Intel ITANIUM ARCHITECTURE - SOFTWARE DEVELOPERS MANUAL VOLUME 1 REV 2.3 Manual page 1685

UD2—Undefined Instruction
Opcode
0F 0B
Description
Generates an invalid opcode. This instruction is provided for software testing to
explicitly generate an invalid opcode. The opcode for this instruction is reserved for this
purpose.
Other than raising the invalid opcode exception, this instruction is the same as the NOP
instruction.
Operation
IF Itanium System Environment THEN IA-32_Intercept(INST,0F0B);
#UD (* Generates invalid opcode exception *);
Flags Affected
None.
Additional Itanium System Environment Exceptions
IA-32_Intercept
Exceptions (All Operating Modes)
#UD
Volume 4: Base IA-32 Instruction Reference
Instruction Description
UD2 Raise invalid opcode exception
Mandatory Instruction Intercept.
Instruction is guaranteed to raise an invalid opcode exception in all
operating modes).
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