FADDA

Floating-point add strictly-ordered reduction, accumulating in scalar

Floating-point add a SIMD&FP scalar source and all active lanes of the vector source and place the result destructively in the SIMD&FP scalar source register. Vector elements are processed strictly in order from low to high, with the scalar source providing the initial value. Inactive elements in the source vector are ignored.

313029282726252423222120191817161514131211109876543210
01100101size011000001PgZmVdn

FADDA <V><dn>, <Pg>, <V><dn>, <Zm>.<T>

if !HaveSVE() then UNDEFINED; if size == '00' then UNDEFINED; integer esize = 8 << UInt(size); integer g = UInt(Pg); integer dn = UInt(Vdn); integer m = UInt(Zm);

Assembler Symbols

<V>

Is a width specifier, encoded in size:

size <V>
00 RESERVED
01 H
10 S
11 D
<dn>

Is the number [0-31] of the source and destination SIMD&FP register, encoded in the "Vdn" field.

<Pg>

Is the name of the governing scalable predicate register P0-P7, encoded in the "Pg" field.

<Zm>

Is the name of the source scalable vector register, encoded in the "Zm" field.

<T>

Is the size specifier, encoded in size:

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

Operation

CheckNonStreamingSVEEnabled(); integer elements = VL DIV esize; bits(PL) mask = P[g]; bits(esize) operand1 = V[dn]; bits(VL) operand2 = if AnyActiveElement(mask, esize) then Z[m] else Zeros(); bits(esize) result = operand1; for e = 0 to elements-1 if ElemP[mask, e, esize] == '1' then bits(esize) element = Elem[operand2, e, esize]; result = FPAdd(result, element, FPCR[]); V[dn] = result;


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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