You copied the Doc URL to your clipboard.

CMP (shifted register)

Compare (shifted register).

This instruction is an alias of SUBS (shifted register).

Syntax

CMP Wn, Wm{, shift #amount} ; 32-bit general registers

Equivalent to SUBS WZR, Wn, Wm {, shift #amount}

CMP Xn, Xm{, shift #amount} ; 64-bit general registers

Equivalent to SUBS XZR, Xn, Xm {, shift #amount}

Where:

Wn

Is the 32-bit name of the first general-purpose source register.

Wm

Is the 32-bit name of the second general-purpose source register.

amount

The value depends on the instruction variant:

32-bit general registers

The shift amount, in the range 0 to 31, defaulting to 0.

64-bit general registers

The shift amount, in the range 0 to 63, defaulting to 0.

Xn

Is the 64-bit name of the first general-purpose source register.

Xm

Is the 64-bit name of the second general-purpose source register.

shift

Is the optional shift type to be applied to the second source operand, defaulting to LSL, and can be one of LSL, LSR, or ASR.

Usage

Compare (shifted register) subtracts an optionally-shifted register value from a register value. It updates the condition flags based on the result, and discards the result.

Was this page helpful? Yes No