vextuwrx

Vector Extract Unsigned Word to GPR using GPR-specified Right-Index VX-form

vextuwrx VRT,RA,RB

Extracts an unsigned word from a vector register and places it into a general-purpose register.

Encoding

Binary Layout

000100

0:5

VRT

6:10

11:15

16:20

10100

21:25

001100

26:31

Format VX-form

Opcode 0x1000078D

Extension VMX (AltiVec)

Operands

VRT
Target Vector Register
RA
Source General Purpose Register (index)
RB
Source Vector Register

Example

vextuwrx v1, r4, r5

Reference

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

Description

Extracts a 32-bit unsigned word from vector register RB using a byte-offset index contained in GPR RA, and places the extracted value into GPR VRT. The index specifies which 4-byte element to extract from the 128-bit vector. This instruction requires VMX/AltiVec support and no condition flags are affected.

Operation

idx ← (RA)[29:31] || 0b00
VRT ← (RB)[idx*8 : idx*8+31]

Programming Note

Use vextuwrx to extract a 32-bit unsigned word from a vector register using a right-index specified by a GPR. Ensure the index is correctly calculated to avoid out-of-bounds access. The result is zero-extended to 64 bits before being stored in the target GPR.