zip2

Vector Zip 2 (Interleave)

ZIP2 <Vd>.<T>, <Vn>.<T>, <Vm>.<T>

Interleaves the upper halves of two vectors.

Pseudocode Operation

bits(128) result;
for e = 0 to (esize/8)-1
  result[e*16 +: 8] ← Vn[(e+half)*16 +: 8];
  result[e*16 + 8 +: 8] ← Vm[(e+half)*16 +: 8];
if Q == 0 then
  Vd ← result[0 +: 64];
else
  Vd ← result;

Example

ZIP2 v0.4s.T, v1.4s.T, v2.4s.T

Encoding

Binary Layout
0
31
Q
30
001110
29:24
size
23:22
0
21
Rm
20:16
0
15
1
14
1110
13:10
Rn
9:5
Rd
4:0
 
Format SIMD Permute
Opcode 0x0E007800
Extension NEON (SIMD)

Operands

  • Vd
    Destination SIMD/FP vector register
  • Vn
    First source SIMD/FP vector register
  • Vm
    Second source SIMD/FP vector register

Related

Other forms of zip2

More in NEON (SIMD)

Reference

View in Arm A64 ISA Reference ↗ Arm A64 ISA

Instruction Forms

Encoding Instruction ISA Bit pattern
0x05204400 ZIP2 <Pd>.<T>, <Pn>.<T>, <Pm>.<T> A64 00000101 | size | 10 | Pm | 010 | 0 | 0 | 1 | 0 | Pn | 0 | Pd
0x05206400 ZIP2 <Zd>.<T>, <Zn>.<T>, <Zm>.<T> A64 00000101 | size | 1 | Zm | 011 | 00 | 1 | Zn | Zd
0x05A00400 ZIP2 <Zd>.Q, <Zn>.Q, <Zm>.Q A64 00000101101 | Zm | 000 | 0 | 0 | 1 | Zn | Zd
0x0E007800 ZIP2 <Vd>.<T>, <Vn>.<T>, <Vm>.<T> A64 0 | Q | 001110 | size | 0 | Rm | 0 | 1 | 1110 | Rn | Rd

Description

Zip vectors (secondary). This instruction reads adjacent vector elements from the upper half of two source SIMD&FP registers as pairs, interleaves the pairs and places them into a vector, and writes the vector to the destination SIMD&FP register. The first pair from the first source register is placed into the two lowest vector elements, with subsequent pairs taken alternately from each source register. Depending on the settings in the CPACR_EL1, CPTR_EL2, and CPTR_EL3 registers, and the current Security state and Exception level, an attempt to execute the instruction might be trapped.

Operation

CheckFPAdvSIMDEnabled64();
bits(datasize) operand1 = V[n, datasize];
bits(datasize) operand2 = V[m, datasize];
bits(datasize) result;

integer base = part * pairs;

for p = 0 to pairs-1
    Elem[result, 2*p+0, esize] = Elem[operand1, base+p, esize];
    Elem[result, 2*p+1, esize] = Elem[operand2, base+p, esize];

V[d, datasize] = result;