BF1CVT, BF2CVT

Multi-vector 8-bit floating-point convert to BFloat16

This instruction converts each 8-bit floating-point element of the source vector to BFloat16 while downscaling the value, and places the results in the corresponding 16-bit elements of the destination vectors. BF1CVT scales the values by 2-UInt(FPMR.LSCALE[5:0]). BF2CVT scales the values by 2-UInt(FPMR.LSCALE2[5:0]). The 8-bit floating-point encoding format for BF1CVT is selected by FPMR.F8S1. The 8-bit floating-point encoding format for BF2CVT is selected by FPMR.F8S2.

This instruction is unpredicated.

It has encodings from 2 classes: BF1CVT and BF2CVT

BF1CVT
(FEAT_SME2 && FEAT_FP8)

313029282726252423222120191817161514131211109876543210
1100000101100110111000ZnZd0
opcL

Encoding

BF1CVT { <Zd1>.H-<Zd2>.H }, <Zn>.B

Decode for this encoding

if !IsFeatureImplemented(FEAT_SME2) || !IsFeatureImplemented(FEAT_FP8) then EndOfDecode(Decode_UNDEF); end; let n : integer = UInt(Zn); let d : integer = UInt(Zd:: '0'); let issrc2 : boolean = FALSE;

BF2CVT
(FEAT_SME2 && FEAT_FP8)

313029282726252423222120191817161514131211109876543210
1100000111100110111000ZnZd0
opcL

Encoding

BF2CVT { <Zd1>.H-<Zd2>.H }, <Zn>.B

Decode for this encoding

if !IsFeatureImplemented(FEAT_SME2) || !IsFeatureImplemented(FEAT_FP8) then EndOfDecode(Decode_UNDEF); end; let n : integer = UInt(Zn); let d : integer = UInt(Zd:: '0'); let issrc2 : boolean = TRUE;

Assembler Symbols

<Zd1>

Is the name of the first scalable vector register of the destination multi-vector group, encoded as "Zd" times 2.

<Zd2>

Is the name of the second scalable vector register of the destination multi-vector group, encoded as "Zd" times 2 plus 1.

<Zn>

Is the name of the source scalable vector register, encoded in the "Zn" field.


2025-09_diff_tag 2025-11-28 16:29:05

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