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Detect no matching elements, setting the condition flags.

This instruction compares each active 8-bit or 16-bit character in the first source vector with all of the characters in the corresponding 128-bit segment of the second source vector. Where the first source element detects no matching characters in the second segment it places true in the corresponding element of the destination predicate, otherwise 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.


NMATCH <Pd>.<T>, <Pg>/Z, <Zn>.<T>, <Zm>.<T>

if !HaveSVE2() then UNDEFINED;
if size == '1x' then UNDEFINED;
integer esize = 8 << UInt(size);
integer g = UInt(Pg);
integer d = UInt(Pd);
integer n = UInt(Zn);
integer m = UInt(Zm);

Assembler Symbols


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

<T> Is the size specifier, encoded in size<0>:
size<0> <T>
0 B
1 H

Is the name of the governing scalable predicate register P0-P7, encoded in the "Pg" field.


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


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


integer elements = VL DIV esize;
integer eltspersegment = 128 DIV esize;
bits(PL) mask = P[g];
bits(VL) operand1 = Z[n];
bits(VL) operand2 = Z[m];
bits(PL) result;

for e = 0 to elements-1
    if ElemP[mask, e, esize] == '1' then
        integer segmentbase = e - (e MOD eltspersegment);
        ElemP[result, e, esize] = '1';
        bits(esize) element1 = Elem[operand1, e, esize];
        for i = segmentbase to segmentbase + eltspersegment - 1
            bits(esize) element2 = Elem[operand2, i, esize];
            if element1 == element2 then
                ElemP[result, e, esize] = '0';
        ElemP[result, e, esize] = '0';

PSTATE.<N,Z,C,V> = PredTest(mask, result, esize);
P[d] = result;