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MMX Multiplying of 3 values on 16bits

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Guest_imported

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Jan 1, 1970
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I stored in a MMX registry 4 copies of a 16 bits signed number : u u u u (mm0)
In another one I put another number : v v v v (mm1)
Finally i have 4 16bits numbers stored in mm3 :
a r g b
Well ... I need to obtain on 64 bits this result :
a*u*v r*u*v g*u*v b*u*v
I use actually 3 pmulh but losses are too important... Just a piece of advise limits on a r g and b are :

0<= a <= 0x0100
0<= r <= 0x00FF
0<= g <= 0x00FF
0<= b <= 0x00FF

So if you found any good lossless and FAST techniques. Please send me a mail It should be great... ;)
Thanks.


 
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