ZERO (double-vector) Zero ZA double-vector groups The instruction zeroes one, two, or four ZA double-vector groups. The double-vector group within all of, each half of, or each quarter of the ZA array is selected by the sum of the vector select register and offset range, modulo all, half, or quarter the number of ZA array vectors. The vector group symbol, VGx2 or VGx4, indicates that the ZA operand consists of two or four ZA double-vector groups respectively. Green True SM_1_only It has encodings from 3 classes: One ZA double-vector , Two ZA double-vectors and Four ZA double-vectors 1 1 0 0 0 0 0 0 0 0 0 0 1 1 0 0 1 0 0 0 0 0 0 0 0 0 0 ZERO ZA.D[<Wv>, <offs1>:<offs2>] if !IsFeatureImplemented(FEAT_SME2p1) then UNDEFINED; constant integer v = UInt('010':Rv); constant integer offset = UInt(off3:'0'); constant integer ngrp = 1; constant integer nvec = 2; 1 1 0 0 0 0 0 0 0 0 0 0 1 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 ZERO ZA.D[<Wv>, <offs1>:<offs2>, VGx2] if !IsFeatureImplemented(FEAT_SME2p1) then UNDEFINED; constant integer v = UInt('010':Rv); constant integer offset = UInt(off2:'0'); constant integer ngrp = 2; constant integer nvec = 2; 1 1 0 0 0 0 0 0 0 0 0 0 1 1 0 1 1 0 0 0 0 0 0 0 0 0 0 0 ZERO ZA.D[<Wv>, <offs1>:<offs2>, VGx4] if !IsFeatureImplemented(FEAT_SME2p1) then UNDEFINED; constant integer v = UInt('010':Rv); constant integer offset = UInt(off2:'0'); constant integer ngrp = 4; constant integer nvec = 2; <Wv> Is the 32-bit name of the vector select register W8-W11, encoded in the "Rv" field. <offs1> For the one ZA double-vector variant: is the first vector select offset, encoded as "off3" field times 2. <offs1> For the four ZA double-vectors and two ZA double-vectors variant: is the first vector select offset, encoded as "off2" field times 2. <offs2> For the one ZA double-vector variant: is the second vector select offset, encoded as "off3" field times 2 plus 1. <offs2> For the four ZA double-vectors and two ZA double-vectors variant: is the second vector select offset, encoded as "off2" field times 2 plus 1. CheckStreamingSVEAndZAEnabled(); constant integer VL = CurrentVL; constant integer vectors = VL DIV 8; constant integer vstride = vectors DIV ngrp; constant bits(32) vbase = X[v, 32]; integer vec = (UInt(vbase) + offset) MOD vstride; vec = vec - (vec MOD nvec); for r = 0 to ngrp-1 for i = 0 to nvec-1 ZAvector[vec + i, VL] = Zeros(VL); vec = vec + vstride;