Function simd_cast 

fn simd_cast<'ll, 'tcx>(
    bx: &mut GenericBuilder<'_, 'll, FullCx<'ll, 'tcx>>,
    name: Symbol,
    args: &[OperandRef<'tcx, &'ll Value>],
    llret_ty: &'ll Type,
    in_elem: Ty<'tcx>,
    out_elem: Ty<'tcx>,
) -> Option<&'ll Value>

Implementation of core::intrinsics::simd_cast, re-used by core::scalable::sve_cast.