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FCVTZUN

Floating-point narrowing convert to interleaved unsigned integer, rounding toward zero

This instruction converts each floating-point element of the pair of source vectors to half-width unsigned integer nearer to zero, and places the two-way interleaved results in the corresponding half-width elements of the destination vector.

This instruction is unpredicated.

SVE2 class

(FEAT_SVE2p3 || FEAT_SME2p3)

313029282726252423222120191817161514131211109876543210
01100101size001101001101Zn0Zd
U

Encoding

FCVTZUN <Zd>.<T>, { <Zn1>.<Tb>-<Zn2>.<Tb> }

Decode

if !IsFeatureImplemented(FEAT_SVE2p3) && !IsFeatureImplemented(FEAT_SME2p3) then EndOfDecode(Decode_UNDEF); end; if size == '00' then EndOfDecode(Decode_UNDEF); end; let esize : integer{} = 8 << UInt(size); let n : integer = UInt(Zn::'0'); let d : integer = UInt(Zd); let unsigned : boolean = TRUE; let rounding : FPRounding = FPRounding_ZERO;

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 RESERVED
01 B
10 H
11 S
<Zn1>

Is the name of the first scalable vector register of the source multi-vector group, encoded as "Zn" times 2.

<Tb>

Is the size specifier, encoded in size:

size <Tb>
00 RESERVED
01 H
10 S
11 D
<Zn2>

Is the name of the second scalable vector register of the source multi-vector group, encoded as "Zn" times 2 plus 1.

Operation

CheckSVEEnabled(); let VL : integer{} = CurrentVL(); let elements : integer = VL DIV esize; let operand1 : bits(VL) = Z{}(n+0); let operand2 : bits(VL) = Z{}(n+1); var result : bits(VL); for e = 0 to elements-1 do let element1 : bits(esize) = operand1[e*:esize]; let element2 : bits(esize) = operand2[e*:esize]; result[(2*e + 0)*:(esize DIV 2)] = FPToFixed{esize DIV 2, esize}(element1, 0, unsigned, FPCR(), rounding); result[(2*e + 1)*:(esize DIV 2)] = FPToFixed{esize DIV 2, esize}(element2, 0, unsigned, FPCR(), rounding); end; Z{VL}(d) = result;


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