msgsndp

Message Send Privileged

msgsndp RB

Sends a message to other threads on the same processor or sub-processor.

Encoding

Binary Layout

31

0:5

/

6:10

/

11:15

RB

16:20

142

21:30

/

31

 

Format X-form

Opcode 0x7C00011C

Extension Privileged

Operands

• RB
  Type

Example

msgsndp r5

Registers Altered

DPDES

Related

More in Privileged

Reference

View in PowerISA v3.1C Specification ↗ OPF Power ISA v3.1C

Description

The instruction sends a message to other threads based on the contents of RB. The message type and destination thread(s) are specified in RB.

Operation

msgtype ← (RB)32:36
payload ← (RB)37:63
t ← (RB)57:63
if msgtype = 5 and t ≤ maximum privileged thread number on processor or sub-processor then
    DPDES63-t ← 1
    send_msg(msgtype, payload, t)

Programming Note

If msgsndp is used to notify the receiver that updates have been made to storage, a lwsync or sync should be placed between the stores and the msgsndp. See Section 6.9.2.