gguf : add tensor shape accessor (ggml-org#24405)

* gguf : add tensor shape accessors

* gguf : return tensor shape as const int64_t *

* gguf : remove n_dims accessor, keep only gguf_get_tensor_ne

Author: QuintinShaw

ggml/include/gguf.h

@@ -125,12 +125,13 @@ extern "C" {
     // get ith C string from array with given key_id
     GGML_API const char * gguf_get_arr_str (const struct gguf_context * ctx, int64_t key_id, size_t i);
 
-    GGML_API int64_t        gguf_get_n_tensors    (const struct gguf_context * ctx);
-    GGML_API int64_t        gguf_find_tensor      (const struct gguf_context * ctx, const char * name); // returns -1 if the tensor is not found
-    GGML_API size_t         gguf_get_tensor_offset(const struct gguf_context * ctx, int64_t tensor_id);
-    GGML_API const char *   gguf_get_tensor_name  (const struct gguf_context * ctx, int64_t tensor_id);
-    GGML_API enum ggml_type gguf_get_tensor_type  (const struct gguf_context * ctx, int64_t tensor_id);
-    GGML_API size_t         gguf_get_tensor_size  (const struct gguf_context * ctx, int64_t tensor_id);
+    GGML_API int64_t         gguf_get_n_tensors    (const struct gguf_context * ctx);
+    GGML_API int64_t         gguf_find_tensor      (const struct gguf_context * ctx, const char * name); // returns -1 if the tensor is not found
+    GGML_API size_t          gguf_get_tensor_offset(const struct gguf_context * ctx, int64_t tensor_id);
+    GGML_API const char *    gguf_get_tensor_name  (const struct gguf_context * ctx, int64_t tensor_id);
+    GGML_API const int64_t * gguf_get_tensor_ne    (const struct gguf_context * ctx, int64_t tensor_id); // returns ne, an array of GGML_MAX_DIMS elements; ne[dim] is 1 for dim >= n_dims
+    GGML_API enum ggml_type  gguf_get_tensor_type  (const struct gguf_context * ctx, int64_t tensor_id);
+    GGML_API size_t          gguf_get_tensor_size  (const struct gguf_context * ctx, int64_t tensor_id);
 
     // removes key if it exists, returns id that the key had prior to removal (-1 if it didn't exist)
     GGML_API int64_t gguf_remove_key(struct gguf_context * ctx, const char * key);

ggml/src/gguf.cpp

@@ -1186,6 +1186,11 @@ const char * gguf_get_tensor_name(const struct gguf_context * ctx, int64_t tenso
     return ctx->info[tensor_id].t.name;
 }
 
+const int64_t * gguf_get_tensor_ne(const struct gguf_context * ctx, int64_t tensor_id) {
+    GGML_ASSERT(tensor_id >= 0 && tensor_id < gguf_get_n_tensors(ctx));
+    return ctx->info[tensor_id].t.ne;
+}
+
 enum ggml_type gguf_get_tensor_type(const struct gguf_context * ctx, int64_t tensor_id) {
     GGML_ASSERT(tensor_id >= 0 && tensor_id < gguf_get_n_tensors(ctx));
     return ctx->info[tensor_id].t.type;

tests/test-gguf.cpp

@@ -662,6 +662,13 @@ static bool handcrafted_check_tensors(const gguf_context * gguf_ctx, const unsig
             if (gguf_get_tensor_type(gguf_ctx, id) != type) {
                 ok = false;
             }
+
+            const int64_t * ne = gguf_get_tensor_ne(gguf_ctx, id);
+            for (int j = 0; j < GGML_MAX_DIMS; ++j) {
+                if (ne[j] != shape[j]) {
+                    ok = false;
+                }
+            }
         } else {
             ok = false;
             continue;