convert: fix tensor sorting (#12015)

there's two bugs here.

1. the check for a layer id is incorrect and should be >= 0 since layer
   0 is valid
2. if both tensors have an layer identifier, it will only compare the
   layer id which will return 0 if the tensors are in the same layer.
   instead it should fallback to comparing the full tensor name

fs/ggml/ggml.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"io"
 	"log/slog"
+	"math"
 	"slices"
 	"strings"
 
@@ -276,7 +277,7 @@ type Tensor struct {
 
 func (t Tensor) block() (n int) {
 	if _, err := fmt.Sscanf(t.Name, "blk.%d.", &n); err != nil {
-		return -1
+		return math.MaxInt
 	}
 
 	return

fs/ggml/gguf.go

@@ -533,12 +533,15 @@ func WriteGGUF(f *os.File, kv KV, ts []*Tensor) error {
 		}
 	}
 
-	slices.SortStableFunc(ts, func(a, b *Tensor) int {
-		if i, j := a.block(), b.block(); i > 0 && j > 0 {
-			return cmp.Compare(i, j)
-		}
-		return cmp.Compare(a.Name, b.Name)
-	})
+	slices.SortStableFunc(
+		ts,
+		func(a, b *Tensor) int {
+			return cmp.Or(
+				cmp.Compare(a.block(), b.block()),
+				cmp.Compare(a.Name, b.Name),
+			)
+		},
+	)
 
 	var s uint64
 	for i := range ts {

fs/ggml/gguf_test.go

@@ -11,24 +11,24 @@ import (
 )
 
 func TestWriteGGUF(t *testing.T) {
-	r := rand.New(rand.NewPCG(0, 0))
+	b := bytes.NewBuffer(make([]byte, 2*3))
 	for range 8 {
 		t.Run("shuffle", func(t *testing.T) {
 			t.Parallel()
 
 			ts := []*Tensor{
-				{Name: "token_embd.weight", Shape: []uint64{2, 3}, WriterTo: bytes.NewBuffer(make([]byte, 2*3))},
-				{Name: "blk.0.attn_norm.weight", Shape: []uint64{2, 3}, WriterTo: bytes.NewBuffer(make([]byte, 2*3))},
-				{Name: "blk.1.attn_norm.weight", Shape: []uint64{2, 3}, WriterTo: bytes.NewBuffer(make([]byte, 2*3))},
-				{Name: "blk.2.attn_norm.weight", Shape: []uint64{2, 3}, WriterTo: bytes.NewBuffer(make([]byte, 2*3))},
-				{Name: "blk.3.attn_norm.weight", Shape: []uint64{2, 3}, WriterTo: bytes.NewBuffer(make([]byte, 2*3))},
-				{Name: "blk.4.attn_norm.weight", Shape: []uint64{2, 3}, WriterTo: bytes.NewBuffer(make([]byte, 2*3))},
-				{Name: "blk.5.attn_norm.weight", Shape: []uint64{2, 3}, WriterTo: bytes.NewBuffer(make([]byte, 2*3))},
-				{Name: "output_norm.weight", Shape: []uint64{3, 2}, WriterTo: bytes.NewBuffer(make([]byte, 3*2))},
-				{Name: "output.weight", Shape: []uint64{3, 2}, WriterTo: bytes.NewBuffer(make([]byte, 3*2))},
+				{Name: "token_embd.weight", Shape: []uint64{2, 3}, WriterTo: b},
+				{Name: "blk.0.ffn_norm.weight", Shape: []uint64{2, 3}, WriterTo: b},
+				{Name: "blk.0.attn_norm.weight", Shape: []uint64{2, 3}, WriterTo: b},
+				{Name: "blk.1.ffn_up.weight", Shape: []uint64{2, 3}, WriterTo: b},
+				{Name: "blk.2.ffn_norm.weight", Shape: []uint64{2, 3}, WriterTo: b},
+				{Name: "blk.1.ffn_down.weight", Shape: []uint64{2, 3}, WriterTo: b},
+				{Name: "blk.0.attn_k.weight", Shape: []uint64{2, 3}, WriterTo: b},
+				{Name: "output_norm.weight", Shape: []uint64{3, 2}, WriterTo: b},
+				{Name: "output.weight", Shape: []uint64{3, 2}, WriterTo: b},
 			}
 
-			r.Shuffle(len(ts), func(i, j int) {
+			rand.Shuffle(len(ts), func(i, j int) {
 				ts[i], ts[j] = ts[j], ts[i]
 			})
 
@@ -63,14 +63,14 @@ func TestWriteGGUF(t *testing.T) {
 			}
 
 			if diff := cmp.Diff(Tensors{
-				Offset: 608,
+				Offset: 592,
 				items: []*Tensor{
-					{Name: "blk.0.attn_norm.weight", Offset: 0, Shape: []uint64{2, 3}},
-					{Name: "blk.1.attn_norm.weight", Offset: 32, Shape: []uint64{2, 3}},
-					{Name: "blk.2.attn_norm.weight", Offset: 64, Shape: []uint64{2, 3}},
-					{Name: "blk.3.attn_norm.weight", Offset: 96, Shape: []uint64{2, 3}},
-					{Name: "blk.4.attn_norm.weight", Offset: 128, Shape: []uint64{2, 3}},
-					{Name: "blk.5.attn_norm.weight", Offset: 160, Shape: []uint64{2, 3}},
+					{Name: "blk.0.attn_k.weight", Offset: 0, Shape: []uint64{2, 3}},
+					{Name: "blk.0.attn_norm.weight", Offset: 32, Shape: []uint64{2, 3}},
+					{Name: "blk.0.ffn_norm.weight", Offset: 64, Shape: []uint64{2, 3}},
+					{Name: "blk.1.ffn_down.weight", Offset: 96, Shape: []uint64{2, 3}},
+					{Name: "blk.1.ffn_up.weight", Offset: 128, Shape: []uint64{2, 3}},
+					{Name: "blk.2.ffn_norm.weight", Offset: 160, Shape: []uint64{2, 3}},
 					{Name: "output.weight", Offset: 192, Shape: []uint64{3, 2}},
 					{Name: "output_norm.weight", Offset: 224, Shape: []uint64{3, 2}},
 					{Name: "token_embd.weight", Offset: 256, Shape: []uint64{2, 3}},