Load a double-word of data into the specified general purpose register, updating the address base.
This instruction should only be used on 64-bit PowerPC processors running a 64-bit application.
| PowerPC64 | |
|---|---|
| ldu | RT, D(RA) |
The ldu instruction loads a double-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, fullword-aligned, sign-extended to 64 bits.
If RA = 0 or RA = RT, the instruction form is invalid.
The following code loads the first of 4 double-words from memory into GPR 4, incrementing GPR 5 to point to the next double-word in memory:
.csect foodata[rw]
storage: .llong 5,6,7,12 # Successive double-words.
.csect text[PR]
# Assume GPR 5 contains address of csect foodata[RW].
ldu 4,storage(5) # GPR 4 now contains the first double-word of
# foodata; GRP 5 points to the second double-word.
This instruction is defined only for 64-bit implementations. Using it on a 32-bit implementation will cause the system illegal instruction error handler to be invoked.
Fixed-Point Load and Store with Update Instructions