FMAXNMP

Floating-point maximum number pairwise

Compute the maximum value of each pair of adjacent floating-point elements within each source vector, and interleave the results from corresponding lanes. The interleaved result values are destructively placed in the first source vector. NaNs are handled according to the IEEE 754-2008 standard. If one vector element is numeric and the other is a quiet NaN, the result is the numerical value.

313029282726252423222120191817161514131211109876543210
01100100size010100100PgZmZdn

FMAXNMP <Zdn>.<T>, <Pg>/M, <Zdn>.<T>, <Zm>.<T>

if !HaveSVE2() && !HaveSME() then UNDEFINED; if size == '00' then UNDEFINED; integer esize = 8 << UInt(size); integer g = UInt(Pg); integer m = UInt(Zm); integer dn = UInt(Zdn);

Assembler Symbols

<Zdn>

Is the name of the first source and destination scalable vector register, encoded in the "Zdn" field.

<T>

Is the size specifier, encoded in size:

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.

Operation

CheckSVEEnabled(); integer elements = VL DIV esize; bits(PL) mask = P[g]; bits(VL) operand1 = Z[dn]; bits(VL) operand2 = if AnyActiveElement(mask, esize) then Z[m] else Zeros(); bits(VL) result = Z[dn]; bits(esize) element1; bits(esize) element2; for e = 0 to elements-1 if ElemP[mask, e, esize] == '1' then if IsEven(e) then element1 = Elem[operand1, e + 0, esize]; element2 = Elem[operand1, e + 1, esize]; else element1 = Elem[operand2, e - 1, esize]; element2 = Elem[operand2, e + 0, esize]; Elem[result, e, esize] = FPMaxNum(element1, element2, FPCR[]); Z[dn] = result;

Operational information

This instruction might be immediately preceded in program order by a MOVPRFX instruction. The MOVPRFX instruction must conform to all of the following requirements, otherwise the behavior of the MOVPRFX and this instruction is unpredictable:


Internal version only: isa v33.11seprel, AdvSIMD v29.05, pseudocode v2021-09_rel, sve v2021-09_rc3d ; Build timestamp: 2021-10-06T11:41

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