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AI-generatedUndefined instruction fault in ARM64 assembly code
The UDF (Undefined Instruction) error in ARM64 occurs when the processor encounters an unrecognized or unsupported instruction. This error is deliberately triggered by the UDF opcode ( 0xD65F03C0 ) or invalid instruction encodings, causing a synchronous exception. During development, the UDF instruction is often used to mark unreachable code or debug specifi