16.108 NEG (shifted register)

Negate (shifted register).

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

The equivalent instruction is SUB Wd, WZR, Wm {, shift #amount}.

Syntax

NEG Wd, Wm{, shift #amount} ; 32-bit

NEG Xd, Xm{, shift #amount} ; 64-bit

Where:

Wd
Is the 32-bit name of the general-purpose destination register.
Wm
Is the 32-bit name of the general-purpose source register.
amount

Depends on the instruction variant:

32-bit general registers
Is the shift amount, in the range 0 to 31, defaulting to 0.
64-bit general registers
Is the shift amount, in the range 0 to 63, defaulting to 0.
Xd
Is the 64-bit name of the general-purpose destination register.
Xm
Is the 64-bit name of the 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.

Operation

Negate (shifted register) negates an optionally-shifted register value, and writes the result to the destination register.

Rd = 0 - shift(Rm, amount), where R is either W or X.

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