Unpack and widen half of predicate
Unpack elements from the lowest or highest half of the source predicate and place 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 !HaveSVE() && !HaveSME() then UNDEFINED; constant integer esize = 16; integer n = UInt(Pn); integer d = UInt(Pd); boolean hi = 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 !HaveSVE() && !HaveSME() then UNDEFINED; constant integer esize = 16; integer n = UInt(Pn); integer d = UInt(Pd); boolean hi = 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(); constant integer VL = CurrentVL; constant integer PL = VL DIV 8; constant integer elements = VL DIV esize; bits(PL) operand = P[n, PL]; bits(PL) result; for e = 0 to elements-1 ElemP[result, e, esize] = ElemP[operand, if hi then e + elements else e, esize DIV 2]; P[d, PL] = result;
If FEAT_SVE2 is implemented or FEAT_SME is implemented, then when PSTATE.DIT is 1:
Internal version only: isa v33.53, AdvSIMD v29.11, pseudocode v2022-09_rel, sve v2022-09_rel ; Build timestamp: 2022-09-30T16:37
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