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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. */
+
+/* Append no more than COUNT characters from the null-terminated string SRC
+ to the null-terminated string DST. Always null-terminate the new DST. */
+
+#include <sysdep.h>
+
+ .text
+
+ENTRY(strncat)
+ ldgp gp, 0(pv)
+ .prologue 1
+
+ mov a0, v0 # set up return value
+ beq a2, $zerocount
+
+ /* Find the end of the string. */
+
+ ldq_u t0, 0(a0) # load first quadword (a0 may be misaligned)
+ lda t1, -1(zero)
+ insqh t1, a0, t1
+ andnot a0, 7, a0
+ or t1, t0, t0
+ cmpbge zero, t0, t1 # t1 <- bitmask: bit i == 1 <==> i-th byte == 0
+ bne t1, $found
+
+$loop: ldq t0, 8(a0)
+ addq a0, 8, a0 # addr += 8
+ cmpbge zero, t0, t1
+ beq t1, $loop
+
+$found: negq t1, t2 # clear all but least set bit
+ and t1, t2, t1
+
+ and t1, 0xf0, t2 # binary search for that set bit
+ and t1, 0xcc, t3
+ and t1, 0xaa, t4
+ cmovne t2, 4, t2
+ cmovne t3, 2, t3
+ cmovne t4, 1, t4
+ addq t2, t3, t2
+ addq a0, t4, a0
+ addq a0, t2, a0
+
+ /* Now do the append. */
+
+ jsr t9, __stxncpy
+
+ /* Worry about the null termination. */
+
+ zapnot t0, t8, t1 # was last byte a null?
+ bne t1, 0f
+ ret
+
+0: and t10, 0x80, t1
+ bne t1, 1f
+
+ /* Here there are bytes left in the current word. Clear one. */
+ addq t10, t10, t10 # end-of-count bit <<= 1
+ zap t0, t10, t0
+ stq_u t0, 0(a0)
+ ret
+
+1: /* Here we must read the next DST word and clear the first byte. */
+ ldq_u t0, 8(a0)
+ zap t0, 1, t0
+ stq_u t0, 8(a0)
+
+$zerocount:
+ ret
+
+ END(strncat)