Count matching elements in vector
This instruction compares each active 32 or 64-bit element of the first source vector with all active elements with an element number less than or equal to its own in the second source vector, and places the count of matching elements in the corresponding element of the destination vector. Inactive elements in the destination vector are set to zero.
| 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 | 1 | size | 1 | Zm | 1 | 1 | 0 | Pg | Zn | Zd | |||||||||||||||
if !HaveSVE2() then UNDEFINED; if size == '0x' then UNDEFINED; integer esize = 8 << UInt(size); integer g = UInt(Pg); integer d = UInt(Zd); integer n = UInt(Zn); integer m = UInt(Zm);
| <Zd> |
Is the name of the destination scalable vector register, encoded in the "Zd" 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. |
| <Zm> |
Is the name of the second source scalable vector register, encoded in the "Zm" field. |
CheckNonStreamingSVEEnabled(); integer elements = VL DIV esize; bits(PL) mask = P[g]; bits(VL) operand1 = if AnyActiveElement(mask, esize) then Z[n] else Zeros(); bits(VL) operand2 = if AnyActiveElement(mask, esize) then Z[m] else Zeros(); bits(VL) result; for e = 0 to elements-1 integer count = 0; if ElemP[mask, e, esize] == '1' then bits(esize) element1 = Elem[operand1, e, esize]; for i = 0 to e if ElemP[mask, i, esize] == '1' then bits(esize) element2 = Elem[operand2, i, esize]; if element1 == element2 then count = count + 1; Elem[result, e, esize] = count<esize-1:0>; Z[d] = result;
Internal version only: isa v33.11seprel, AdvSIMD v29.05, pseudocode v2021-09_rel, sve v2021-09_rc3d ; Build timestamp: 2021-10-06T11:41
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