Unsigned saturating extract narrow (bottom)
This instruction saturates the unsigned integer value in each source element to half the original source element width, and places the results in the even-numbered half-width destination elements, while setting the odd-numbered elements to zero.
| 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| 0 | 1 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | tszh | 1 | tszl | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 1 | 0 | Zn | Zd | |||||||||
| U | T | ||||||||||||||||||||||||||||||
if !IsFeatureImplemented(FEAT_SVE2) && !IsFeatureImplemented(FEAT_SME) then EndOfDecode(Decode_UNDEF); end; let tsize : bits(3) = tszh::tszl; if !(tsize IN {'001', '010', '100'}) then EndOfDecode(Decode_UNDEF); end; let esize : integer{} = 16 << HighestSetBitNZ(tsize); let n : integer = UInt(Zn); let d : integer = UInt(Zd);
| <Zd> |
Is the name of the destination scalable vector register, encoded in the "Zd" field. |
| <T> |
Is the size specifier,
encoded in
|
| <Zn> |
Is the name of the source scalable vector register, encoded in the "Zn" field. |
| <Tb> |
Is the size specifier,
encoded in
|
CheckSVEEnabled(); let VL : integer{} = CurrentVL(); let elements : integer = VL DIV esize; let operand1 : bits(VL) = Z{}(n); var result : bits(VL); let halfesize : integer{} = esize DIV 2; for e = 0 to elements-1 do let element1 : integer = UInt(operand1[e*:esize]); let res : bits(halfesize) = UnsignedSat{halfesize}(element1); result[(2*e + 0)*:halfesize] = res; result[(2*e + 1)*:halfesize] = Zeros{halfesize}; end; Z{VL}(d) = result;
2025-09_diff_tag 2025-11-28 16:29:05
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