1
+ addq v0, t3, v0
+ addq t1, t2, t1
+ addq v0, t1, v0
+
+ bne a2, $multiword # do we have full words left?
+
+ .align 3
+ zapnot t0, t8, t4 # e0 : was last byte a null?
+ subq t8, 1, t2 # .. e1 :
+ addq v0, 1, t5 # e0 :
+ subq t10, 1, t3 # .. e1 :
+ or t2, t8, t2 # e0 : clear the bits between the last
+ or t3, t10, t3 # .. e1 : written byte and the last byte in
+ andnot t3, t2, t3 # e0 : COUNT
+ cmovne t4, t5, v0 # .. e1 : if last written wasnt null, inc v0
+ zap t0, t3, t0 # e0 :
+ stq_u t0, 0(a0) # e1 :
+ ret # .. e1 :
+
+ .align 3
+$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 :
+ ret # .. e1 :
+
+$zerocount:
+ mov a0, v0
+ ret
+
+ END(__stpncpy)
+
+weak_alias (__stpncpy, stpncpy)