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DSPIC 64-bit Floating Point

 
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oxo



Joined: 13 Nov 2012
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DSPIC 64-bit Floating Point
PostPosted: Thu Oct 12, 2017 3:42 am     Reply with quote

Hi all,

Does anyone have timing comparisons for 32 vs 64 bit floating point on DSPIC?

(yeah, I know I could try it myself, but this may be quicker)
Ttelmah



Joined: 11 Mar 2010
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PostPosted: Fri Oct 13, 2017 4:01 am     Reply with quote

They generally take about 2.5* the time.
A * is slightly less than double (about 190 versus 110 instructions to load two variables, multiply and save the result). Division was about 530 to 190. sin about 8500 versus 3200.
So the multiply is the fastest (<2*) and the others get up to about 2.8*.

These are 'rough figures' I noted in a file when I looked into this....
oxo



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PostPosted: Mon Oct 23, 2017 12:55 am     Reply with quote

Thanks very muchly.
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