FMAXNMQV
Floating-point maximum number recursive reduction of quadword vector segments
Floating-point maximum number of the same element numbers from each 128-bit source vector segment using a recursive pairwise reduction, placing each result into the corresponding element number of the 128-bit SIMD&FP destination register. Inactive elements in the source vector are treated as the default NaN.
Regardless of the value of FPCR.AH, the behavior is as follows:
Negative zero compares less than positive zero.
If one value is numeric and the other is a quiet NaN, the result is the numeric value.
When FPCR.DN is 0, if either value is a signaling NaN or if both values are NaNs, the result is a quiet NaN.
When FPCR.DN is 1, if either value is a signaling NaN or if both values are NaNs, the result is Default NaN.
Green
True
0
1
1
0
0
1
0
0
0
1
0
1
0
0
1
0
1
FMAXNMQV <Vd>.<T>, <Pg>, <Zn>.<Tb>
if !IsFeatureImplemented(FEAT_SVE2p1) && !IsFeatureImplemented(FEAT_SME2p1) then UNDEFINED;
if size == '00' then UNDEFINED;
constant integer esize = 8 << UInt(size);
constant integer g = UInt(Pg);
constant integer n = UInt(Zn);
constant integer d = UInt(Vd);
<Vd>
Is the name of the destination SIMD&FP register, encoded in the "Vd" field.
<T>
Is an arrangement specifier,
size
<T>
00
RESERVED
01
8H
10
4S
11
2D
<Pg>
Is the name of the governing scalable predicate register P0-P7, encoded in the "Pg" field.
<Zn>
Is the name of the source scalable vector register, encoded in the "Zn" field.
<Tb>
Is the size specifier,
size
<Tb>
00
RESERVED
01
H
10
S
11
D
CheckSVEEnabled();
constant integer VL = CurrentVL;
constant integer PL = VL DIV 8;
constant integer segments = VL DIV 128;
constant integer elempersegment = 128 DIV esize;
constant integer segbits = segments*esize;
constant bits(PL) mask = P[g, PL];
constant bits(VL) operand = if AnyActiveElement(mask, esize) then Z[n, VL] else Zeros(VL);
constant bits(esize) identity = FPDefaultNaN(FPCR, esize);
bits(128) result = Zeros(128);
for e = 0 to elempersegment-1
bits(segbits) stmp;
for s = 0 to segments-1
if ActivePredicateElement(mask, s * elempersegment + e, esize) then
Elem[stmp, s, esize] = Elem[operand, s * elempersegment + e, esize];
else
Elem[stmp, s, esize] = identity;
Elem[result, e, esize] = FPReduce(ReduceOp_FMAXNUM, stmp, esize, FPCR);
V[d, 128] = result;