Signed multiply returning high half (unpredicated)
This instruction performs a widening multiplication of signed integer values of all elements of the first source vector by the corresponding elements of the second source vector and places the high half of the result in the corresponding elements of the destination vector. 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 | 0 | 1 | 0 | Zn | Zd | |||||||||||||
| U | |||||||||||||||||||||||||||||||
if !IsFeatureImplemented(FEAT_SVE2) && !IsFeatureImplemented(FEAT_SME) then EndOfDecode(Decode_UNDEF); end; let esize : integer{} = 8 << UInt(size); let n : integer = UInt(Zn); let m : integer = UInt(Zm); let d : integer = UInt(Zd); let unsigned : boolean = FALSE;
| <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(); let VL : integer{} = CurrentVL(); let elements : integer = VL DIV esize; let operand1 : bits(VL) = Z{}(n); let operand2 : bits(VL) = Z{}(m); var result : bits(VL); for e = 0 to elements-1 do let op1elt : bits(esize) = operand1[e*:esize]; let op2elt : bits(esize) = operand2[e*:esize]; let element1 : integer = if unsigned then UInt(op1elt) else SInt(op1elt); let element2 : integer = if unsigned then UInt(op2elt) else SInt(op2elt); let product : integer = (element1 * element2) >> esize; result[e*:esize] = product[esize-1:0]; end; Z{VL}(d) = result;
This instruction is a data-independent-time instruction as described in About PSTATE.DIT.
2025-12_rel 2025-12-10 16:41:45
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