Saturating complex integer add
This instruction adds the real and imaginary components of the integral complex numbers from the first source vector to the complex numbers from the second source vector that have first been rotated by 90 or 270 degrees in the direction from the positive real axis towards the positive imaginary axis, when considered in polar representation, equivalent to multiplying the complex numbers in the second source vector by ±j beforehand. The results are destructively placed in the corresponding elements of the first source vector. Each result element is saturated to the N-bit element's signed integer range -2(N-1) to (2(N-1))-1. This instruction is unpredicated.
Each complex number is represented in a vector register as an even/odd pair of elements with the real part in the even-numbered element and the imaginary part in the odd-numbered element.
| 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 | 1 | 0 | 0 | 0 | 1 | 0 | 1 | size | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 0 | 1 | 1 | rot | Zm | Zdn | |||||||||
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if !IsFeatureImplemented(FEAT_SVE2) && !IsFeatureImplemented(FEAT_SME) then EndOfDecode(Decode_UNDEF); end; let esize : integer{} = 8 << UInt(size); let m : integer = UInt(Zm); let dn : integer = UInt(Zdn); let sub_i : boolean = (rot == '0'); let sub_r : boolean = (rot == '1');
| <Zdn> |
Is the name of the first source and destination scalable vector register, encoded in the "Zdn" field. |
| <T> |
Is the size specifier,
encoded in
|
| <Zm> |
Is the name of the second source scalable vector register, encoded in the "Zm" field. |
| <const> |
Is the const specifier,
encoded in
|
CheckSVEEnabled(); let VL : integer{} = CurrentVL(); let pairs : integer = VL DIV (2 * esize); let operand1 : bits(VL) = Z{}(dn); let operand2 : bits(VL) = Z{}(m); var result : bits(VL); for p = 0 to pairs-1 do var acc_r : integer = SInt(operand1[(2 * p + 0)*:esize]); var acc_i : integer = SInt(operand1[(2 * p + 1)*:esize]); let elt2_r : integer = SInt(operand2[(2 * p + 0)*:esize]); let elt2_i : integer = SInt(operand2[(2 * p + 1)*:esize]); if sub_i then acc_r = acc_r - elt2_i; acc_i = acc_i + elt2_r; end; if sub_r then acc_r = acc_r + elt2_i; acc_i = acc_i - elt2_r; end; result[(2 * p + 0)*:esize] = SignedSat{esize}(acc_r); result[(2 * p + 1)*:esize] = SignedSat{esize}(acc_i); end; Z{VL}(dn) = result;
This instruction might be immediately preceded in program order by a MOVPRFX instruction. The MOVPRFX must conform to all of the following requirements, otherwise the behavior of the MOVPRFX and this instruction is CONSTRAINED UNPREDICTABLE:
2026-03_rel 2026-03-26 20:48:11
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