An unsigned 20-bit offset added to the base address to get memory address.
Size: 1 dword.
Operands: :ref:`s<amdgpu_synid_s>`, :ref:`vcc<amdgpu_synid_vcc>`, :ref:`ttmp<amdgpu_synid_ttmp>`, :ref:`null<amdgpu_synid_null>`, :ref:`m0<amdgpu_synid_m0>`, :ref:`uimm20<amdgpu_synid_uimm20>`