vpermxor

Vector Permute and Exclusive-OR

vpermxor vD, vA, vB, vC

Permutes bytes from vA and vB, then XORs with vC. Used for finite field arithmetic.

Encoding

Binary Layout

0

0:5

VRT

6:10

VRA

11:15

VRB

16:20

VRC

21:25

45

26:31

 

Format VA-form

Opcode 0x1000002D

Extension Vector Crypto

Operands

• vD
  Target
• vA
  Src A
• vB
  Src B
• vC
  Permute
• VRT
  Target Vector Register
• VRA
  Source Vector Register
• VRB
  Source Vector Register
• VRC
  Control Vector Register

Example

vpermxor vd, va, vb, vc

Registers Altered

MSR

Related

More in Vector Crypto

Reference

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

Description

Permutes bytes from vA and vB according to the permutation control vector vC, then XORs the result with vC. This instruction is used for finite field arithmetic operations in cryptographic algorithms within the Vector Crypto extension. No status flags are affected.

Operation

temp ← Permute(vA || vB, vC); vD ← temp XOR vC

Programming Note

The vpermxor instruction requires the Vector Facility to be enabled in the MSR. Ensure that the index values in VRC do not exceed 15 to avoid undefined behavior. This instruction operates on byte-level data and is useful for complex data transformations involving permutation and bitwise operations.