Add wasm backend to custom build tool

tfjs-backend-wasm/package.json

@@ -20,6 +20,7 @@
     "publish-local": "rimraf dist/ && yarn build && rollup -c && yalc push",
     "build-ci": "./scripts/build-ci.sh",
     "build-npm": "./scripts/build-npm.sh",
+    "build-fast": "tsc && yarn rollup -c",
     "build-benchmark": "./scripts/build-benchmark.sh",
     "buildifier-ci": "./scripts/buildifier-ci.sh",
     "clean": "rimraf dist/ && bazel clean --expunge",

tfjs-backend-wasm/src/base.ts

@@ -0,0 +1,19 @@
+/**
+ * @license
+ * Copyright 2020 Google LLC. All Rights Reserved.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * =============================================================================
+ */
+
+export {BackendWasm, setWasmPath, setWasmPaths} from './backend_wasm';
+export {version as version_wasm} from './version';

tfjs-backend-wasm/src/index.ts

@@ -16,6 +16,4 @@
  */
 
 import './register_all_kernels';
-
-export {BackendWasm, setWasmPath, setWasmPaths} from './backend_wasm';
-export {version as version_wasm} from './version';
+export * from './base';

tfjs/tools/custom_bundle/cli.ts

@@ -81,7 +81,8 @@ function validateArgs(): CustomTFJSBundleConfig {
 
   for (const requestedBackend of finalConfig.backends) {
     if (requestedBackend !== SupportedBackends.cpu &&
-        requestedBackend !== SupportedBackends.webgl) {
+        requestedBackend !== SupportedBackends.webgl &&
+        requestedBackend !== SupportedBackends.wasm) {
       bail(`Error: Unsupported backend specified '${requestedBackend}'`);
     }
   }

tfjs/tools/custom_bundle/esm_module_provider.ts

@@ -71,6 +71,8 @@ function getBackendPath(backend: SupportedBackend) {
       return '@tensorflow/tfjs-backend-cpu';
     case 'webgl':
       return '@tensorflow/tfjs-backend-webgl';
+    case 'wasm':
+      return '@tensorflow/tfjs-backend-wasm';
     default:
       throw new Error(`Unsupported backend ${backend}`);
   }

tfjs/tools/custom_bundle/types.ts

@@ -17,7 +17,8 @@
 
 export enum SupportedBackends {
   cpu = 'cpu',
-  webgl = 'webgl'
+  webgl = 'webgl',
+  wasm = 'wasm'
 }
 export type SupportedBackend = keyof typeof SupportedBackends;