Function core::arch::x86::_lzcnt_u32

pub unsafe fn _lzcnt_u32(x: u32) -> u32

This is supported on (non-crate feature miri-test-libstd or test or doctest) and x86 and target feature lzcnt only.

Counts the leading most significant zero bits.

When the operand is zero, it returns its size in bits.

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