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## UMLAL (multiple vectors)

Multi-vector unsigned integer multiply-add long

This unsigned integer multiply-add long instruction multiplies each unsigned 16-bit element in the two or four first source vectors with each unsigned 16-bit element in the two or four second source vectors, widens each product to 32-bits and destructively adds these values to the corresponding 32-bit elements of the ZA double-vector groups. The lowest of the two consecutive vector numbers forming the double-vector group within each half of or each quarter of the ZA array are selected by the sum of the vector select register and immediate offset, modulo half or quarter the number of ZA array vectors.

The vector group symbol, VGx2 or VGx4, indicates that the ZA operand consists of two or four ZA double-vector groups respectively. The vector group symbol is preferred for disassembly, but optional in assembler source code.

This instruction is unpredicated.

It has encodings from 2 classes: Two ZA double-vectors and Four ZA double-vectors

### Two ZA double-vectors
(FEAT_SME2)

31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0
1 | 1 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 1 | Zm | 0 | 0 | Rv | 0 | 1 | 0 | Zn | 0 | 1 | 0 | 0 | off2
|  |  |  |  |  |  | U | S |  |

####

UMLAL ZA.S[<Wv>, <offs1>:<offs2>{, VGx2}], { <Zn1>.H-<Zn2>.H }, { <Zm1>.H-<Zm2>.H }

if !HaveSME2() then UNDEFINED; constant integer esize = 32; integer v = UInt('010':Rv); integer n = UInt(Zn:'0'); integer m = UInt(Zm:'0'); integer offset = UInt(off2:'0'); constant integer nreg = 2;

### Four ZA double-vectors
(FEAT_SME2)

31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0
1 | 1 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 1 | Zm | 0 | 1 | 0 | Rv | 0 | 1 | 0 | Zn | 0 | 0 | 1 | 0 | 0 | off2
|  |  |  |  |  |  | U | S |  |

####

UMLAL ZA.S[<Wv>, <offs1>:<offs2>{, VGx4}], { <Zn1>.H-<Zn4>.H }, { <Zm1>.H-<Zm4>.H }

if !HaveSME2() then UNDEFINED; constant integer esize = 32; integer v = UInt('010':Rv); integer n = UInt(Zn:'00'); integer m = UInt(Zm:'00'); integer offset = UInt(off2:'0'); constant integer nreg = 4;

### Assembler Symbols

<Wv> | Is the 32-bit name of the vector select register W8-W11, encoded in the "Rv" field.

<offs1> | Is the vector select offset, pointing to first of two consecutive vectors, encoded as "off2" field times 2.

<offs2> | Is the vector select offset, pointing to last of two consecutive vectors, encoded as "off2" field times 2 plus 1.

<Zn1> | For the two ZA double-vectors variant: is the name of the first scalable vector register of a multi-vector sequence, encoded as "Zn" times 2.
| For the four ZA double-vectors variant: is the name of the first scalable vector register of a multi-vector sequence, encoded as "Zn" times 4.

<Zn4> | Is the name of the fourth scalable vector register of a multi-vector sequence, encoded as "Zn" times 4 plus 3.

<Zn2> | Is the name of the second scalable vector register of a multi-vector sequence, encoded as "Zn" times 2 plus 1.

<Zm1> | For the two ZA double-vectors variant: is the name of the first scalable vector register of a multi-vector sequence, encoded as "Zm" times 2.
| For the four ZA double-vectors variant: is the name of the first scalable vector register of a multi-vector sequence, encoded as "Zm" times 4.

<Zm4> | Is the name of the fourth scalable vector register of a multi-vector sequence, encoded as "Zm" times 4 plus 3.

<Zm2> | Is the name of the second scalable vector register of a multi-vector sequence, encoded as "Zm" times 2 plus 1.

### Operation

CheckStreamingSVEAndZAEnabled(); constant integer VL = CurrentVL; constant integer elements = VL DIV esize; integer vectors = VL DIV 8; integer vstride = vectors DIV nreg; bits(32) vbase = X[v, 32]; integer vec = (UInt(vbase) + offset) MOD vstride; bits(VL) result; vec = vec - (vec MOD 2); for r = 0 to nreg-1 bits(VL) operand1 = Z[n+r, VL]; bits(VL) operand2 = Z[m+r, VL]; for i = 0 to 1 bits(VL) operand3 = ZAvector[vec + i, VL]; for e = 0 to elements-1 integer element1 = UInt(Elem[operand1, 2 * e + i, esize DIV 2]); integer element2 = UInt(Elem[operand2, 2 * e + i, esize DIV 2]); bits(esize) product = (element1 * element2)<esize-1:0>; Elem[result, e, esize] = Elem[operand3, e, esize] + product; ZAvector[vec + i, VL] = result; vec = vec + vstride;

### Operational information

If PSTATE.DIT is 1:

- The execution time of this instruction is independent of:
  - The values of the data supplied in any of its registers.
  - The values of the NZCV flags.
- The response of this instruction to asynchronous exceptions does not vary based on:
  - The values of the data supplied in any of its registers.
  - The values of the NZCV flags.

Base Instructions | SIMD&FP Instructions | SVE Instructions | SME Instructions | Index by Encoding | Shared Pseudocode | Proprietary Notice

Internal version only: isa v33.64, AdvSIMD v29.12, pseudocode v2023-06_rel, sve v2023-06_rel ; Build timestamp: 2023-07-04T19:42

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