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Altera_Forum
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15 years ago

NIOS2 HW & DIV Instructions + FPU

Hello i am in charge of designing a system that does a lot of complex sin/cos/* instructions and i need them to be fast. I am using NIOS2-F at 100mhz in a Cyclone IV. I've enabled HW and DIV ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

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If you are seeing those 'custom' opcodes without a custom instruction then I would think you are having the wrong code linked in. It could be that code is being linked in but never executed but that would surprise me.

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Yes that IS really weird because i am not using the custom instruction IP at QSys.

However if i dont use the compiler flags my code runs 70~80% slower.