Signed saturating rounding doubling multiply high (unpredicated)
Multiply then double the corresponding signed elements of the first and second source vectors, and place the most significant rounded half of the result in the corresponding elements of the destination vector. Each result element is saturated to the N-bit element's signed integer range -2(N-1) to (2(N-1) )-1. This instruction is unpredicated.
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 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | size | 1 | Zm | 0 | 1 | 1 | 1 | 0 | 1 | Zn | Zd | |||||||||||||
R |
if !HaveSVE2() && !HaveSME() then UNDEFINED; constant integer esize = 8 << UInt(size); integer n = UInt(Zn); integer m = UInt(Zm); 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 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. |
CheckSVEEnabled(); constant integer VL = CurrentVL; constant integer elements = VL DIV esize; bits(VL) operand1 = Z[n, VL]; bits(VL) operand2 = Z[m, VL]; bits(VL) result; constant integer round_const = 1 << (esize - 1); for e = 0 to elements-1 integer element1 = SInt(Elem[operand1, e, esize]); integer element2 = SInt(Elem[operand2, e, esize]); integer res = 2 * element1 * element2; Elem[result, e, esize] = SignedSat((res + round_const) >> esize, esize); Z[d, VL] = result;
If FEAT_SVE2 is implemented or FEAT_SME is implemented, then when PSTATE.DIT is 1:
Internal version only: isa v33.53, AdvSIMD v29.11, pseudocode v2022-09_rel, sve v2022-09_rel ; Build timestamp: 2022-09-30T16:37
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