add black-box
#980
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add black-box
#980
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The `black-box` function takes one argument and returns it, but optimization knows only that `black-box` returns a single value. This makes `black-box` useful for some testing and benchmarking tasks.
burgerrg
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Sep 22, 2025
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Thanks for this helpful procedure!
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Consider using much smaller loop sizes to keep the test time down.
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Thanks for looking it over! I worry about making the number of iterations too small to measure reliably. The current 1000 iterations is meant to provoke allocation on the order of a page, and the slowest variant takes sub-milliscond time on my machine.
burgerrg
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Since the tests take less than 1 ms, there's no need to risk doing less allocation.
jltaylor-us
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Sep 22, 2025
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The
black-boxfunction takes one argument and returns it, but optimization knows only thatblack-boxreturns a single value. This makesblack-boxuseful for some testing and benchmarking tasks.