Floating-point multiply by indexed element
This instruction multiplies all floating-point elements within each 128-bit segment of the first source vector by the specified element in the corresponding second source vector segment. The results are placed in the corresponding elements of the destination vector.
The elements within the second source vector are specified using an immediate index that selects the same element position within each 128-bit vector segment. The index range is from 0 to one less than the number of elements per 128-bit segment. This instruction is unpredicated.
It has encodings from 3 classes: Half-precision , Single-precision and Double-precision
| 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 | 1 | 0 | 0 | 1 | 0 | 0 | 0 | i3h | 1 | i3l | Zm | 0 | 0 | 1 | 0 | 0 | 0 | Zn | Zd | |||||||||||
| o2 | |||||||||||||||||||||||||||||||
if !IsFeatureImplemented(FEAT_SVE) && !IsFeatureImplemented(FEAT_SME) then EndOfDecode(Decode_UNDEF); end; let esize : integer{} = 16; let index : integer = UInt(i3h::i3l); let n : integer = UInt(Zn); let m : integer = UInt(Zm); let d : integer = UInt(Zd);
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| 0 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 1 | 0 | 1 | i2 | Zm | 0 | 0 | 1 | 0 | 0 | 0 | Zn | Zd | |||||||||||
| size | o2 | ||||||||||||||||||||||||||||||
if !IsFeatureImplemented(FEAT_SVE) && !IsFeatureImplemented(FEAT_SME) then EndOfDecode(Decode_UNDEF); end; let esize : integer{} = 32; let index : integer = UInt(i2); let n : integer = UInt(Zn); let m : integer = UInt(Zm); let d : integer = UInt(Zd);
| 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 | 1 | 0 | 0 | 1 | 0 | 0 | 1 | 1 | 1 | i1 | Zm | 0 | 0 | 1 | 0 | 0 | 0 | Zn | Zd | |||||||||||
| size | o2 | ||||||||||||||||||||||||||||||
if !IsFeatureImplemented(FEAT_SVE) && !IsFeatureImplemented(FEAT_SME) then EndOfDecode(Decode_UNDEF); end; let esize : integer{} = 64; let index : integer = UInt(i1); let n : integer = UInt(Zn); let m : integer = UInt(Zm); let d : integer = UInt(Zd);
| <Zd> |
Is the name of the destination scalable vector register, encoded in the "Zd" field. |
| <Zn> |
Is the name of the first source scalable vector register, encoded in the "Zn" field. |
CheckSVEEnabled(); let VL : integer{} = CurrentVL(); let elements : integer = VL DIV esize; let eltspersegment : integer = 128 DIV esize; let op1 : bits(VL) = Z{}(n); let op2 : bits(VL) = Z{}(m); var result : bits(VL); for e = 0 to elements-1 do let segmentbase : integer = e - (e MOD eltspersegment); let s : integer = segmentbase + index; let elem2 : bits(esize) = op2[s*:esize]; let elem1 : bits(esize) = op1[e*:esize]; result[e*:esize] = FPMul{esize}(elem1, elem2, FPCR()); end; Z{VL}(d) = result;
2026-03_rel 2026-03-26 20:48:11
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