Refactor WASI-NN to simplify the support for multiple frameworks (#1834)

- Reorganize the library structure
- Use the latest version of `wasi-nn` wit (Oct 25, 2022):
    https://github.com/WebAssembly/wasi-nn/blob/0f77c48ec195748990ff67928a4b3eef5f16c2de/wasi-nn.wit.md
- Split logic that converts WASM structs to native structs in a separate file
- Simplify addition of new frameworks

Author: tonibofarull

build-scripts/runtime_lib.cmake

@@ -96,9 +96,13 @@ if (WAMR_BUILD_LIB_PTHREAD_SEMAPHORE EQUAL 1)
 endif ()
 
 if (WAMR_BUILD_WASI_NN EQUAL 1)
-    execute_process(COMMAND ${WAMR_ROOT_DIR}/core/deps/install_tensorflow.sh
-                    RESULT_VARIABLE TENSORFLOW_RESULT
-    )
+    if (NOT EXISTS "${WAMR_ROOT_DIR}/core/deps/tensorflow-src")
+        execute_process(COMMAND ${WAMR_ROOT_DIR}/core/deps/install_tensorflow.sh
+                        RESULT_VARIABLE TENSORFLOW_RESULT
+        )
+    else ()
+        message("Tensorflow is already downloaded.")
+    endif()
     set(TENSORFLOW_SOURCE_DIR "${WAMR_ROOT_DIR}/core/deps/tensorflow-src")
     include_directories (${CMAKE_CURRENT_BINARY_DIR}/flatbuffers/include)
     include_directories (${TENSORFLOW_SOURCE_DIR})

core/iwasm/aot/aot_runtime.c

@@ -1083,6 +1083,17 @@ aot_instantiate(AOTModule *module, bool is_sub_inst, uint32 stack_size,
     }
 #endif
 
+#if WASM_ENABLE_WASI_NN != 0
+    if (!is_sub_inst) {
+        if (!(((AOTModuleInstanceExtra *)module_inst->e)->wasi_nn_ctx =
+                  wasi_nn_initialize())) {
+            set_error_buf(error_buf, error_buf_size,
+                          "wasi nn initialization failed");
+            goto fail;
+        }
+    }
+#endif
+
     /* Initialize the thread related data */
     if (stack_size == 0)
         stack_size = DEFAULT_WASM_STACK_SIZE;
@@ -1194,6 +1205,15 @@ aot_deinstantiate(AOTModuleInstance *module_inst, bool is_sub_inst)
         wasm_runtime_free(
             ((AOTModuleInstanceExtra *)module_inst->e)->c_api_func_imports);
 
+#if WASM_ENABLE_WASI_NN != 0
+    if (!is_sub_inst) {
+        WASINNContext *wasi_nn_ctx =
+            ((AOTModuleInstanceExtra *)module_inst->e)->wasi_nn_ctx;
+        if (wasi_nn_ctx)
+            wasi_nn_destroy(wasi_nn_ctx);
+    }
+#endif
+
     wasm_runtime_free(module_inst);
 }
 

core/iwasm/aot/aot_runtime.h

@@ -11,6 +11,10 @@
 #include "../interpreter/wasm_runtime.h"
 #include "../compilation/aot.h"
 
+#if WASM_ENABLE_WASI_NN != 0
+#include "../libraries/wasi-nn/src/wasi_nn_private.h"
+#endif
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -75,6 +79,9 @@ typedef struct AOTFunctionInstance {
 
 typedef struct AOTModuleInstanceExtra {
     CApiFuncImport *c_api_func_imports;
+#if WASM_ENABLE_WASI_NN != 0
+    WASINNContext *wasi_nn_ctx;
+#endif
 } AOTModuleInstanceExtra;
 
 #if defined(OS_ENABLE_HW_BOUND_CHECK) && defined(BH_PLATFORM_WINDOWS)

core/iwasm/interpreter/wasm_runtime.c

@@ -1803,6 +1803,16 @@ wasm_instantiate(WASMModule *module, bool is_sub_inst, uint32 stack_size,
     }
 #endif
 
+#if WASM_ENABLE_WASI_NN != 0
+    if (!is_sub_inst) {
+        if (!(module_inst->e->wasi_nn_ctx = wasi_nn_initialize())) {
+            set_error_buf(error_buf, error_buf_size,
+                          "wasi nn initialization failed");
+            goto fail;
+        }
+    }
+#endif
+
 #if WASM_ENABLE_DEBUG_INTERP != 0                         \
     || (WASM_ENABLE_FAST_JIT != 0 && WASM_ENABLE_JIT != 0 \
         && WASM_ENABLE_LAZY_JIT != 0)
@@ -1984,6 +1994,14 @@ wasm_deinstantiate(WASMModuleInstance *module_inst, bool is_sub_inst)
     if (module_inst->e->c_api_func_imports)
         wasm_runtime_free(module_inst->e->c_api_func_imports);
 
+#if WASM_ENABLE_WASI_NN != 0
+    if (!is_sub_inst) {
+        WASINNContext *wasi_nn_ctx = module_inst->e->wasi_nn_ctx;
+        if (wasi_nn_ctx)
+            wasi_nn_destroy(wasi_nn_ctx);
+    }
+#endif
+
     wasm_runtime_free(module_inst);
 }
 

core/iwasm/interpreter/wasm_runtime.h

@@ -11,6 +11,10 @@
 #include "../common/wasm_runtime_common.h"
 #include "../common/wasm_exec_env.h"
 
+#if WASM_ENABLE_WASI_NN != 0
+#include "../libraries/wasi-nn/src/wasi_nn_private.h"
+#endif
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -242,6 +246,10 @@ typedef struct WASMModuleInstanceExtra {
         && WASM_ENABLE_LAZY_JIT != 0)
     WASMModuleInstance *next;
 #endif
+
+#if WASM_ENABLE_WASI_NN != 0
+    WASINNContext *wasi_nn_ctx;
+#endif
 } WASMModuleInstanceExtra;
 
 struct AOTFuncPerfProfInfo;

core/iwasm/libraries/wasi-nn/.dockerignore

@@ -37,7 +37,11 @@ Tests: passed!
 
 ## What is missing
 
-* Only 1 model at a time is supported.
+Supported:
+
+* Only 1 WASM app at a time.
+* Only 1 model at a time.
     * `graph` and `graph-execution-context` are ignored.
-* Only `tensorflow` (lite) is supported.
-* Only `cpu` is supported.
+* Graph encoding: `tensorflowlite`.
+* Execution target: `cpu`.
+* Tensor type: `fp32`.

core/iwasm/libraries/wasi-nn/README.md

@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2019 Intel Corporation.  All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+ */
+
+#ifndef WASI_NN_LOGGER_H
+#define WASI_NN_LOGGER_H
+
+#include <stdio.h>
+#include <string.h>
+
+#define __FILENAME__ \
+    (strrchr(__FILE__, '/') ? strrchr(__FILE__, '/') + 1 : __FILE__)
+
+/* Disable a level by removing the define */
+#define ENABLE_ERR_LOG
+#define ENABLE_WARN_LOG
+#define ENABLE_DBG_LOG
+#define ENABLE_INFO_LOG
+
+// Definition of the levels
+#ifdef ENABLE_ERR_LOG
+#define NN_ERR_PRINTF(fmt, ...)                                        \
+    do {                                                               \
+        printf("[%s:%d] " fmt, __FILENAME__, __LINE__, ##__VA_ARGS__); \
+        printf("\n");                                                  \
+        fflush(stdout);                                                \
+    } while (0)
+#else
+#define NN_ERR_PRINTF(fmt, ...)
+#endif
+#ifdef ENABLE_WARN_LOG
+#define NN_WARN_PRINTF(fmt, ...)                                       \
+    do {                                                               \
+        printf("[%s:%d] " fmt, __FILENAME__, __LINE__, ##__VA_ARGS__); \
+        printf("\n");                                                  \
+        fflush(stdout);                                                \
+    } while (0)
+#else
+#define NN_WARN_PRINTF(fmt, ...)
+#endif
+#ifdef ENABLE_DBG_LOG
+#define NN_DBG_PRINTF(fmt, ...)                                        \
+    do {                                                               \
+        printf("[%s:%d] " fmt, __FILENAME__, __LINE__, ##__VA_ARGS__); \
+        printf("\n");                                                  \
+        fflush(stdout);                                                \
+    } while (0)
+#else
+#define NN_DBG_PRINTF(fmt, ...)
+#endif
+#ifdef ENABLE_INFO_LOG
+#define NN_INFO_PRINTF(fmt, ...)                                       \
+    do {                                                               \
+        printf("[%s:%d] " fmt, __FILENAME__, __LINE__, ##__VA_ARGS__); \
+        printf("\n");                                                  \
+        fflush(stdout);                                                \
+    } while (0)
+#else
+#define NN_INFO_PRINTF(fmt, ...)
+#endif
+
+#endif