Signed add and accumulate long pairwise
Add pairs of adjacent signed integer values and accumulate the results into the overlapping double-width elements of the destination vector.
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 |
0 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | size | 0 | 0 | 0 | 1 | 0 | 0 | 1 | 0 | 1 | Pg | Zn | Zda | |||||||||||
U |
if !IsFeatureImplemented(FEAT_SVE2) && !IsFeatureImplemented(FEAT_SME) then UNDEFINED; if size == '00' then UNDEFINED; constant integer esize = 8 << UInt(size); constant integer g = UInt(Pg); constant integer n = UInt(Zn); constant integer da = UInt(Zda);
<Zda> |
Is the name of the second source and destination scalable vector register, encoded in the "Zda" field. |
<T> |
Is the size specifier,
encoded in
|
<Pg> |
Is the name of the governing scalable predicate register P0-P7, encoded in the "Pg" field. |
<Zn> |
Is the name of the first source scalable vector register, encoded in the "Zn" field. |
<Tb> |
Is the size specifier,
encoded in
|
CheckSVEEnabled(); constant integer VL = CurrentVL; constant integer PL = VL DIV 8; constant integer elements = VL DIV esize; constant bits(PL) mask = P[g, PL]; constant bits(VL) operand_acc = Z[da, VL]; constant bits(VL) operand_src = if AnyActiveElement(mask, esize) then Z[n, VL] else Zeros(VL); bits(VL) result; for e = 0 to elements-1 if !ActivePredicateElement(mask, e, esize) then Elem[result, e, esize] = Elem[operand_acc, e, esize]; else constant integer element1 = SInt(Elem[operand_src, 2*e + 0, esize DIV 2]); constant integer element2 = SInt(Elem[operand_src, 2*e + 1, esize DIV 2]); constant bits(esize) sum = (element1 + element2)<esize-1:0>; Elem[result, e, esize] = Elem[operand_acc, e, esize] + sum; Z[da, VL] = result;
If FEAT_SVE2 is implemented or FEAT_SME is implemented, then if PSTATE.DIT is 1:
This instruction might be immediately preceded in program order by a MOVPRFX instruction. The MOVPRFX must conform to all of the following requirements, otherwise the behavior of the MOVPRFX and this instruction is constrained unpredictable:
Internal version only: aarchmrs v2024-03_relA, pseudocode v2024-03_rel, sve v2024-03_rel ; Build timestamp: 2024-03-26T09:45
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