Break after first true condition
This instruction sets the 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 remain unmodified or are set to zero, depending on whether merging or zeroing predication is selected. This instruction does not set the condition flags.
| 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| 0 | 0 | 1 | 0 | 0 | 1 | 0 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 1 | Pg | 0 | Pn | M | Pd | |||||||||
| B | S | ||||||||||||||||||||||||||||||
if !IsFeatureImplemented(FEAT_SVE) && !IsFeatureImplemented(FEAT_SME) then EndOfDecode(Decode_UNDEF); end; let esize : integer{} = 8; let g : integer = UInt(Pg); let n : integer = UInt(Pn); let d : integer = UInt(Pd); let merging : boolean = (M == '1'); let setflags : boolean = FALSE;
| <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. |
| <ZM> |
Is the predication qualifier,
encoded in
|
| <Pn> |
Is the name of the source scalable predicate register, encoded in the "Pn" field. |
CheckSVEEnabled(); let VL : integer{} = CurrentVL(); let PL : integer{} = VL DIV 8; let elements : integer = VL DIV esize; let mask : bits(PL) = P{}(g); let operand : bits(PL) = P{}(n); let operand2 : bits(PL) = if merging then P{PL}(d) else Zeros{PL}; var break : boolean = FALSE; var result : bits(PL); let psize : integer{} = esize DIV 8; for e = 0 to elements-1 do let element : boolean = ActivePredicateElement{PL}(operand, e, esize); if ActivePredicateElement{PL}(mask, e, esize) then let pbit : bit = if !break then '1' else '0'; result[e*:psize] = ZeroExtend{psize}(pbit); break = break || element; elsif merging then let pbit : bit = PredicateElement{PL}(operand2, e, esize); result[e*:psize] = ZeroExtend{psize}(pbit); else result[e*:psize] = ZeroExtend{psize}('0'); end; end; if setflags then PSTATE.[N,Z,C,V] = PredTest{PL}(mask, result, esize); end; P{PL}(d) = result;
2026-03_rel 2026-03-26 20:48:11
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