ST1B (scalar plus immediate, single register) Contiguous store bytes from vector (immediate index) Contiguous store of bytes from elements of a vector register to the memory address generated by a 64-bit scalar base and immediate index in the range -8 to 7 which is multiplied by the vector's in-memory size, irrespective of predication, and added to the base address. Inactive elements are not written to memory. Green True True True 1 1 1 0 0 1 0 0 0 0 1 1 1 ST1B { <Zt>.<T> }, <Pg>, [<Xn|SP>{, #<imm>, MUL VL}] if !IsFeatureImplemented(FEAT_SVE) && !IsFeatureImplemented(FEAT_SME) then UNDEFINED; constant integer t = UInt(Zt); constant integer n = UInt(Rn); constant integer g = UInt(Pg); constant integer esize = 8 << UInt(size); constant integer msize = 8; constant integer offset = SInt(imm4); <Zt> Is the name of the scalable vector register to be transferred, encoded in the "Zt" field. <T> Is the size specifier, size <T> 00 B 01 H 10 S 11 D
<Pg> Is the name of the governing scalable predicate register P0-P7, encoded in the "Pg" field. <Xn|SP> Is the 64-bit name of the general-purpose base register or stack pointer, encoded in the "Rn" field. <imm> Is the optional signed immediate vector offset, in the range -8 to 7, defaulting to 0, encoded in the "imm4" field.
CheckSVEEnabled(); constant integer VL = CurrentVL; constant integer PL = VL DIV 8; constant integer elements = VL DIV esize; bits(64) base; constant bits(PL) mask = P[g, PL]; bits(64) addr; bits(VL) src; constant integer mbytes = msize DIV 8; constant boolean contiguous = TRUE; constant boolean nontemporal = FALSE; constant boolean tagchecked = n != 31; constant AccessDescriptor accdesc = CreateAccDescSVE(MemOp_STORE, nontemporal, contiguous, tagchecked); if !AnyActiveElement(mask, esize) then if n == 31 && ConstrainUnpredictableBool(Unpredictable_CHECKSPNONEACTIVE) then CheckSPAlignment(); else if n == 31 then CheckSPAlignment(); src = Z[t, VL]; base = if n == 31 then SP[] else X[n, 64]; addr = AddressAdd(base, offset * elements * mbytes, accdesc); for e = 0 to elements-1 if ActivePredicateElement(mask, e, esize) then Mem[addr, mbytes, accdesc] = Elem[src, e, esize]<msize-1:0>; addr = AddressIncrement(addr, mbytes, accdesc);