msgclr

Message Clear

msgclr RB

Clears a pending doorbell interrupt (Inter-processor comms).

Details

Clears a pending doorbell or message interrupt from another processor, based on the message type specified in RB. This is a privileged instruction used for inter-processor communication and does not affect condition registers.

Pseudocode Operation

clear_pending_message(RB[62:63])

Programming Note

Use msgclr to clear messages accepted by the current thread. If clearing a message of type 0x05, it also clears any associated Directed Ultravisor Doorbell exception. This instruction is typically used in hypervisor environments where message handling and doorbell management are required.

Example

msgclr r5

Encoding

Binary Layout
31
0
/
6
/
11
RB
16
118
21
/
31
 
Format X-form
Opcode 0x7C0001DC
Extension Privileged

Operands

  • RB
    Message Type