CMP (shifted register)
Compare (shifted register)
This instruction subtracts an optionally-shifted register
value from a register value. It updates the condition flags based
on the result, and discards the result.
If PSTATE.DIT is 1:
The execution time of this instruction is independent of:
The values of the data supplied in any of its registers.
The values of the NZCV flags.
The response of this instruction to asynchronous exceptions does not vary based on:
The values of the data supplied in any of its registers.
The values of the NZCV flags.
SUBS (shifted register)
1
1
0
1
0
1
1
0
1
1
1
1
1
0
CMP <Wn>, <Wm>{, <shift> #<amount>}
SUBS WZR, <Wn>, <Wm>{, <shift> #<amount>}
Unconditionally
1
CMP <Xn>, <Xm>{, <shift> #<amount>}
SUBS XZR, <Xn>, <Xm>{, <shift> #<amount>}
Unconditionally
<Wn>
Is the 32-bit name of the first general-purpose source register, encoded in the "Rn" field.
<Wm>
Is the 32-bit name of the second general-purpose source register, encoded in the "Rm" field.
<shift>
Is the optional shift type to be applied to the second source operand, defaulting to LSL and
shift
<shift>
00
LSL
01
LSR
10
ASR
11
RESERVED
<amount>
For the 32-bit variant: is the shift amount, in the range 0 to 31, defaulting to 0 and encoded in the "imm6" field.
<amount>
For the 64-bit variant: is the shift amount, in the range 0 to 63, defaulting to 0 and encoded in the "imm6" field.
<Xn>
Is the 64-bit name of the first general-purpose source register, encoded in the "Rn" field.
<Xm>
Is the 64-bit name of the second general-purpose source register, encoded in the "Rm" field.