[tremor] A possible improvement for some of the processor where tables hit hard

[Monty]

On Sun, Oct 13, 2002 at 04:01:56PM -0400, marc dukette wrote:
> I have replaced the mask table in bitwise.c with the following, and while it
> has little to no effect on an SA processor it does appear to help the
> version we have running on MIPS, so it may be of value to other processors
> as well:
> 
> old:
>   unsigned long m= mask[bits];
> 
> new:
>   unsigned long m= (((unsigned int)-1)>>(32-bits));
> 
> and of course you can now remove the mask table.  I'm just throwing this
> out, not sure if it's worth adding to the standard or not.

Good basic idea, but not equivalent.  In the case where bits==0...

Monty
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