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Altera_Forum
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8 years ago

Arria DSP block merge with fixed point in OpenCL

Hello, I have been trying to implement fixed point algorithms using opencl for an arria10. I am interested in this approach because I run out of DSP blocks when I used floating point so I fig...
Altera_Forum's avatar
Altera_Forum
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8 years ago

It is likely that Altera's OpenCL compiler has not been equipped with the capability to perform fixed-point multiplication in 18 × 18 Full Mode yet, or maybe it is not correctly seeing your variables as fixed-point. Which version of Quartus/AOC are you using? I noticed that v16.1 acts much more intelligently when it comes to DSP packing, compared to previous versions. If you are using an older version, I recommend trying v16.1.2. The HTML report in this version will explicitly mention what type of operation is being performed by each DSP.