EORS

Bitwise exclusive OR predicates, setting the condition flags

Bitwise exclusive OR active elements of the second source predicate with corresponding elements of the first source predicate and place the results in the corresponding elements of the destination predicate. 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.

This instruction is used by the alias NOTS.

313029282726252423222120191817161514131211109876543210
001001010100Pm01Pg1Pn0Pd
S

EORS <Pd>.B, <Pg>/Z, <Pn>.B, <Pm>.B

if !HaveSVE() && !HaveSME() then UNDEFINED; integer esize = 8; integer g = UInt(Pg); integer n = UInt(Pn); integer m = UInt(Pm); integer d = UInt(Pd); 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 first source scalable predicate register, encoded in the "Pn" field.

<Pm>

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

Alias Conditions

AliasIs preferred when
NOTSPm == Pg

Operation

CheckSVEEnabled(); integer elements = VL DIV esize; bits(PL) mask = P[g]; bits(PL) operand1 = P[n]; bits(PL) operand2 = P[m]; bits(PL) result; for e = 0 to elements-1 bit element1 = ElemP[operand1, e, esize]; bit element2 = ElemP[operand2, e, esize]; if ElemP[mask, e, esize] == '1' then ElemP[result, e, esize] = element1 EOR element2; 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_SVE2 is enabled or FEAT_SME is enabled, then when PSTATE.DIT is 1:

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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