Signed Add and Accumulate Long Pairwise. This instruction adds pairs of adjacent signed integer values from the vector in the source SIMD&FP register and accumulates the results into the vector elements of the destination SIMD&FP register. The destination vector elements are twice as long as the source vector elements.
Depending on the settings in the CPACR_EL1, CPTR_EL2, and CPTR_EL3 registers, and the current Security state and Exception level, an attempt to execute the instruction might be trapped.
31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
0 | Q | 0 | 0 | 1 | 1 | 1 | 0 | size | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 1 | 0 | Rn | Rd | |||||||||
U | op |
integer d = UInt(Rd); integer n = UInt(Rn); if size == '11' then UNDEFINED; integer esize = 8 << UInt(size); integer datasize = if Q == '1' then 128 else 64; integer elements = datasize DIV (2*esize); boolean acc = (op == '1'); boolean unsigned = (U == '1');
<Vd> |
Is the name of the SIMD&FP destination register, encoded in the "Rd" field. |
<Ta> |
Is an arrangement specifier,
encoded in
|
<Vn> |
Is the name of the SIMD&FP source register, encoded in the "Rn" field. |
<Tb> |
Is an arrangement specifier,
encoded in
|
CheckFPAdvSIMDEnabled64(); bits(datasize) operand = V[n]; bits(datasize) result; bits(2*esize) sum; integer op1; integer op2; if acc then result = V[d]; for e = 0 to elements-1 op1 = Int(Elem[operand, 2*e+0, esize], unsigned); op2 = Int(Elem[operand, 2*e+1, esize], unsigned); sum = (op1 + op2)<2*esize-1:0>; if acc then Elem[result, e, 2*esize] = Elem[result, e, 2*esize] + sum; else Elem[result, e, 2*esize] = sum; V[d] = result;
If PSTATE.DIT is 1:
Internal version only: isa v33.11seprel, AdvSIMD v29.05, pseudocode v2021-09_rel, sve v2021-09_rc3d ; Build timestamp: 2021-10-06T11:41
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