FMAXV
Floating-point maximum recursive reduction to scalar
Floating-point maximum horizontally over all lanes of a vector using a recursive pairwise reduction, and place the result in the SIMD&FP scalar destination register. Inactive elements in the source vector are treated as -Infinity.
When FPCR.AH is 0, the behavior is as follows:
Negative zero compares less than positive zero.
When FPCR.DN is 0, if either value is a NaN, the result is a quiet NaN.
When FPCR.DN is 1, if either value is a NaN, the result is Default NaN.
When FPCR.AH is 1, the behavior is as follows:
If both values are zeros, regardless of the sign of either zero, the result is the second value.
If either value is a NaN, regardless of the value of FPCR.DN, the result is the second value.
Green
True
0
1
1
0
0
1
0
1
0
0
0
1
1
0
0
0
1
FMAXV <V><d>, <Pg>, <Zn>.<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 n = UInt(Zn);
constant integer d = UInt(Vd);
<V>
Is a width specifier,
size
<V>
00
RESERVED
01
H
10
S
11
D
<d>
Is the number [0-31] of the destination SIMD&FP register, encoded in the "Vd" field.
<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.
<T>
Is the size specifier,
size
<T>
00
RESERVED
01
H
10
S
11
D
CheckSVEEnabled();
constant integer VL = CurrentVL;
constant integer PL = VL DIV 8;
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 = FPInfinity('1', esize);
V[d, esize] = FPReducePredicated(ReduceOp_FMAX, operand, mask, identity, FPCR);