SEL (predicates) Conditionally select elements from two predicates Read active elements from the first source predicate and inactive elements from the second source predicate and place in the corresponding elements of the destination predicate. Does not set the condition flags. Green True True This instruction is used by the alias MOV (predicate, predicated, merging) Pd == Pm See below for details of when the alias is preferred. 0 0 1 0 0 1 0 1 0 0 0 0 0 1 1 1 SEL <Pd>.B, <Pg>, <Pn>.B, <Pm>.B if !IsFeatureImplemented(FEAT_SVE) && !IsFeatureImplemented(FEAT_SME) then UNDEFINED; constant integer esize = 8; constant integer g = UInt(Pg); constant integer n = UInt(Pn); constant integer m = UInt(Pm); constant integer d = UInt(Pd); <Pd> Is the name of the destination scalable predicate register, encoded in the "Pd" field. <Pg> Is the name of the governing scalable predicate register, encoded in the "Pg" field. <Pn> Is the name of the first source scalable predicate register, encoded in the "Pn" field. <Pm> Is the name of the second source scalable predicate register, encoded in the "Pm" field. Alias Conditions CheckSVEEnabled(); constant integer VL = CurrentVL; constant integer PL = VL DIV 8; constant integer elements = VL DIV esize; constant bits(PL) mask = P[g, PL]; constant bits(PL) operand1 = P[n, PL]; constant bits(PL) operand2 = P[m, PL]; bits(PL) result; constant integer psize = esize DIV 8; for e = 0 to elements-1 constant bit element1 = PredicateElement(operand1, e, esize); constant bit element2 = PredicateElement(operand2, e, esize); if ActivePredicateElement(mask, e, esize) then Elem[result, e, psize] = ZeroExtend(element1, psize); else Elem[result, e, psize] = ZeroExtend(element2, psize); P[d, PL] = result;