Clear user interrupt flag; user interrupts blocked when user interrupt flag cleared.
Instruction Operand Encoding
Op/En
Tuple
Operand 1
Operand 2
Operand 3
Operand 4
ZO
N/A
N/A
N/A
N/A
N/A
Description
CLUI clears the user interrupt flag (UIF). Its effect takes place immediately: a user interrupt cannot be delivered on the instruction boundary following CLUI.
An execution of CLUI inside a transactional region causes a transactional abort; the abort loads EAX as it would have had it been caused due to an execution of CLI.
Operation
UIF := 0;
Flags Affected
None.
Protected Mode Exceptions
#UD
The CLUI instruction is not recognized in protected mode.
Real-Address Mode Exceptions
#UD
The CLUI instruction is not recognized in real-address mode.
Virtual-8086 Mode Exceptions
#UD
The CLUI instruction is not recognized in virtual-8086 mode.
Compatibility Mode Exceptions
#UD
The CLUI instruction is not recognized in compatibility mode.
64-Bit Mode Exceptions
#UD
If the LOCK prefix is used.
If executed inside an enclave.
If CR4.UINTR = 0.
If CPUID.07H.0H:EDX.UINTR[bit 5] = 0.
This UNOFFICIAL, mechanically-separated, non-verified reference is provided for convenience, but it may be
incomplete or broken in various obvious or non-obvious
ways. Refer to Intel® 64 and IA-32 Architectures Software Developer’s Manual for anything serious.