A smart compiler would have used the test (x & (x - 1)) == 0 to verify that x (a... | Hacker News

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		GeertB on June 10, 2024 \| parent \| context \| favorite \| on: Compilers are too smart A smart compiler would have used the test (x & (x - 1)) == 0 to verify that x (assumed non-zero) is a power of two. Don't know why Clang didn't do that here.

fooker on June 10, 2024 [–]

The tricky part is doing this without knowing the value of x!

This is why compilers have to rely on static analysis.

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