Predicate extract from predicate-as-counter
Converts the source predicate-as-counter into a four register wide predicate-as-mask, and copies the portion of the mask value selected by the portion index to the destination predicate register. A portion corresponds to a one predicate register fraction of the wider predicate-as-mask value.
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 | 1 | 0 | 0 | 1 | 0 | 1 | size | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 0 | 0 | imm2 | PNn | 1 | Pd |
if !IsFeatureImplemented(FEAT_SME2) && !IsFeatureImplemented(FEAT_SVE2p1) then UNDEFINED; constant integer esize = 8 << UInt(size); constant integer n = UInt('1':PNn); constant integer d = UInt(Pd); constant integer part = UInt(imm2);
<Pd> |
Is the name of the destination scalable predicate register, encoded in the "Pd" field. |
<T> |
Is the size specifier,
encoded in
|
<PNn> |
Is the name of the first source scalable predicate register PN8-PN15, with predicate-as-counter encoding, encoded in the "PNn" field. |
<imm> |
Is the portion index, in the range 0 to 3, encoded in the "imm2" field. |
if IsFeatureImplemented(FEAT_SVE2p1) then CheckSVEEnabled(); else CheckStreamingSVEEnabled(); constant integer VL = CurrentVL; constant integer PL = VL DIV 8; constant integer elements = VL DIV esize; constant bits(PL) pred = P[n, PL]; constant bits(PL*4) mask = CounterToPredicate(pred<15:0>, PL*4); bits(PL) result; constant integer psize = esize DIV 8; for e = 0 to elements-1 constant bit pbit = PredicateElement(mask, part * elements + e, esize); Elem[result, e, psize] = ZeroExtend(pbit, psize); P[d, PL] = result;
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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