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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.
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