mpir/mpn/x86/p6/divexact_by3c.asm

37 lines
1.4 KiB
NASM

dnl Intel P6 mpn_divexact_by3 -- mpn division by 3, expecting no remainder.
dnl Copyright 2000, 2002 Free Software Foundation, Inc.
dnl
dnl This file is part of the GNU MP Library.
dnl
dnl The GNU MP Library is free software; you can redistribute it and/or
dnl modify it under the terms of the GNU Lesser General Public License as
dnl published by the Free Software Foundation; either version 2.1 of the
dnl License, or (at your option) any later version.
dnl
dnl The GNU MP Library is distributed in the hope that it will be useful,
dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
dnl Lesser General Public License for more details.
dnl
dnl You should have received a copy of the GNU Lesser General Public
dnl License along with the GNU MP Library; see the file COPYING.LIB. If
dnl not, write to the Free Software Foundation, Inc., 51 Franklin Street,
dnl Fifth Floor, Boston, MA 02110-1301, USA.
include(`../config.m4')
C P6: 8.5 cycles/limb
C The P5 code runs well on P6, in fact better than anything else found so
C far. An imul is 4 cycles, meaning the two cmp/sbbl pairs on the dependent
C path are taking 4.5 cycles.
C
C The destination cache line prefetching is unnecessary on P6, but removing
C it is a 2 cycle slowdown (approx), so it must be inducing something good
C in the out of order execution.
include_mpn(`x86/pentium/divexact_by3c.asm')