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authorJoseph Myers <joseph@codesourcery.com>2012-07-01 13:08:59 +0000
committerJoseph Myers <joseph@codesourcery.com>2012-07-01 13:08:59 +0000
commite84eabb3871c9b39e59323bf3f6b98c2ca9d1cd0 (patch)
treedff3f1b79454b518d15a7b9bbedeb57ff156bbe8 /ports/sysdeps/alpha/strncat.S
parent75f0d3040a2c2de8842bfa7a09e11da1a73e17d0 (diff)
parente64ac02c24b43659048622714afdc92fedf561fa (diff)
Merge glibc-ports into ports/ directory.glibc-2.16-ports-merge
Diffstat (limited to 'ports/sysdeps/alpha/strncat.S')
-rw-r--r--ports/sysdeps/alpha/strncat.S94
1 files changed, 94 insertions, 0 deletions
diff --git a/ports/sysdeps/alpha/strncat.S b/ports/sysdeps/alpha/strncat.S
new file mode 100644
index 0000000000..832a3ed506
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+++ b/ports/sysdeps/alpha/strncat.S
@@ -0,0 +1,94 @@
+/* Copyright (C) 1996 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Richard Henderson <rth@tamu.edu>, 1996.
+
+ 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/>. */
+
+/* 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)
+#ifdef PROF
+ .set noat
+ lda AT, _mcount
+ jsr AT, (AT), _mcount
+ .set at
+#endif
+ .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)