Count non-zero bits (predicated)
Count non-zero bits in each active element of the source vector, and place the results in the corresponding elements of the destination vector. Inactive elements in the destination vector register remain unmodified.
| 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 | 0 | size | 0 | 1 | 1 | 0 | 1 | 0 | 1 | 0 | 1 | Pg | Zn | Zd | |||||||||||
if !HaveSVE() && !HaveSME() then UNDEFINED; integer esize = 8 << UInt(size); integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Zd);
| <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 source scalable vector register, encoded in the "Zn" field. |
CheckSVEEnabled(); integer elements = VL DIV esize; bits(PL) mask = P[g]; bits(VL) operand = if AnyActiveElement(mask, esize) then Z[n] else Zeros(); bits(VL) result = Z[d]; for e = 0 to elements-1 if ElemP[mask, e, esize] == '1' then bits(esize) element = Elem[operand, e, esize]; Elem[result, e, esize] = BitCount(element)<esize-1:0>; Z[d] = result;
This instruction might be immediately preceded in program order by a MOVPRFX instruction. The MOVPRFX instruction must conform to all of the following requirements, otherwise the behavior of the MOVPRFX and this instruction is unpredictable:
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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