1 /* Copyright (C) 1996, 1997 Free Software Foundation, Inc.
2 Contributed by David Mosberger (davidm@cs.arizona.edu).
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Library General Public License as
7 published by the Free Software Foundation; either version 2 of the
8 License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Library General Public License for more details.
15 You should have received a copy of the GNU Library General Public
16 License along with the GNU C Library; see the file COPYING.LIB. If not,
17 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA. */
20 /* Finds the first bit set in an integer. Optimized for the Alpha
38 ldq_u zero, 0(sp) # on the 21064, this helps dual-issuing
39 addl a0, zero, a0 # the last insn and reduces the stall
40 negq a0, t0 # due to the srl instruction
45 # now do binary search for first non-zero bit