BFMLA (multiple vectors)

Multi-vector BFloat16 floating-point fused multiply-add

Multiply the corresponding BFloat16 floating-point elements of the two or four first and second source vectors and destructively add without intermediate rounding to the corresponding elements of the ZA single-vector groups.

The single-vector group within each half of or each quarter of the ZA array is selected by the sum of the vector select register and offset , modulo half or quarter the number of ZA array vectors.

The vector group symbol, VGx2 or VGx4, indicates that the ZA operand consists of two or four ZA single-vector groups respectively. The vector group symbol is preferred for disassembly, but optional in assembler source code.

This instruction follows SME2 ZA-targeting non-widening BFloat16 numerical behaviors.

This instruction is unpredicated.

ID_AA64SMFR0_EL1.B16B16 indicates whether this instruction is implemented.

It has encodings from 2 classes: Two ZA single-vectors and Four ZA single-vectors

Two ZA single-vectors
(FEAT_SME_B16B16)

Decode for this encoding

if !IsFeatureImplemented(FEAT_SME_B16B16) then EndOfDecode(Decode_UNDEF); constant integer v = UInt('010':Rv); constant integer n = UInt(Zn:'0'); constant integer m = UInt(Zm:'0'); constant integer offset = UInt(off3); constant integer nreg = 2;

Four ZA single-vectors
(FEAT_SME_B16B16)

Decode for this encoding

if !IsFeatureImplemented(FEAT_SME_B16B16) then EndOfDecode(Decode_UNDEF); constant integer v = UInt('010':Rv); constant integer n = UInt(Zn:'00'); constant integer m = UInt(Zm:'00'); constant integer offset = UInt(off3); constant integer nreg = 4;