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Re: RFC: using clz for comparing to zero on the tree level.
On Fri, May 09, 2003 at 03:12:20AM +0100, Olly Betts wrote:
> This isn't directly relevant to the clz issue, but I notice that the
> above sequence isn't optimal for any ARM - this is better:
>
> rsbs out, in, #1
> movcc out, #0
>
> This is essentially: out = 1 - in; if ((unsigned)in > 1) out = 0;
Actually, it is relevant. It brings us back down to one
target for which the clz transformation is profitable.
r~