The following is a comparison between stdlib big integers (old) and the
specialized type (new) averaging 10 runs each:
name old time/op new time/op delta
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Square 418ns ± 0% 7ns ± 2% -98.39% (p=0.000 n=10+10)
name old allocs/op new allocs/op delta
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Square 1.00 ± 0% 0.00 -100.00% (p=0.000 n=10+10)
This is part of a series of commits to fully implement the uint256
package.