lxvrdx

Load VSX Vector Rightmost Doubleword Indexed X-form

lxvrdx XT,RA,RB

Loads a doubleword from memory into the rightmost element of a VSX vector register.

Details

Loads a 64-bit doubleword from memory and places it in the rightmost (least significant) doubleword element of a VSX register, with the left doubleword set to 0. The effective address is computed as RA|0 + RB. No status fields are modified by this instruction.

Pseudocode Operation

EA ← (RA=0 ? 0 : GPR[RA]) + GPR[RB]
VSR[XT] ← (0x0000000000000000 || MEM(EA, 8))

Programming Note

The lxvrdx instruction is used to load a doubleword from memory into the rightmost element of a VSX vector register. Ensure that the VSX facility is enabled in the MSR register; otherwise, a VSX_Unavailable exception will be raised. The address calculation uses two general-purpose registers, RA and RB, where RA can be zero. Be cautious of alignment requirements for optimal performance and to avoid potential exceptions.

Example

lxvrdx vs1, r4, r5

Encoding

Binary Layout
0
0
T
6
RA
11
RB
16
109
21
TX
26
 
Format X-form
Opcode 0x7C0000DA
Extension VSX
Registers Altered MSR

Operands

  • XT
    Target VSX Vector Register
  • RA
    Source General Purpose Register (address base)
  • RB
    Source General Purpose Register (offset)