drop float16 dependency

goos: darwin
goarch: arm64
pkg: github.com/ollama/ollama/convert/float16
cpu: Apple M3 Max
BenchmarkFloat16/x448/float16-16                     159           7398462 ns/op
BenchmarkFloat16/simple-16                           512           2327098 ns/op
PASS
ok      github.com/ollama/ollama/convert/float16        2.553s

convert/float16/float16_test.go

@@ -0,0 +1,75 @@
+package float16
+
+import (
+	"math"
+	"math/rand/v2"
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+)
+
+func TestFloat16(t *testing.T) {
+	cases := []struct {
+		name  string
+		input uint16
+		want  uint32
+	}{
+		// Zero cases
+		{"positive zero", 0x0000, 0x0},
+		{"negative zero", 0x8000, 0x80000000},
+
+		// Normal numbers
+		{"one", 0x3C00, 0x3F800000},
+		{"negative one", 0xBC00, 0xBF800000},
+		{"two", 0x4000, 0x40000000},
+		{"half", 0x3800, 0x3F000000},
+		{"max normal", 0x7BFF, 0x477fe000},
+		{"min positive normal", 0x0400, 0x38800000},
+
+		// Infinity cases
+		{"positive infinity", 0x7C00, 0x7F800000},
+		{"negative infinity", 0xFC00, 0xFF800000},
+
+		// NaN cases
+		{"NaN", 0x7C01, 0x7f802000},
+		{"NaN with payload", 0x7E00, 0x7FC00000},
+
+		// Subnormal cases
+		{"min positive subnormal", 0x0001, 0x33800000},
+		{"max subnormal", 0x03FF, 0x387fc000},
+
+		// Common values
+		{"pi approximation", 0x4248, 0x40490000},
+		{"e approximation", 0x416F, 0x402de000},
+	}
+
+	for _, tt := range cases {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+
+			t.Run("Float32s", func(t *testing.T) {
+				got := Float32s([]uint16{tt.input})[0]
+				if diff := cmp.Diff(tt.want, math.Float32bits(got)); diff != "" {
+					t.Errorf("Float32s mismatch (-want +got):\n%s", diff)
+				}
+			})
+
+			t.Run("FromFloat32s", func(t *testing.T) {
+				got := FromFloat32s([]float32{math.Float32frombits(tt.want)})
+				if diff := cmp.Diff([]uint16{tt.input}, got); diff != "" {
+					t.Errorf("FromFloat32s mismatch (-want +got):\n%s", diff)
+				}
+			})
+		})
+	}
+}
+
+func BenchmarkFloat16(b *testing.B) {
+	f32s := make([]float32, 1_000_000)
+	for i := range f32s {
+		f32s[i] = rand.Float32()
+	}
+	for b.Loop() {
+		Float32s(FromFloat32s(f32s))
+	}
+}