Copy Active vector elements to lower-numbered elements
This instruction copies Active elements from the source vector to consecutive elements of the destination vector, in increasing order of element number, and sets any remaining elements to zero.
This instruction is illegal when executed in Streaming SVE mode, unless FEAT_SME_FA64 is implemented and enabled, or FEAT_SME2p2 is implemented.
It has encodings from 2 classes: Byte and halfword and Word and doubleword
| 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 | 0 | sz | 1 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | Pg | Zn | Zd | ||||||||||
if !IsFeatureImplemented(FEAT_SVE2p2) && !IsFeatureImplemented(FEAT_SME2p2) then EndOfDecode(Decode_UNDEF); end; let esize : integer{} = 8 << UInt(sz); let g : integer = UInt(Pg); let n : integer = UInt(Zn); let d : integer = UInt(Zd);
| 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 | 1 | sz | 1 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | Pg | Zn | Zd | ||||||||||
if !IsFeatureImplemented(FEAT_SVE) && !IsFeatureImplemented(FEAT_SME2p2) then EndOfDecode(Decode_UNDEF); end; let esize : integer{} = 32 << UInt(sz); let g : integer = UInt(Pg); let n : integer = UInt(Zn); let d : integer = UInt(Zd);
| <Zd> |
Is the name of the destination scalable vector register, encoded in the "Zd" field. |
| <T> |
For the "Byte and halfword" variant: is the size specifier,
encoded in
| ||||||
|
For the "Word and doubleword" variant: 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. |
if IsFeatureImplemented(FEAT_SME2p2) then CheckSVEEnabled(); else CheckNonStreamingSVEEnabled(); end; let VL : integer{} = CurrentVL(); let PL : integer{} = VL DIV 8; let elements : integer = VL DIV esize; let mask : bits(PL) = P{}(g); let operand1 : bits(VL) = if AnyActiveElement{PL}(mask, esize) then Z{VL}(n) else Zeros{VL}; var result : bits(VL) = Zeros{}; var x : integer = 0; for e = 0 to elements-1 do if ActivePredicateElement{PL}(mask, e, esize) then let element : bits(esize) = operand1[e*:esize]; result[x*:esize] = element; x = x + 1; end; end; Z{VL}(d) = result;
2026-03_rel 2026-03-26 20:48:11
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