Signed saturating extract narrow (bottom)
Saturate the signed integer value in each source element to half the original source element width, and place 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 | 0 | 0 | Zn | Zd | |||||||||
| U | T | ||||||||||||||||||||||||||||||
if !IsFeatureImplemented(FEAT_SVE2) && !IsFeatureImplemented(FEAT_SME) then EndOfDecode(Decode_UNDEF); constant bits(3) tsize = tszh:tszl; if !(tsize IN {'001', '010', '100'}) then EndOfDecode(Decode_UNDEF); constant integer esize = 16 << HighestSetBitNZ(tsize); constant integer n = UInt(Zn); constant integer d = 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(); constant integer VL = CurrentVL; constant integer PL = VL DIV 8; constant integer elements = VL DIV esize; constant bits(VL) operand1 = Z[n, VL]; bits(VL) result; constant integer halfesize = esize DIV 2; for e = 0 to elements-1 constant integer element1 = SInt(Elem[operand1, e, esize]); constant bits(halfesize) res = SignedSat(element1, halfesize); Elem[result, 2*e + 0, halfesize] = res; Elem[result, 2*e + 1, halfesize] = Zeros(halfesize); Z[d, VL] = result;
Internal version only: aarchmrs v2024-12_rel, pseudocode v2024-12_rel ; Build timestamp: 2024-12-15T22:18
Copyright © 2010-2024 Arm Limited or its affiliates. All rights reserved. This document is Non-Confidential.