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LD1D (scalar plus scalar)

Contiguous load doublewords to vector (scalar index).

Contiguous load of doublewords to elements of a vector register from the memory address generated by a 64-bit scalar base and scalar index which is multiplied by 8 and added to the base address. After each element access the index value is incremented, but the index register is not updated. Inactive elements will not read Device memory or signal a fault, and are set to zero in the destination vector.

313029282726252423222120191817161514131211109876543210
10100101111Rm010PgRnZt

SVE

LD1D { <Zt>.D }, <Pg>/Z, [<Xn|SP>, <Xm>, LSL #3]

if !HaveSVE() then UNDEFINED;
if Rm == '11111' then UNDEFINED;
integer t = UInt(Zt);
integer n = UInt(Rn);
integer m = UInt(Rm);
integer g = UInt(Pg);
integer esize = 64;
integer msize = 64;
boolean unsigned = TRUE;

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.

<Xn|SP>

Is the 64-bit name of the general-purpose base register or stack pointer, encoded in the "Rn" field.

<Xm>

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

Operation

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

if HaveMTEExt() then SetNotTagCheckedInstruction(FALSE);

if n == 31 then
    CheckSPAlignment();
    base = SP[];
else
    base = X[n];

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

Z[t] = result;
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