UDF

Permanently Undefined generates an Undefined Instruction exception (ESR_ELx.EC = 0b000000). The encodings for UDF used in this section are defined as permanently undefined in the Armv8-A architecture.

313029282726252423222120191817161514131211109876543210
0000000000000000imm16

Integer

UDF #<imm>

// The imm16 field is ignored by hardware. UNDEFINED;

Assembler Symbols

<imm>

is a 16-bit unsigned immediate, in the range 0 to 65535, encoded in the "imm16" field. The PE ignores the value of this constant.

Operation

// No operation.


Internal version only: isa v31.05b, AdvSIMD v29.02, pseudocode v2019-12_rc3_1, sve v2019-12_rc3 ; Build timestamp: 2019-12-13T11:02

Copyright © 2010-2019 Arm Limited or its affiliates. All rights reserved. This document is Non-Confidential.