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diff --git a/base/intmath.cc b/base/intmath.cc
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-/*
- * 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;
- }
-}