bf16

convert/reader.go

@@ -31,8 +31,9 @@ func (t tensorBase) Shape() []uint64 {
 }
 
 const (
-	tensorKindF32 uint32 = iota
-	tensorKindF16
+	tensorKindFP32 uint32 = iota
+	tensorKindFP16
+	tensorKindBF16 = 30
 )
 
 func (t tensorBase) Kind() uint32 {
@@ -43,16 +44,16 @@ func (t tensorBase) Kind() uint32 {
 		t.name == "v.pre_tile_position_embd.weight" ||
 		t.name == "v.post_tile_position_embd.weight" {
 		// these tensors are always F32
-		return 0
+		return tensorKindFP32
 	}
 
 	switch len(t.shape) {
 	case 0:
 		panic("invalid tensor shape")
 	case 1:
-		return tensorKindF32
+		return tensorKindFP32
 	default:
-		return tensorKindF16
+		return tensorKindBF16
 	}
 }
 

convert/reader_safetensors.go

@@ -162,15 +162,18 @@ func (st safetensor) WriteTo(w io.Writer) (int64, error) {
 	}
 
 	switch st.Kind() {
-	case tensorKindF32:
+	case tensorKindFP32:
 		return 0, binary.Write(w, binary.LittleEndian, f32s)
-	case tensorKindF16:
+	case tensorKindFP16:
 		f16s := make([]uint16, len(f32s))
 		for i := range f32s {
 			f16s[i] = float16.Fromfloat32(f32s[i]).Bits()
 		}
 
 		return 0, binary.Write(w, binary.LittleEndian, f16s)
+	case tensorKindBF16:
+		u8s := bfloat16.EncodeFloat32(f32s)
+		return 0, binary.Write(w, binary.LittleEndian, u8s)
 	default:
 		return 0, fmt.Errorf("unknown storage type: %d", st.Kind())
 	}