instantiate.js

// @ts-check
import { SwiftRuntime } from "./runtime.js";

export const MODULE_PATH = "@PACKAGE_TO_JS_MODULE_PATH@";
/* #if USE_SHARED_MEMORY */
export const MEMORY_TYPE = {
    // @ts-expect-error Substituted by PackageToJS preprocessor
    initial: import.meta.PACKAGE_TO_JS_MEMORY_INITIAL,
    // @ts-expect-error Substituted by PackageToJS preprocessor
    maximum: import.meta.PACKAGE_TO_JS_MEMORY_MAXIMUM,
    // @ts-expect-error Substituted by PackageToJS preprocessor
    shared: import.meta.PACKAGE_TO_JS_MEMORY_SHARED,
};
/* #endif */

/* #if HAS_BRIDGE */
// @ts-expect-error Substituted by PackageToJS preprocessor
import { createInstantiator } from "./bridge-js.js";
/* #else */
/**
 * @param {import('./instantiate.d').InstantiateOptions} options
 * @param {any} swift
 */
async function createInstantiator(options, swift) {
    return {
        /**
         * @param {WebAssembly.Imports} importObject
         * @param {unknown} importsContext
         */
        addImports: (importObject, importsContext) => {
            // Provide a default implementation for BridgeJS functions that are not
            // used at runtime without BridgeJS but required to instantiate the module.
            const unexpectedBjsCall = () => {
                throw new Error("Unexpected call to BridgeJS function");
            };
            importObject["bjs"] = {
                swift_js_return_string: unexpectedBjsCall,
                swift_js_init_memory: unexpectedBjsCall,
                swift_js_make_js_string: unexpectedBjsCall,
                swift_js_init_memory_with_result: unexpectedBjsCall,
                swift_js_throw: unexpectedBjsCall,
                swift_js_retain: unexpectedBjsCall,
                swift_js_release: unexpectedBjsCall,
                swift_js_push_i32: unexpectedBjsCall,
                swift_js_push_f32: unexpectedBjsCall,
                swift_js_push_f64: unexpectedBjsCall,
                swift_js_push_string: unexpectedBjsCall,
                swift_js_pop_i32: unexpectedBjsCall,
                swift_js_pop_f32: unexpectedBjsCall,
                swift_js_pop_f64: unexpectedBjsCall,
                swift_js_return_optional_bool: unexpectedBjsCall,
                swift_js_return_optional_int: unexpectedBjsCall,
                swift_js_return_optional_string: unexpectedBjsCall,
                swift_js_return_optional_double: unexpectedBjsCall,
                swift_js_return_optional_float: unexpectedBjsCall,
                swift_js_return_optional_heap_object: unexpectedBjsCall,
                swift_js_return_optional_object: unexpectedBjsCall,
                swift_js_get_optional_int_presence: unexpectedBjsCall,
                swift_js_get_optional_int_value: unexpectedBjsCall,
                swift_js_get_optional_string: unexpectedBjsCall,
                swift_js_get_optional_float_presence: unexpectedBjsCall,
                swift_js_get_optional_float_value: unexpectedBjsCall,
                swift_js_get_optional_double_presence: unexpectedBjsCall,
                swift_js_get_optional_double_value: unexpectedBjsCall,
                swift_js_get_optional_heap_object_pointer: unexpectedBjsCall,
                swift_js_push_pointer: unexpectedBjsCall,
                swift_js_pop_pointer: unexpectedBjsCall,
                swift_js_push_i64: unexpectedBjsCall,
                swift_js_pop_i64: unexpectedBjsCall,
                swift_js_closure_unregister: unexpectedBjsCall,
            };
        },
        /** @param {WebAssembly.Instance} instance */
        setInstance: (instance) => {},
        /** @param {WebAssembly.Instance} instance */
        createExports: (instance) => {
            return {};
        },
    };
}
/* #endif */

/** @type {import('./instantiate.d').instantiate} */
export async function instantiate(options) {
    const result = await _instantiate(options);
    /* #if IS_WASI */
    options.wasi.initialize(result.instance);
    /* #endif */
    result.swift.main();
    return result;
}

/** @type {import('./instantiate.d').instantiateForThread} */
export async function instantiateForThread(tid, startArg, options) {
    const result = await _instantiate(options);
    /* #if IS_WASI */
    options.wasi.setInstance(result.instance);
    /* #endif */
    result.swift.startThread(tid, startArg);
    return result;
}

/** @type {import('./instantiate.d').instantiate} */
async function _instantiate(options) {
    const _WebAssembly = options.WebAssembly || WebAssembly;
    const moduleSource = options.module;
    /* #if IS_WASI */
    const { wasi } = options;
    /* #endif */
    const swift = new SwiftRuntime({
        /* #if USE_SHARED_MEMORY */
        sharedMemory: true,
        threadChannel: options.threadChannel,
        /* #endif */
    });
    const instantiator = await createInstantiator(options, swift);

    /** @type {WebAssembly.Imports} */
    const importObject = {
        javascript_kit: swift.wasmImports,
        /* #if IS_WASI */
        wasi_snapshot_preview1: wasi.wasiImport,
        /* #if USE_SHARED_MEMORY */
        env: {
            memory: options.memory,
        },
        wasi: {
            "thread-spawn": (startArg) => {
                return options.threadChannel.spawnThread(
                    module,
                    options.memory,
                    startArg,
                );
            },
        },
        /* #endif */
        /* #endif */
    };
    const importsContext = {
        getInstance: () => instance,
        getExports: () => exports,
        _swift: swift,
    };
    instantiator.addImports(importObject, importsContext);
    options.addToCoreImports?.(importObject, importsContext);

    let module;
    let instance;
    let exports;
    if (moduleSource instanceof _WebAssembly.Module) {
        module = moduleSource;
        instance = await _WebAssembly.instantiate(module, importObject);
    } else if (
        typeof Response === "function" &&
        (moduleSource instanceof Response || moduleSource instanceof Promise)
    ) {
        if (typeof _WebAssembly.instantiateStreaming === "function") {
            const result = await _WebAssembly.instantiateStreaming(
                moduleSource,
                importObject,
            );
            module = result.module;
            instance = result.instance;
        } else {
            const moduleBytes = await (await moduleSource).arrayBuffer();
            module = await _WebAssembly.compile(moduleBytes);
            instance = await _WebAssembly.instantiate(module, importObject);
        }
    } else {
        // @ts-expect-error: Type 'Response' is not assignable to type 'BufferSource'
        module = await _WebAssembly.compile(moduleSource);
        instance = await _WebAssembly.instantiate(module, importObject);
    }
    instance =
        options.instrumentInstance?.(instance, { _swift: swift }) ?? instance;

    swift.setInstance(instance);
    instantiator.setInstance(instance);
    exports = instantiator.createExports(instance);

    return {
        instance,
        swift,
        exports,
    };
}