bitintr 0.1.0

Portable Bit Manipulation Intrinsics.
Documentation 
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use int::IntF32T64;
use alg;

mod intrinsics {
    use int::IntF32T64;
    use std::mem::size_of;

    #[allow(dead_code)]
    extern "platform-intrinsic" {
        fn x86_bmi_bextr_32(x: u32, y: u32) -> u32;
        fn x86_bmi_bextr_64(x: u64, y: u64) -> u64;
    }


    pub unsafe fn bextri<T: IntF32T64>(source: T, range: T) -> T {
        match size_of::<T>() * 8 {
            32 => T::from_u32(x86_bmi_bextr_32(source.to_u32(), range.to_u32())),
            64 => T::from_u64(x86_bmi_bextr_64(source.to_u64(), range.to_u64())),
            _ => unreachable!(),
        }
    }
}

pub fn bextri<T: IntF32T64>(source: T, range: T) -> T {
    if cfg!(target_feature = "bmi") {
        unsafe { intrinsics::bextri(source, range) }
    } else {
        alg::bmi::bextri(source, range)
    }
}