A place for talking about the Ethereum Virtual Machine on Farcaster.

is there a “magic number” solution to flipping a (uint32) number’s endianness? or is masking and shifting each byte always the best way?

cc @optimizoor

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professional @slokh and @0xalexander fanboy

Very good question. I just recalled I had this problem I’ve yet to solve.

According to Hacker's Delight, it doesn't look like there's an arithmetic solution. It proposes using a rotating shift that we can emulate in the EVM by first duplicating the number to 64 bytes using MUL. This should be better than masking and shifting each byte separately. In principle this should cost 41 gas.

oooh this looks promising, lemme see what the opcodes work out to