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LD1D (vector plus immediate)

Gather load doublewords to vector (immediate index).

Gather load of doublewords to active elements of a vector register from memory addresses generated by a vector base plus immediate index. The index is a multiple of 8 in the range 0 to 248. Inactive elements will not read Device memory or signal faults, and are set to zero in the destination vector.



LD1D { <Zt>.D }, <Pg>/Z, [<Zn>.D{, #<imm>}]

if !HaveSVE() then UNDEFINED;
integer t = UInt(Zt);
integer n = UInt(Zn);
integer g = UInt(Pg);
integer esize = 64;
integer msize = 64;
boolean unsigned = TRUE;
integer offset = UInt(imm5);

Assembler Symbols


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


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


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


Is the optional unsigned immediate byte offset, a multiple of 8 in the range 0 to 248, defaulting to 0, encoded in the "imm5" field.


integer elements = VL DIV esize;
bits(VL) base = Z[n];
bits(64) addr;
bits(PL) mask = P[g];
bits(VL) result;
bits(msize) data;
constant integer mbytes = msize DIV 8;

if HaveMTEExt() then SetNotTagCheckedInstruction(FALSE);

for e = 0 to elements-1
    if ElemP[mask, e, esize] == '1' then
        addr = ZeroExtend(Elem[base, e, esize], 64) + offset * mbytes;
        data = Mem[addr, mbytes, AccType_NORMAL];
        Elem[result, e, esize] = Extend(data, esize, unsigned);
        Elem[result, e, esize] = Zeros();

Z[t] = result;