Extract last element to SIMD&FP scalar register
If there is an active element then extract the last active element from the final source vector register. If there are no active elements, extract the highest-numbered element. Then place the extracted element in the destination SIMD&FP register.
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 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | size | 1 | 0 | 0 | 0 | 1 | 1 | 1 | 0 | 0 | Pg | Zn | Vd | |||||||||||
B |
if !IsFeatureImplemented(FEAT_SVE) && !IsFeatureImplemented(FEAT_SME) then UNDEFINED; constant integer esize = 8 << UInt(size); constant integer g = UInt(Pg); constant integer n = UInt(Zn); constant integer d = UInt(Vd); constant boolean isBefore = TRUE;
<V> |
Is a width specifier,
encoded in
|
<d> |
Is the number [0-31] of the destination SIMD&FP register, encoded in the "Vd" field. |
<Pg> |
Is the name of the governing scalable predicate register P0-P7, encoded in the "Pg" field. |
<Zn> |
Is the name of the source scalable vector register, encoded in the "Zn" field. |
<T> |
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 = Z[n, VL]; integer last = LastActiveElement(mask, esize); if isBefore then if last < 0 then last = elements - 1; else last = last + 1; if last >= elements then last = 0; V[d, esize] = Elem[operand, last, esize];
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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