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PGorl1's avatar
PGorl1
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6 years ago

[FPGA SDK for OpenCL] External IO channel problem.

System integrator fails when the data type size of the external IO channel is different from 256b. You can reproduce the error using the attached code. $ make trigger_bug aoc -v -v -v -D__TRIGGER...
PGorl1's avatar
PGorl1
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6 years ago
posted a file.
HRZ's avatar
HRZ
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6 years ago

>If I'm forced to process 256b, the occurring 'Stall%' will propagate along the pipeline and will effects the other computations/memory accesses.

This is a perfectly valid point to explain why "padding" the data to match the physical width is not a good idea. You will be essentially limiting your kernel "throughput" to the throughput of the I/O channel, even if you don't need to fully utilize the channel throughput.