vcmpneb.

Vector Compare Not Equal Byte (Record)

vcmpneb. VRT,VRA,VRB

Compares each byte of two vector registers and sets the result register to all 1s if the bytes are not equal, otherwise all 0s.

Encoding

Binary Layout

0:5

VRT

6:10

VRA

11:15

VRB

16:20

21:31

Format VC-form

Opcode 0x10000007

Extension VMX (AltiVec)

Operands

vD
Target
vA
Src A
vB
Src B
VRT
Target Vector Register
VRA
Source Vector Register
VRB
Source Vector Register

Example

vcmpneb v1, v2, v3

Registers Altered

CR0, XER

Reference

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

Description

For vcmpneb, each byte of VSR[VRA+32] is compared with the corresponding byte of VSR[VRB+32]. If they are not equal, the corresponding byte in VSR[VRT+32] is set to 0xFF; otherwise, it is set to 0x00.

Operation

if MSR.VEC=0 then
    Vector_Unavailable()
all_true ←1
all_false ←1
do i = 0 to 15
    src1 ←VSR[VRA+32].byte[i]
    src2 ←VSR[VRB+32].byte[i]
    if src1 != src2 then do
        VSR[VRT+32].byte[i] ←0xFF
        all_false ←0
    end
    else do
        VSR[VRT+32].byte[i] ←0x00
        all_true ←0
    end
end
if Rc=1 then
    CR.field[6] ←all_true || 0b0 || all_false || 0b0

Programming Note

When Rc=1, CR1 is set from the FPSCR[FX, FEX, VX, OX] bits immediately after the operation completes.