Many CPUs have ways of counting leading zeroes. In gcc, these can be access using __builtin_clz, __builtin_clzl and __builtin_clzll.

So you could use Inline::C to run C code that uses that.

Or you could use XS or FFI::Platypus to access a C library that provides a function that uses that.

In reply to Re: Most Significant Set Bit by ikegami
in thread Most Significant Set Bit by coldr3ality

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