BFADD (unpredicated)

BFloat16 add vectors (unpredicated)

Add all BFloat16 elements of the second source vector to corresponding elements of the first source vector and place the results in the corresponding elements of the destination vector.

This instruction follows SVE2 non-widening BFloat16 numerical behaviors.

This instruction is unpredicated.

ID_AA64ZFR0_EL1.B16B16 indicates whether this instruction is implemented.

Encoding: SVE2

Variants: FEAT_SVE_B16B16 (ARMv9.4)

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	1	0	0	0						0	0	0	0	0	0
								size			Zm								opc			Zn					Zd

BFADD <Zd>.H, <Zn>.H, <Zm>.H

Decoding algorithm

if !IsFeatureImplemented(FEAT_SVE_B16B16) then EndOfDecode(Decode_UNDEF);
constant integer n = UInt(Zn);
constant integer m = UInt(Zm);
constant integer d = UInt(Zd);

Operation

if IsFeatureImplemented(FEAT_SME2) then CheckSVEEnabled(); else CheckNonStreamingSVEEnabled();
constant integer VL = CurrentVL;
constant integer elements = VL DIV 16;
constant bits(VL) operand1 = Z[n, VL];
constant bits(VL) operand2 = Z[m, VL];
bits(VL) result;

for e = 0 to elements-1
    constant bits(16) element1 = Elem[operand1, e, 16];
    constant bits(16) element2 = Elem[operand2, e, 16];
    Elem[result, e, 16] = BFAdd(element1, element2, FPCR);

Z[d, VL] = result;

Explanations

<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.
<Zm>: Is the name of the second source scalable vector register, encoded in the "Zm" field.