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A comment on Six times faster than C. Parent comment

Re:Six times faster than C by fuber2018 on Friday July 07, 2023 @06:10AM (#36629583)
If I unroll the main while loop to handle 4x as much each time through the loop in the SWAR-version, the runtime drops to 0.0562s (average 10 runs).

That's an overall 57.5x speedup.

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Re:Six times faster than C by fuber2018 on Friday July 07, 2023 @07:13AM (#36630014)
If I convert the unrolled-64-bit SWAR function to use 32-bit chunks instead, average runtime almost doubles, approx. 0.1s now.

Need sleep now.

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Re:Six times faster than C by fuber2018 on Friday July 07, 2023 @07:35AM (#36630162)
If I unroll the 64-bit SWAR version by 8x instead of 4x, the runtime is reduced by another 10% over the 4x-unrolled SWAR version. Diminishing returns...
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