Support graph encoding backend auto-detection in wasi-nn.

Author: TE-7000026184

core/iwasm/libraries/wasi-nn/src/wasi_nn.c

@@ -491,20 +491,50 @@ wasi_nn_load(wasm_exec_env_t exec_env, graph_builder_array_wasm *builder,
         goto fail;
     }
 
-    res = ensure_backend(instance, encoding, wasi_nn_ctx);
-    if (res != success)
-        goto fail;
+    if (encoding == autodetect) {
+        for (graph_encoding e = openvino; e <= unknown_backend; e++) {
+            if (wasi_nn_ctx->is_backend_ctx_initialized) {
+                call_wasi_nn_func(wasi_nn_ctx->backend, deinit, res,
+                                  wasi_nn_ctx->backend_ctx);
+            }
+
+            res = ensure_backend(instance, e, wasi_nn_ctx);
+            if (res != success) {
+                NN_ERR_PRINTF("continue trying the next");
+                continue;
+            }
+
+            call_wasi_nn_func(wasi_nn_ctx->backend, load, res,
+                              wasi_nn_ctx->backend_ctx, &builder_native, e,
+                              target, g);
+            if (res != success) {
+                NN_ERR_PRINTF("continue trying the next");
+                continue;
+            }
+
+            break;
+        }
+    }
+    else {
+        res = ensure_backend(instance, encoding, wasi_nn_ctx);
+        if (res != success)
+            goto fail;
 
-    call_wasi_nn_func(wasi_nn_ctx->backend, load, res, wasi_nn_ctx->backend_ctx,
-                      &builder_native, encoding, target, g);
-    if (res != success)
-        goto fail;
+        call_wasi_nn_func(wasi_nn_ctx->backend, load, res,
+                          wasi_nn_ctx->backend_ctx, &builder_native, encoding,
+                          target, g);
+        if (res != success)
+            goto fail;
+    }
 
 fail:
     // XXX: Free intermediate structure pointers
-    if (builder_native.buf)
+    if (builder_native.buf) {
         wasm_runtime_free(builder_native.buf);
-    unlock_ctx(wasi_nn_ctx);
+    }
+    if (wasi_nn_ctx) {
+        unlock_ctx(wasi_nn_ctx);
+    }
 
     return res;
 }
@@ -565,17 +595,29 @@ wasi_nn_load_by_name(wasm_exec_env_t exec_env, char *name, uint32_t name_len,
         goto fail;
     }
 
-    res = ensure_backend(instance, autodetect, wasi_nn_ctx);
-    if (res != success)
-        goto fail;
+    for (graph_encoding e = openvino; e <= unknown_backend; e++) {
+        if (wasi_nn_ctx->is_backend_ctx_initialized) {
+            call_wasi_nn_func(wasi_nn_ctx->backend, deinit, res,
+                              wasi_nn_ctx->backend_ctx);
+        }
 
-    call_wasi_nn_func(wasi_nn_ctx->backend, load_by_name, res,
-                      wasi_nn_ctx->backend_ctx, nul_terminated_name, name_len,
-                      g);
-    if (res != success)
-        goto fail;
+        res = ensure_backend(instance, e, wasi_nn_ctx);
+        if (res != success) {
+            NN_ERR_PRINTF("continue trying the next");
+            continue;
+        }
+
+        call_wasi_nn_func(wasi_nn_ctx->backend, load_by_name, res,
+                          wasi_nn_ctx->backend_ctx, nul_terminated_name,
+                          name_len, g);
+        if (res != success) {
+            NN_ERR_PRINTF("continue trying the next");
+            continue;
+        }
+
+        break;
+    }
 
-    res = success;
 fail:
     if (nul_terminated_name != NULL) {
         wasm_runtime_free(nul_terminated_name);
@@ -627,18 +669,29 @@ wasi_nn_load_by_name_with_config(wasm_exec_env_t exec_env, char *name,
         goto fail;
     }
 
-    res = ensure_backend(instance, autodetect, wasi_nn_ctx);
-    if (res != success)
-        goto fail;
-    ;
+    for (graph_encoding e = openvino; e <= unknown_backend; e++) {
+        if (wasi_nn_ctx->is_backend_ctx_initialized) {
+            call_wasi_nn_func(wasi_nn_ctx->backend, deinit, res,
+                              wasi_nn_ctx->backend_ctx);
+        }
 
-    call_wasi_nn_func(wasi_nn_ctx->backend, load_by_name_with_config, res,
-                      wasi_nn_ctx->backend_ctx, nul_terminated_name, name_len,
-                      nul_terminated_config, config_len, g);
-    if (res != success)
-        goto fail;
+        res = ensure_backend(instance, e, wasi_nn_ctx);
+        if (res != success) {
+            NN_ERR_PRINTF("continue trying the next");
+            continue;
+        }
+
+        call_wasi_nn_func(wasi_nn_ctx->backend, load_by_name_with_config, res,
+                          wasi_nn_ctx->backend_ctx, nul_terminated_name,
+                          name_len, nul_terminated_config, config_len, g);
+        if (res != success) {
+            NN_ERR_PRINTF("continue trying the next");
+            continue;
+        }
+
+        break;
+    }
 
-    res = success;
 fail:
     if (nul_terminated_name != NULL) {
         wasm_runtime_free(nul_terminated_name);