URSQRTE

Unsigned reciprocal square root estimate (predicated)

Find the approximate reciprocal square root of each active unsigned element of the source vector, and place the results in the corresponding elements of the destination vector. Inactive elements in the destination vector register remain unmodified.

313029282726252423222120191817161514131211109876543210
01000100size000001101PgZnZd
Q

URSQRTE <Zd>.S, <Pg>/M, <Zn>.S

if !HaveSVE2() && !HaveSME() then UNDEFINED; if size != '10' then UNDEFINED; constant integer esize = 32; integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Zd);

Assembler Symbols

<Zd>

Is the name of the destination scalable vector register, encoded in the "Zd" 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.

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); bits(VL) result = Z[d, VL]; for e = 0 to elements-1 if ActivePredicateElement(mask, e, esize) then bits(esize) element = Elem[operand, e, esize]; Elem[result, e, esize] = UnsignedRSqrtEstimate(element); Z[d, VL] = 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: aarchmrs v2023-12_rel, pseudocode v2023-12_rel, sve v2023-12_rel ; Build timestamp: 2023-12-15T16:46

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