PTRUE (predicate as counter)

Initialize predicate-as-counter to all active

This instruction sets the destination predicate as all Active elements, using the predicate-as-counter encoding.

SVE2
(FEAT_SME2 || FEAT_SVE2p1)

313029282726252423222120191817161514131211109876543210
00100101size1000000111100000010PNd

Encoding

PTRUE <PNd>.<T>

Decode for this encoding

if !IsFeatureImplemented(FEAT_SME2) && !IsFeatureImplemented(FEAT_SVE2p1) then EndOfDecode(Decode_UNDEF); end; let esize : integer{} = 8 << UInt(size); let d : integer = UInt('1'::PNd);

Assembler Symbols

<PNd>

Is the name of the destination scalable predicate register PN8-PN15, with predicate-as-counter encoding, encoded in the "PNd" field.

<T>

Is the size specifier, encoded in size:

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

Operation

if IsFeatureImplemented(FEAT_SVE2p1) then CheckSVEEnabled(); else CheckStreamingSVEEnabled(); end; let VL : integer{} = CurrentVL(); let PL : integer{} = VL DIV 8; let elements : integer = VL DIV esize; let result : bits(PL) = EncodePredCount{}(esize, elements, elements, FALSE); P{PL}(d) = result;


2026-03_rel 2026-03-26 20:48:11

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