HALT

Operation

Halt the executing logical processor until an asynchronous architectural event is admitted.

Assembler Syntax

HALT

Privilege

Supervisor only

HALT retires with the following instruction as its continuation, then applies the Architectural Event Processing Model's event priority and admission rules at that instruction boundary. If the model selects an event, it delivers that event with the continuation as its saved PC before entering the halted state.

Otherwise, the executing logical processor stops instruction fetch. When an asynchronous architectural event later becomes admissible, the logical processor leaves the halted state by delivering that event with the continuation as its saved PC. Event delivery precedes execution of the continuation. Only the executing logical processor enters the halted state.

2.75in

Encodings

HALT

Format: Instruction format for HALT