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Diffstat (limited to 'sysdeps/alpha/strlen.S')
-rw-r--r-- | sysdeps/alpha/strlen.S | 76 |
1 files changed, 0 insertions, 76 deletions
diff --git a/sysdeps/alpha/strlen.S b/sysdeps/alpha/strlen.S deleted file mode 100644 index 72aef91e0e..0000000000 --- a/sysdeps/alpha/strlen.S +++ /dev/null @@ -1,76 +0,0 @@ -/* Copyright (C) 1996-2017 Free Software Foundation, Inc. - Contributed by David Mosberger (davidm@cs.arizona.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/>. */ - -/* Finds length of a 0-terminated string. Optimized for the Alpha - architecture: - - - memory accessed as aligned quadwords only - - uses cmpbge to compare 8 bytes in parallel - - does binary search to find 0 byte in last quadword (HAKMEM - needed 12 instructions to do this instead of the 8 instructions - that the binary search needs). -*/ - -#include <sysdep.h> - - .set noreorder - .set noat - -ENTRY(strlen) -#ifdef PROF - ldgp gp, 0(pv) - lda AT, _mcount - jsr AT, (AT), _mcount - .prologue 1 -#else - .prologue 0 -#endif - - ldq_u t0, 0(a0) # load first quadword (a0 may be misaligned) - lda t1, -1(zero) - insqh t1, a0, t1 - andnot a0, 7, v0 - or t1, t0, t0 - nop # dual issue the next two on ev5 - cmpbge zero, t0, t1 # t1 <- bitmask: bit i == 1 <==> i-th byte == 0 - bne t1, $found - -$loop: ldq t0, 8(v0) - addq v0, 8, v0 # 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 v0, t4, v0 - addq v0, t2, v0 - nop # dual issue next two on ev4 and ev5 - - subq v0, a0, v0 - ret - - END(strlen) -libc_hidden_builtin_def (strlen) |