title: ARM NEON: How do I bit-shift a whole 64-bit d register?
body: <p>I want to logically left or right shift a <code>d</code> register (64-bit) by an arbitrary number of bits, with the count in another register.  (Not an assemble-time constant.)</p>
  
  <p>It contains integer values and what I need to do is, to "move" them to the right position inside the register.  Only zeros should be shifted into the register at the "ends", so this is a logical shift, not arithmetic.</p>
  
  <p>I want to shift the whole register without any element boundaries.</p>
  
  <p>I have thought about using <code>vshl</code> and <code>vshr</code>, but they shift the register as separate SIMD elements and not the whole register as one "value".</p>