FDOT (8-bit floating-point to single-precision, by element)

8-bit floating-point dot product to single-precision (vector, by element)

This instruction calculates the fused sum-of-products of a group of four 8-bit floating-point values held in each 32-bit element of the first source vector and a group of four 8-bit floating-point values in an indexed 32-bit element of the second source vector. The single-precision sum-of-products are scaled by 2^{-UInt(FPMR.LSCALE)}, before being destructively added without intermediate rounding to the corresponding single-precision elements of the destination vector.

The 8-bit floating-point groups within the second source vector are specified using an immediate index.

The 8-bit floating-point encoding format for the elements of the first source vector is selected by FPMR.F8S1. The 8-bit floating-point encoding format for the elements of the second source vector is selected by FPMR.F8S2.

Advanced SIMD
(FEAT_FP8DOT4)

Decode for this encoding

if !IsFeatureImplemented(FEAT_FP8DOT4) then EndOfDecode(Decode_UNDEF); end; let n : integer = UInt(Rn); let d : integer = UInt(Rd); let m : integer = UInt(M::Rm); let i : integer = UInt(H::L); let datasize : integer{} = if Q == '1' then 128 else 64; let esize : integer{} = 32; let elements : integer = datasize DIV esize;