UMAXV

Unsigned maximum reduction to scalar

Unsigned maximum horizontally across all lanes of a vector, and place the result in the SIMD&FP scalar destination register. Inactive elements in the source vector are treated as zero.

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00000100size001001001PgZnVd
U

UMAXV <V><d>, <Pg>, <Zn>.<T>

if !HaveSVE() && !HaveSME() then UNDEFINED; constant integer esize = 8 << UInt(size); integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Vd); boolean unsigned = TRUE;

Assembler Symbols

<V>

Is a width specifier, encoded in size:

size <V>
00 B
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, encoded in size:

size <T>
00 B
01 H
10 S
11 D

Operation

CheckSVEEnabled(); constant integer VL = CurrentVL; constant integer PL = VL DIV 8; constant integer elements = VL DIV esize; bits(PL) mask = P[g, PL]; bits(VL) operand = if AnyActiveElement(mask, esize) then Z[n, VL] else Zeros(VL); integer maximum = if unsigned then 0 else -(2^(esize-1)); for e = 0 to elements-1 if ActivePredicateElement(mask, e, esize) then integer element = Int(Elem[operand, e, esize], unsigned); maximum = Max(maximum, element); V[d, esize] = maximum<esize-1:0>;

Operational information

If FEAT_SVE2 is implemented or FEAT_SME is implemented, then if PSTATE.DIT is 1:


Internal version only: aarchmrs v2023-12_rel, pseudocode v2023-12_rel, sve v2023-12_rel ; Build timestamp: 2023-12-15T16:46

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