diff options
Diffstat (limited to 'sysdeps/alpha/ffs.S')
-rw-r--r-- | sysdeps/alpha/ffs.S | 67 |
1 files changed, 33 insertions, 34 deletions
diff --git a/sysdeps/alpha/ffs.S b/sysdeps/alpha/ffs.S index 959d1046d4..23dff6e06b 100644 --- a/sysdeps/alpha/ffs.S +++ b/sysdeps/alpha/ffs.S @@ -1,30 +1,29 @@ -/* Copyright (C) 1996 Free Software Foundation, Inc. +/* Copyright (C) 1996, 1997 Free Software Foundation, Inc. Contributed by David Mosberger (davidm@cs.arizona.edu). + This file is part of the GNU C Library. -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 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. -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. */ + 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., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ /* Finds the first bit set in an integer. Optimized for the Alpha -architecture. */ + architecture. */ #include <sysdep.h> - .set noreorder - .set noat + .set noreorder + .set noat ENTRY(ffs) #ifdef PROF @@ -38,36 +37,36 @@ ENTRY(ffs) ldq_u zero, 0(sp) # on the 21064, this helps dual-issuing addl a0, zero, a0 # the last insn and reduces the stall - negq a0, t0 # due to the srl instruction - and a0, t0, t0 + negq a0, t0 # due to the srl instruction + and a0, t0, t0 clr v0 beq a0, $done # now do binary search for first non-zero bit zapnot t0, 0x03, t2 - addq v0, 16, t3 - cmoveq t2, t3, v0 + addq v0, 16, t3 + cmoveq t2, t3, v0 zapnot t0, 0x05, t2 - addq v0, 8, t3 - cmoveq t2, t3, v0 + addq v0, 8, t3 + cmoveq t2, t3, v0 srl t0, v0, t0 addq v0, 1, v0 - and t0, 0x0f, t2 - addq v0, 4, t3 - cmoveq t2, t3, v0 + and t0, 0x0f, t2 + addq v0, 4, t3 + cmoveq t2, t3, v0 - and t0, 0x33, t2 - addq v0, 2, t3 - cmoveq t2, t3, v0 + and t0, 0x33, t2 + addq v0, 2, t3 + cmoveq t2, t3, v0 - and t0, 0x55, t2 - addq v0, 1, t3 - cmoveq t2, t3, v0 + and t0, 0x55, t2 + addq v0, 1, t3 + cmoveq t2, t3, v0 $done: ret - END(ffs) + END(ffs) |