On 06/27/2013 10:37 AM, Peter Levart wrote:
> Hi,
>
> This version seems correct. Maybe just replace double volatile read at
> length re-check with a single one:
>
>
> private static BigInteger getRadixConversionCache(int radix, int
> exponent) {
> BigInteger[] cacheLine = powerCache[radix]; // volatile read
> if (exponent < cacheLine.length)
> return cacheLine[exponent];
>
> int oldLength = cacheLine.length;
> cacheLine = Arrays.copyOf(cacheLine, exponent + 1);
> for (int i = oldLength; i <= exponent; i++)
> cacheLine[i] = cacheLine[i - 1].pow(2);
>
> BigInteger[][] pc = powerCache; // volatile read again
> if (exponent >= pc[radix].length) {
> pc = pc.clone();
> pc[radix] = cacheLine;
> powerCache = pc; // volatile write, publish
> }
> return cacheLine[exponent];
> }
>
Yes, I'm voting for this one. All other improvements Peter had
suggested, while interesting, seem to not to worth the trouble.
-Aleksey.
