Unpack and widen half of predicate
This instruction unpacks elements from the lowest or highest half of the source predicate and places them in elements of twice their size within the destination predicate. This instruction is unpredicated.
It has encodings from 2 classes: High half and Low half
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| 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | Pn | 0 | Pd | ||||||
| H | |||||||||||||||||||||||||||||||
if !IsFeatureImplemented(FEAT_SVE) && !IsFeatureImplemented(FEAT_SME) then EndOfDecode(Decode_UNDEF); end; let esize : integer{} = 16; let n : integer = UInt(Pn); let d : integer = UInt(Pd); let hi : boolean = TRUE;
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| 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | Pn | 0 | Pd | ||||||
| H | |||||||||||||||||||||||||||||||
if !IsFeatureImplemented(FEAT_SVE) && !IsFeatureImplemented(FEAT_SME) then EndOfDecode(Decode_UNDEF); end; let esize : integer{} = 16; let n : integer = UInt(Pn); let d : integer = UInt(Pd); let hi : boolean = FALSE;
| <Pd> |
Is the name of the destination scalable predicate register, encoded in the "Pd" field. |
| <Pn> |
Is the name of the source scalable predicate register, encoded in the "Pn" field. |
CheckSVEEnabled(); let VL : integer{} = CurrentVL(); let PL : integer{} = VL DIV 8; let elements : integer = VL DIV esize; let operand : bits(PL) = P{}(n); var result : bits(PL); let psize : integer{} = esize DIV 8; for e = 0 to elements-1 do let pbit : bit = PredicateElement{PL}(operand, if hi then e + elements else e, esize DIV 2); result[e*:psize] = ZeroExtend{psize}(pbit); end; P{PL}(d) = result;
2026-03_rel 2026-03-26 20:48:11
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