gem5/base/intmath.cc
Steve Reinhardt 0cdcb08d90 Change base/intmath.{cc,hh} to follow m5 style.
arch/alpha/alpha_tru64_process.cc:
base/intmath.hh:
base/statistics.cc:
base/str.cc:
cpu/o3/btb.cc:
sim/process.cc:
sim/syscall_emul.hh:
    Rename intmath.hh functions to follow m5 style
    (RoundUp -> roundUp, etc.).
base/intmath.cc:
    Rename intmath.hh functions to follow m5 style
    (RoundUp -> roundUp, etc.).
    Also reindent code in m5 style.

--HG--
extra : convert_revision : 57b853002bc3c9911e122599d9062b41a06d8e6a
2005-12-23 13:32:31 -05:00

59 lines
2.2 KiB
C++

/*
* Copyright (c) 2001, 2003-2005 The Regents of The University of Michigan
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* 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;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT
* OWNER 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.
*/
#include "base/intmath.hh"
int
prevPrime(int n)
{
int decr;
// If the number is even, let's start with the previous odd number.
if (!(n & 1))
--n;
// Lets test for divisibility by 3. Then we will be able to easily
// avoid numbers that are divisible by 3 in the future.
decr = n % 3;
if (decr == 0) {
n -= 2;
decr = 2;
}
else if (decr == 1)
decr = 4;
for (;;) {
if (isPrime(n))
return n;
n -= decr;
// Toggle between 2 and 4 to prevent trying numbers that are known
// to be divisible by 3.
decr = 6 - decr;
}
}