Function miri::shims::x86::sse2::extract_first_u64

fn extract_first_u64<'tcx>(
    this: &MiriInterpCx<'_, 'tcx>,
    op: &MPlaceTy<'tcx, Provenance>
) -> InterpResult<'tcx, u64>

Takes a 128-bit vector, transmutes it to [u64; 2] and extracts the first value.