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Re: [autovect] [patch] vectorize reduction without specialized target support


On Wed, Jun 15, 2005 at 11:05:54PM +0300, Dorit Naishlos wrote:
> This scheme requires adding new tree-codes for the vector-shifts. I
> introduced the simplest vector-shift possible - the shift amount is in
> bytes, and is a constant (immediate value). This has to potential to be
> easily expanded to the most efficient code, and be applicable to as many
> targets as possible.

One change I'd prefer is that the shift count remain in bits, as with
any other shift that gcc supports.  I think that's less confusing.

(Despite the fact that both SSE and Altivec actually implement that
shift by encoding the number of bytes into the instruction.)


r~


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