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From Yonik Seeley <ysee...@gmail.com>
Subject Re: Lucene performance bottlenecks
Date Wed, 07 Dec 2005 15:43:22 GMT
> if (b>0) return b;
> Doing an 'and' of two bytes and checking if the result is 0 probably
> requires masking operations on >8 bit processors...

Sometimes you can get a peek into how a JVM would optimize things by
looking at the asm output of the code from a C compiler.
Both (b>=0) and ((b&0x80)!=0) generated the exact same asm in gcc:

        testb   %al, %al
        js      L4

-Yonik

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