Vector Multiply Accumulate Long multiplies corresponding elements in two vectors, and add the products to the corresponding element of the destination vector. The destination vector element is twice as long as the elements that are multiplied.
Depending on settings in the CPACR, NSACR, and HCPTR registers, and the Security state and PE mode in which the instruction is executed, an attempt to execute the instruction might be undefined, or trapped to Hyp mode. For more information see Enabling Advanced SIMD and floating-point support.
It has encodings from the following instruction sets: A32 ( A1 ) and T32 ( T1 ) .
| 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 | 1 | 1 | 0 | 0 | 1 | U | 1 | D | != 11 | Vn | Vd | 1 | 0 | 0 | 0 | N | 0 | M | 0 | Vm | ||||||||||
| size | op | ||||||||||||||||||||||||||||||
if size == '11' then SEE "Related encodings"; if Vd<0> == '1' then UNDEFINED; constant add = (op == '0'); constant long_destination = TRUE; constant unsigned = (U == '1'); constant esize = 8 << UInt(size); constant elements = 64 DIV esize; constant d = UInt(D:Vd); constant n = UInt(N:Vn); constant m = UInt(M:Vm); constant regs = 1;
| 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| 1 | 1 | 1 | U | 1 | 1 | 1 | 1 | 1 | D | != 11 | Vn | Vd | 1 | 0 | 0 | 0 | N | 0 | M | 0 | Vm | ||||||||||
| size | op | ||||||||||||||||||||||||||||||
if size == '11' then SEE "Related encodings"; if Vd<0> == '1' then UNDEFINED; constant add = (op == '0'); constant long_destination = TRUE; constant unsigned = (U == '1'); constant esize = 8 << UInt(size); constant elements = 64 DIV esize; constant d = UInt(D:Vd); constant n = UInt(N:Vn); constant m = UInt(M:Vm); constant regs = 1;
Related encodings: See Advanced SIMD data-processing for the T32 instruction set, or Advanced SIMD data-processing for the A32 instruction set.
| <c> |
For encoding A1: see Standard assembler syntax fields. This encoding must be unconditional. |
|
For encoding T1: see Standard assembler syntax fields. |
| <q> |
| <dt> |
Is the data type for the elements of the operands,
encoded in
|
| <Qd> |
Is the 128-bit name of the SIMD&FP destination register, encoded in the "D:Vd" field as <Qd>*2. |
| <Dn> |
Is the 64-bit name of the first SIMD&FP source register, encoded in the "N:Vn" field. |
| <Dm> |
Is the 64-bit name of the second SIMD&FP source register, encoded in the "M:Vm" field. |
if ConditionPassed() then EncodingSpecificOperations(); CheckAdvSIMDEnabled(); for r = 0 to regs-1 for e = 0 to elements-1 constant product = (Int(Elem[Din[n+r],e,esize],unsigned) * Int(Elem[Din[m+r],e,esize],unsigned)); constant addend = if add then product else -product; if long_destination then Elem[Q[d>>1],e,2*esize] = Elem[Qin[d>>1],e,2*esize] + addend; else Elem[D[d+r],e,esize] = Elem[Din[d+r],e,esize] + addend;
If CPSR.DIT is 1 and this instruction passes its condition execution check:
Internal version only: isa v01_31, pseudocode v2024-03_rel ; Build timestamp: 2024-03-25T10:05
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