Floatingpoint complex multiplyadd by indexed values with rotate
Multiply the duplicated real components for rotations 0 and 180, or imaginary components for rotations 90 and 270, of the floatingpoint complex numbers in each 128bit segment of the first source vector by the specified complex number in the corresponding the second source vector segment rotated by 0, 90, 180 or 270 degrees in the direction from the positive real axis towards the positive imaginary axis, when considered in polar representation.
Then destructively add the products to the corresponding components of the complex numbers in the addend and destination vector, without intermediate rounding.
These transformations permit the creation of a variety of multiplyadd and multiplysubtract operations on complex numbers by combining two of these instructions with the same vector operands but with rotations that are 90 degrees apart.
Each complex number is represented in a vector register as an even/odd pair of elements with the real part in the evennumbered element and the imaginary part in the oddnumbered element.
The complex numbers within the second source vector are specified using an immediate index which selects the same complex number position within each 128bit vector segment. The index range is from 0 to one less than the number of complex numbers per 128bit segment, encoded in 1 to 2 bits depending on the size of the complex number. This instruction is unpredicated.
It has encodings from 2 classes: Halfprecision and Singleprecision
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  1  0  0  1  0  0  1  0  1  i2  Zm  0  0  0  1  rot  Zn  Zda  
size<1>  size<0> 
if !IsFeatureImplemented(FEAT_SVE) && !IsFeatureImplemented(FEAT_SME) then UNDEFINED; constant integer esize = 16; constant integer index = UInt(i2); constant integer n = UInt(Zn); constant integer m = UInt(Zm); constant integer da = UInt(Zda); constant integer sel_a = UInt(rot<0>); constant integer sel_b = UInt(NOT(rot<0>)); constant boolean neg_i = (rot<1> == '1'); constant boolean neg_r = (rot<0> != rot<1>);
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  1  0  0  1  0  0  1  1  1  i1  Zm  0  0  0  1  rot  Zn  Zda  
size<1>  size<0> 
if !IsFeatureImplemented(FEAT_SVE) && !IsFeatureImplemented(FEAT_SME) then UNDEFINED; constant integer esize = 32; constant integer index = UInt(i1); constant integer n = UInt(Zn); constant integer m = UInt(Zm); constant integer da = UInt(Zda); constant integer sel_a = UInt(rot<0>); constant integer sel_b = UInt(NOT(rot<0>)); constant boolean neg_i = (rot<1> == '1'); constant boolean neg_r = (rot<0> != rot<1>);
<Zda> 
Is the name of the third source and destination scalable vector register, encoded in the "Zda" field. 
<Zn> 
Is the name of the first source scalable vector register, encoded in the "Zn" field. 
<const> 
Is the const specifier,
encoded in

CheckSVEEnabled(); constant integer VL = CurrentVL; constant integer PL = VL DIV 8; constant integer pairs = VL DIV (2 * esize); constant integer pairspersegment = 128 DIV (2 * esize); constant bits(VL) operand1 = Z[n, VL]; constant bits(VL) operand2 = Z[m, VL]; constant bits(VL) operand3 = Z[da, VL]; bits(VL) result; for p = 0 to pairs1 segmentbase = p  (p MOD pairspersegment); s = segmentbase + index; addend_r = Elem[operand3, 2 * p + 0, esize]; addend_i = Elem[operand3, 2 * p + 1, esize]; elt1_a = Elem[operand1, 2 * p + sel_a, esize]; elt2_a = Elem[operand2, 2 * s + sel_a, esize]; elt2_b = Elem[operand2, 2 * s + sel_b, esize]; if neg_r then elt2_a = FPNeg(elt2_a, FPCR); if neg_i then elt2_b = FPNeg(elt2_b, FPCR); addend_r = FPMulAdd(addend_r, elt1_a, elt2_a, FPCR); addend_i = FPMulAdd(addend_i, elt1_a, elt2_b, FPCR); Elem[result, 2 * p + 0, esize] = addend_r; Elem[result, 2 * p + 1, esize] = addend_i; Z[da, VL] = 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:
Internal version only: aarchmrs v202403_relA, pseudocode v202403_rel, sve v202403_rel ; Build timestamp: 20240326T09:45
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