FDOT (2-way, vectors, FP8 to FP16)

8-bit floating-point dot product to half-precision

This instruction calculates the fused sum-of-products of a pair of 8-bit floating-point values held in each 16-bit element of the first source and second source vectors. The half-precision sum-of-products are scaled by 2-UInt(FPMR.LSCALE[3:0]), before being destructively added without intermediate rounding to the corresponding half-precision elements of the destination vector.

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

This instruction is unpredicated.

SVE2
((FEAT_SVE2 && FEAT_FP8DOT2) || FEAT_SSVE_FP8DOT2)

313029282726252423222120191817161514131211109876543210
01100100001Zm100001ZnZda
opo2

Encoding

FDOT <Zda>.H, <Zn>.B, <Zm>.B

Decode for this encoding

if !HaveSVE2FP8DOT2() then EndOfDecode(Decode_UNDEF); end; let n : integer = UInt(Zn); let m : integer = UInt(Zm); let da : integer = UInt(Zda);

Assembler Symbols

<Zda>

Is the name of the third source and destination scalable vector register, encoded in the "Zda" field.

<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.

Operational information

This instruction might be immediately preceded in program order by a MOVPRFX instruction. The MOVPRFX must conform to all of the following requirements, otherwise the behavior of the MOVPRFX and this instruction is CONSTRAINED UNPREDICTABLE:


2025-12_rel 2025-12-10 16:41:45

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