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[help wanted] some questions

Open Heachy opened this issue 2 years ago • 1 comments

Hello, I have some questions about generating the logarithm table in your code.

In the generateLogTable function, why does the expression b = ((b - FIELD_SIZE) ^ polynomial); ensure that b is set to FIELD_SIZE different and non-repeating values? Looking forward to your explanation, thank you.

Heachy avatar Oct 19 '23 12:10 Heachy

Hello, I have some questions about the CodingLoop implementations you have written

Such as ByteInputOutputTableCodingLoop and InputOutputByteTableCodingLoop. In the case of the former, it uses byteCount as the outer loop, leading to the creation and destruction of too many temporary variables, ultimately resulting in slower execution speed compared to the latter. However, for OutputInputByteTableCodingLoop and InputOutputByteTableCodingLoop, even though the number of variable creations and destructions is similar, isn't it supposed to be fewer in the former? Why is it that the latter runs faster instead?

Here are my test results:

  • ByteInputOutputTableCodingLoop encodeParity: 163.9 MB/s
  • InputOutputByteTableCodingLoop encodeParity: 726.4 MB/s
  • OutputInputByteTableCodingLoop encodeParity: 477.1 MB/s

I hope to get some clarification from you.

Heachy avatar Oct 25 '23 11:10 Heachy