ldux (Load Doubleword with Update Indexed) instruction
Purpose
Loads a doubleword of data from a specified memory location into a general purpose register (GPR), and updates the address base.
Syntax
| Bits | Value |
|---|---|
| 0 - 5 | 31 |
| 6 - 10 | D |
| 11 - 15 | A |
| 16 - 20 | B |
| 21 - 30 | 53 |
| 31 | 0 |
Description
The effective address (EA) is calculated from the sum of the GPR, RA and RB. A doubleword of data is read from the memory location that is referenced by the EA and placed into GPR RT. GPR RA is updated with the EA.
If RA equals 0 or RA equals RD, the instruction form is invalid.
Parameters
| Item | Description |
|---|---|
| RT | Specifies the source GPR for the stored data. |
| RA | Specifies source GPR for the EA calculation. |
| RB | Specifies source GPR for the EA calculation. |
Implementation
This instruction is defined only for 64-bit implementations. Using it on a 32-bit implementation calls the system illegal instruction error handler.