Refine wasm/aot function instance lookup (bytecodealliance#3865)

Sort the module instance's export functions with the function name,
and use binary search to lookup the wasm/aot function.

core/iwasm/aot/aot_runtime.c

@@ -1379,6 +1379,15 @@ init_func_type_indexes(AOTModuleInstance *module_inst, AOTModule *module,
     return true;
 }
 
+static int
+cmp_func_inst(const void *a, const void *b)
+{
+    const AOTFunctionInstance *func_inst1 = (const AOTFunctionInstance *)a;
+    const AOTFunctionInstance *func_inst2 = (const AOTFunctionInstance *)b;
+
+    return strcmp(func_inst1->func_name, func_inst2->func_name);
+}
+
 static bool
 create_export_funcs(AOTModuleInstance *module_inst, AOTModule *module,
                     char *error_buf, uint32 error_buf_size)
@@ -1419,6 +1428,9 @@ create_export_funcs(AOTModuleInstance *module_inst, AOTModule *module,
                 export_func++;
             }
         }
+
+        qsort(module_inst->export_functions, module_inst->export_func_count,
+              sizeof(AOTFunctionInstance), cmp_func_inst);
     }
 
     return true;
@@ -2206,14 +2218,12 @@ aot_deinstantiate(AOTModuleInstance *module_inst, bool is_sub_inst)
 AOTFunctionInstance *
 aot_lookup_function(const AOTModuleInstance *module_inst, const char *name)
 {
-    uint32 i;
     AOTFunctionInstance *export_funcs =
         (AOTFunctionInstance *)module_inst->export_functions;
+    AOTFunctionInstance key = { .func_name = (char *)name };
 
-    for (i = 0; i < module_inst->export_func_count; i++)
-        if (!strcmp(export_funcs[i].func_name, name))
-            return &export_funcs[i];
-    return NULL;
+    return bsearch(&key, export_funcs, module_inst->export_func_count,
+                   sizeof(AOTFunctionInstance), cmp_func_inst);
 }
 
 #ifdef OS_ENABLE_HW_BOUND_CHECK

core/iwasm/common/wasm_c_api.c

@@ -3391,8 +3391,7 @@ wasm_func_call(const wasm_func_t *func, const wasm_val_vec_t *params,
                 if (export->kind == EXPORT_KIND_FUNC) {
                     if (export->index == func->func_idx_rt) {
                         func_comm_rt =
-                            (AOTFunctionInstance *)inst_aot->export_functions
-                            + export_func_j;
+                            aot_lookup_function(inst_aot, export->name);
                         ((wasm_func_t *)func)->func_comm_rt = func_comm_rt;
                         break;
                     }

core/iwasm/common/wasm_runtime_common.c

@@ -3908,23 +3908,18 @@ wasm_runtime_is_wasi_mode(WASMModuleInstanceCommon *module_inst)
 WASMFunctionInstanceCommon *
 wasm_runtime_lookup_wasi_start_function(WASMModuleInstanceCommon *module_inst)
 {
-    uint32 i;
-
 #if WASM_ENABLE_INTERP != 0
     if (module_inst->module_type == Wasm_Module_Bytecode) {
         WASMModuleInstance *wasm_inst = (WASMModuleInstance *)module_inst;
-        WASMFunctionInstance *func;
-        for (i = 0; i < wasm_inst->export_func_count; i++) {
-            if (!strcmp(wasm_inst->export_functions[i].name, "_start")) {
-                func = wasm_inst->export_functions[i].function;
-                if (func->u.func->func_type->param_count != 0
-                    || func->u.func->func_type->result_count != 0) {
-                    LOG_ERROR("Lookup wasi _start function failed: "
-                              "invalid function type.\n");
-                    return NULL;
-                }
-                return (WASMFunctionInstanceCommon *)func;
+        WASMFunctionInstance *func = wasm_lookup_function(wasm_inst, "_start");
+        if (func) {
+            if (func->u.func->func_type->param_count != 0
+                || func->u.func->func_type->result_count != 0) {
+                LOG_ERROR("Lookup wasi _start function failed: "
+                          "invalid function type.\n");
+                return NULL;
             }
+            return (WASMFunctionInstanceCommon *)func;
         }
         return NULL;
     }
@@ -3933,19 +3928,15 @@ wasm_runtime_lookup_wasi_start_function(WASMModuleInstanceCommon *module_inst)
 #if WASM_ENABLE_AOT != 0
     if (module_inst->module_type == Wasm_Module_AoT) {
         AOTModuleInstance *aot_inst = (AOTModuleInstance *)module_inst;
-        AOTFunctionInstance *export_funcs =
-            (AOTFunctionInstance *)aot_inst->export_functions;
-        for (i = 0; i < aot_inst->export_func_count; i++) {
-            if (!strcmp(export_funcs[i].func_name, "_start")) {
-                AOTFuncType *func_type = export_funcs[i].u.func.func_type;
-                if (func_type->param_count != 0
-                    || func_type->result_count != 0) {
-                    LOG_ERROR("Lookup wasi _start function failed: "
-                              "invalid function type.\n");
-                    return NULL;
-                }
-                return (WASMFunctionInstanceCommon *)&export_funcs[i];
+        AOTFunctionInstance *func = aot_lookup_function(aot_inst, "_start");
+        if (func) {
+            AOTFuncType *func_type = func->u.func.func_type;
+            if (func_type->param_count != 0 || func_type->result_count != 0) {
+                LOG_ERROR("Lookup wasi _start function failed: "
+                          "invalid function type.\n");
+                return NULL;
             }
+            return func;
         }
         return NULL;
     }

core/iwasm/interpreter/wasm_runtime.c

@@ -1367,6 +1367,17 @@ export_functions_deinstantiate(WASMExportFuncInstance *functions)
         wasm_runtime_free(functions);
 }
 
+static int
+cmp_export_func_inst(const void *a, const void *b)
+{
+    const WASMExportFuncInstance *export_func1 =
+        (const WASMExportFuncInstance *)a;
+    const WASMExportFuncInstance *export_func2 =
+        (const WASMExportFuncInstance *)b;
+
+    return strcmp(export_func1->name, export_func2->name);
+}
+
 /**
  * Instantiate export functions in a module.
  */
@@ -1395,6 +1406,9 @@ export_functions_instantiate(const WASMModule *module,
         }
 
     bh_assert((uint32)(export_func - export_funcs) == export_func_count);
+
+    qsort(export_funcs, export_func_count, sizeof(WASMExportFuncInstance),
+          cmp_export_func_inst);
     return export_funcs;
 }
 
@@ -3420,11 +3434,17 @@ wasm_deinstantiate(WASMModuleInstance *module_inst, bool is_sub_inst)
 WASMFunctionInstance *
 wasm_lookup_function(const WASMModuleInstance *module_inst, const char *name)
 {
-    uint32 i;
-    for (i = 0; i < module_inst->export_func_count; i++)
-        if (!strcmp(module_inst->export_functions[i].name, name))
-            return module_inst->export_functions[i].function;
-    return NULL;
+    WASMExportFuncInstance key = { .name = (char *)name };
+    WASMExportFuncInstance *export_func_inst;
+
+    export_func_inst = bsearch(
+        &key, module_inst->export_functions, module_inst->export_func_count,
+        sizeof(WASMExportFuncInstance), cmp_export_func_inst);
+
+    if (!export_func_inst)
+        return NULL;
+
+    return export_func_inst->function;
 }
 
 WASMMemoryInstance *