You could check if the middle 64-12-12 bits are all 1's, and if they are branch ... | Hacker News

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		londons_explore on May 29, 2020 \| parent \| context \| favorite \| on: The radix 2^51 trick (2017) You could check if the middle 64-12-12 bits are all 1's, and if they are branch to a slow codepath. It would be an incredibly rare case, so branch prediction will always get it right, and the cost of a branch nearly nill.

a1369209993 on May 29, 2020 [–]

If you're trying to add two 256-bit numbers, there's probably cryptography involved, and data-dependant branches are poison to crypto code.

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