or.

OR Record

or. RT,RA,RB

Performs a bitwise OR operation on the contents of two registers and updates the condition register.

Encoding

Binary Layout

18

0:5

LI

6:29

AA

30

LK

31

 

Format X-form

Opcode 0x7C000378

Extension Base

Operands

• RT
  Target General Purpose Register
• RA
  Source General Purpose Register
• RB
  Source General Purpose Register

Example

or. r3, r4, r5

Registers Altered

CR0, XER

Related

More in Base

Reference

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

Description

For or., the bitwise OR of the contents of register RA and RB is placed into register RT.

Operation

if 'or.' then
    RT <- (RA) OR (RB)

Programming Note

The or. instruction performs a bitwise OR operation between two registers, storing the result in another register. This instruction does not require any special alignment and can be executed at any privilege level. It is commonly used for combining flags or setting specific bits in a register.