lwz or l (Load Word and Zero) instruction
Purpose
Loads a word of data from a specified location in memory into a general-purpose register.
Syntax
| Bits | Value |
|---|---|
| 0 - 5 | 32 |
| 6 - 10 | RT |
| 11 - 15 | RA |
| 16 - 31 | D |
Description
The lwz and l instructions load a word in storage from a specified location in memory addressed by the effective address (EA) into the target general-purpose register (GPR) RT.
If GPR RA is not 0, the EA is the sum of the contents of GPR RA and D, a 16-bit, signed two's complement integer sign-extended to 32 bits. If GPR RA is 0, then the EA is D.
The lwz and l instructions have one syntax form and do not affect the Fixed-Point Exception Register or Condition Register Field 0.
Parameters
| Item | Description |
|---|---|
| RT | Specifies target general-purpose register where result of operation is stored. |
| D | Specifies a 16-bit, signed two's complement integer sign-extended to 32 bits for EA calculation. |
| RA | Specifies source general-purpose register for EA calculation. |
Examples
The following code loads a word from memory into GPR 6:
.csect data[rw]
# Assume GPR 5 contains address of csect data[rw].
storage: .long 0x4
.csect text[pr]
lwz 6,storage(5)
# GPR 6 now contains 0x0000 0004.