BRKAS

Break after first true condition, setting the condition flags

Sets destination predicate elements up to and including the first active and true source element to true, then sets subsequent elements to false. Inactive elements in the destination predicate register are set to zero. Sets the First (N), None (Z), !Last (C) condition flags based on the predicate result, and the V flag to zero.

313029282726252423222120191817161514131211109876543210
001001010101000001Pg0Pn0Pd
BSM

BRKAS <Pd>.B, <Pg>/Z, <Pn>.B

if !HaveSVE() && !HaveSME() then UNDEFINED; integer esize = 8; integer g = UInt(Pg); integer n = UInt(Pn); integer d = UInt(Pd); boolean merging = FALSE; boolean setflags = TRUE;

Assembler Symbols

<Pd>

Is the name of the destination scalable predicate register, encoded in the "Pd" field.

<Pg>

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

<Pn>

Is the name of the source scalable predicate register, encoded in the "Pn" field.

Operation

CheckSVEEnabled(); integer elements = VL DIV esize; bits(PL) mask = P[g]; bits(PL) operand = P[n]; bits(PL) operand2 = P[d]; boolean break = FALSE; bits(PL) result; for e = 0 to elements-1 boolean element = ElemP[operand, e, esize] == '1'; if ElemP[mask, e, esize] == '1' then ElemP[result, e, esize] = if !break then '1' else '0'; break = break || element; elsif merging then ElemP[result, e, esize] = ElemP[operand2, e, esize]; else ElemP[result, e, esize] = '0'; if setflags then PSTATE.<N,Z,C,V> = PredTest(mask, result, esize); P[d] = result;

Operational information

If FEAT_SME is implemented and the PE is in Streaming SVE mode, then any subsequent instruction which is dependent on the NZCV condition flags written by this instruction might be significantly delayed.


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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