/* * Copyright (c) 1993 Regents of the University of California. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the Computer Systems * Engineering Group at Lawrence Berkeley Laboratory. * 4. Neither the name of the University nor of the Laboratory may be used * to endorse or promote products derived from this software without * specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * LBL BSD kernel random number generator (used by statclock). * * Written by Steve McCanne & Chris Torek (mccanne@ee.lbl.gov, * torek@ee.lbl.gov), November, 1992. * * This implementation is based on ``Two Fast Implementations of * the "Minimal Standard" Random Number Generator", David G. Carta, * Communications of the ACM, Jan 1990, Vol 33 No 1. */ #ifdef sparc asm("\ .global _kernrand ;\ _kernrand: ;\ sethi %hi(16807), %o1 ;\ wr %o1, %lo(16807), %y ;\ set 0xffff, %o4 ;\ andcc %g0, 0, %o2 ;\ mulscc %o2, %o0, %o2 ;\ mulscc %o2, %o0, %o2 ;\ mulscc %o2, %o0, %o2 ;\ mulscc %o2, %o0, %o2 ;\ mulscc %o2, %o0, %o2 ;\ mulscc %o2, %o0, %o2 ;\ mulscc %o2, %o0, %o2 ;\ mulscc %o2, %o0, %o2 ;\ mulscc %o2, %o0, %o2 ;\ mulscc %o2, %o0, %o2 ;\ mulscc %o2, %o0, %o2 ;\ mulscc %o2, %o0, %o2 ;\ mulscc %o2, %o0, %o2 ;\ mulscc %o2, %o0, %o2 ;\ mulscc %o2, %o0, %o2 ;\ mulscc %o2, %g0, %o2 ;\ rd %y, %o3 ;\ srl %o2, 16, %o1 ;\ and %o4, %o2, %o0 ;\ sll %o0, 15, %o0 ;\ srl %o3, 17, %o3 ;\ or %o3, %o0, %o0 ;\ addcc %o0, %o1, %o0 ;\ bl 1f ;\ sethi %hi(0x7fffffff), %o1 ;\ retl ;\ nop ;\ 1: ;\ or %o1, %lo(0x7fffffff), %o1 ;\ add %o0, 1, %o0 ;\ retl ;\ and %o1, %o0, %o0 "); #else long kernrand(x) register long x; { register long hi, lo, t; hi = x / 127773; lo = x % 127773; t = 16807 * lo - 2836 * hi; if (t > 0) return (t); else return (t + 0x7fffffff); } #endif