FABD
Floating-point absolute difference (predicated)
Compute the absolute difference of active floating-point elements of the second source vector and corresponding floating-point elements of the first source vector and destructively place the result in the corresponding elements of the first source vector. Inactive elements in the destination vector register remain unmodified.
Green
True
True
True
0
1
1
0
0
1
0
1
0
0
1
0
0
0
1
0
0
FABD <Zdn>.<T>, <Pg>/M, <Zdn>.<T>, <Zm>.<T>
if !IsFeatureImplemented(FEAT_SVE) && !IsFeatureImplemented(FEAT_SME) then UNDEFINED;
if size == '00' then UNDEFINED;
constant integer esize = 8 << UInt(size);
constant integer g = UInt(Pg);
constant integer dn = UInt(Zdn);
constant integer m = UInt(Zm);
<Zdn>
Is the name of the first source and destination scalable vector register, encoded in the "Zdn" field.
<T>
Is the size specifier,
size
<T>
00
RESERVED
01
H
10
S
11
D
<Pg>
Is the name of the governing scalable predicate register P0-P7, encoded in the "Pg" field.
<Zm>
Is the name of the second source scalable vector register, encoded in the "Zm" field.
CheckSVEEnabled();
constant integer VL = CurrentVL;
constant integer PL = VL DIV 8;
constant integer elements = VL DIV esize;
constant bits(PL) mask = P[g, PL];
constant bits(VL) operand1 = Z[dn, VL];
constant bits(VL) operand2 = if AnyActiveElement(mask, esize) then Z[m, VL] else Zeros(VL);
bits(VL) result;
for e = 0 to elements-1
constant bits(esize) element1 = Elem[operand1, e, esize];
if ActivePredicateElement(mask, e, esize) then
constant bits(esize) element2 = Elem[operand2, e, esize];
Elem[result, e, esize] = FPAbs(FPSub(element1, element2, FPCR), FPCR);
else
Elem[result, e, esize] = element1;
Z[dn, VL] = result;