vcmpneb

Vector Compare Not Equal Byte

vcmpneb VRT,VRA,VRB
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.

Details

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.

Pseudocode 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.

Example

vcmpneb v1, v2, v3

Encoding

Binary Layout
4
0
VRT
6
VRA
11
VRB
16
Rc
21
 
Format VC-form
Opcode 0x10000007
Extension VMX (AltiVec)
Registers Altered CR0, XER

Operands

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