SEL (vectors)

Conditionally select elements from two vectors.

Read active elements from the first source vector and inactive elements from the second source vector and place in the corresponding elements of the destination vector.

This instruction is used by the alias MOV (vector, predicated) . See Alias Conditions below for details of when the alias is preferred.

313029282726252423222120191817161514131211109876543210
00000101size1Zm11PgZnZd

SVE

SEL <Zd>.<T>, <Pg>, <Zn>.<T>, <Zm>.<T>

if !HaveSVE() then UNDEFINED; integer esize = 8 << UInt(size); integer g = UInt(Pg); integer n = UInt(Zn); integer m = UInt(Zm); integer d = UInt(Zd);

Assembler Symbols

<Zd>

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

<T> Is the size specifier, encoded in size:
size <T>
00 B
01 H
10 S
11 D
<Pg>

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

<Zn>

Is the name of the first source scalable vector register, encoded in the "Zn" field.

<Zm>

Is the name of the second source scalable vector register, encoded in the "Zm" field.

Alias Conditions

AliasIs preferred when
MOV (vector, predicated)Zd == Zm

Operation

CheckSVEEnabled(); integer elements = VL DIV esize; bits(PL) mask = P[g]; bits(VL) operand1 = Z[n]; bits(VL) operand2 = Z[m]; bits(VL) result; for e = 0 to elements-1 bits(esize) element1 = Elem[operand1, e, esize]; bits(esize) element2 = Elem[operand2, e, esize]; if ElemP[mask, e, esize] == '1' then Elem[result, e, esize] = element1; else Elem[result, e, esize] = element2; Z[d] = result;


Release: 00rel5-manual

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