ST1Q

Scatter store quadwords

Scatter store of quadwords from the active elements of a vector register to the memory addresses generated by a vector base plus a 64-bit unscaled scalar register offset. Inactive elements are not written to memory.

This instruction is illegal when executed in Streaming SVE mode, unless FEAT_SME_FA64 is implemented and enabled.

SVE2
(FEAT_SVE2p1)

313029282726252423222120191817161514131211109876543210
11100100001Rm001PgZnZt

ST1Q { <Zt>.Q }, <Pg>, [<Zn>.D{, <Xm>}]

if !HaveSVE2p1() then UNDEFINED; integer t = UInt(Zt); integer n = UInt(Zn); integer m = UInt(Rm); integer g = UInt(Pg);

Assembler Symbols

<Zt>

Is the name of the scalable vector register to be transferred, encoded in the "Zt" field.

<Pg>

Is the name of the governing scalable predicate register P0-P7, encoded in the "Pg" field.

<Zn>

Is the name of the base scalable vector register, encoded in the "Zn" field.

<Xm>

Is the optional 64-bit name of the general-purpose offset register, defaulting to XZR, encoded in the "Rm" field.

Operation

constant integer VL = CurrentVL; constant integer PL = VL DIV 8; CheckNonStreamingSVEEnabled(); constant integer elements = VL DIV 128; bits(PL) mask = P[g, PL]; bits(VL) base; bits(64) offset; bits(VL) src; boolean contiguous = FALSE; boolean nontemporal = FALSE; boolean tagchecked = TRUE; AccessDescriptor accdesc = CreateAccDescSVE(MemOp_STORE, nontemporal, contiguous, tagchecked); if AnyActiveElement(mask, 128) then base = Z[n, VL]; offset = X[m, 64]; src = Z[t, VL]; for e = 0 to elements-1 if ActivePredicateElement(mask, e, 128) then bits(64) baddr = Elem[base, 2*e, 64]; bits(64) addr = GenerateAddress(baddr, offset, accdesc); Mem[addr, 16, accdesc] = Elem[src, e, 128];

Operational information

If PSTATE.DIT is 1, the timing of this instruction is insensitive to the value of the data being loaded or stored when its governing predicate register contains the same value for each execution.


Internal version only: aarchmrs v2023-12_rel, pseudocode v2023-12_rel, sve v2023-12_rel ; Build timestamp: 2023-12-15T16:46

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