2.6.5.3.2 Operation
ASR
, LSL
, LSR
, and
ROR
move the bits in the register Rm to the left or right by the number
of places specified by constant n or register Rs.
RRX
moves the bits in register Rm to the right by 1.
In all these instructions, the result is written to Rd, but the value in register Rm remains unchanged. For more information about the result generated by the different instructions, see 2.6.3.4 Shift Operations.