### Description
This PR revises the backend registration.
The following describes the expected behavior after this change:
(**bolded are changed behavior**)
- (ort.min.js - built without webgpu support)
- loading: do not register 'webgpu' backend
- creating session without EP list: use default EP list ['webnn', 'cpu',
'wasm']
- creating session with ['webgpu'] as EP list: should fail with backend
not available
- (ort.webgpu.min.js - built with webgpu support)
- loading: **always register 'webgpu' backend**
( previous behavior: only register 'webgpu' backend when `navigator.gpu`
is available)
- creating session without EP list: use default EP list ['webgpu',
'webnn', 'cpu', 'wasm']
- when WebGPU is available (win): use WebGPU backend
- when WebGPU is unavailable (android): **should fail backend init,**
and try to use next backend in the list, 'webnn'
(previous behavior: does not fail backend init, but fail in JSEP init,
which was too late to switch to next backend)
- creating session with ['webgpu'] as EP list
- when WebGPU is available (win): use WebGPU backend
- when WebGPU is unavailable (android): **should fail backend init, and
because no more EP listed, fail.
related PRs: #18190#18144
### Description
- set tsconfig "noUnusedParameters" to `true` and fix a few bugs
discovered by typescript.
how unused parameter is fixed:
- for most code (webgl), add underscore as prefix, which is the standard
ignore pattern for typescript check.
- remove unused parameter from function and modify corresponding
function calls (jsep)
- fix a bug in ArgMinMax: this 2 operators do not have more than one
input(s) so the `createArgMinMaxAttributesFromInputs()` is removed.
- add proxy main.ts into typescript check and fix a bug in parameter
passing
- fixed `run()` function call and add typecheck fix (hack)
### Description
* Adds TrainingSession.create() functionality following the web bindings
for training design doc
* Added 2 new training APIs to wasm/api.h:
* OrtTrainingGetInputOutputName
* OrtTrainingGetInputOutputCount
* Moved isOrtEnvInitialized boolean to the wasm-core-impl and added a
method that references it
### Motivation and Context
* Adding web bindings for training
#### Related work
* #16521 allowed for training artifacts to be built
* #17333 added interfaces for training
* #17474 allows for training package to be built + adds training backend
to web package **[MUST BE MERGED IN BEFORE THIS ONE]**
---------
Co-authored-by: Yulong Wang <7679871+fs-eire@users.noreply.github.com>
Co-authored-by: Ashwini Khade <askhade@microsoft.com>
### Description
Use esbuild to accelerate bundle build.
This change uses esbuild to replace webpack for onnxruntime-web. Bundle
build time reduced from ~20sec to ~0.6sec on my windows dev box.
A few changes applied:
- import nodejs modules using "node:" prefix
- remove enum declaration inside namespace (EncoderUsage)
- use "fs/promise" to replace the old promisify from "util"
- separate ort-web and test-runner. Previously they are bundled
together, now they are built into 2 files.
- optimize karma runner launch time
- remove unnecessary sourcemap preprocessor. sourcemaps are handled
inside esbuild
- remove unnecessary proxies (because ort-web and test-runner are
separated now, the path are correctly inferred)
- remove file watcher for test data
- optimize special handling as esbuild plugins:
- polyfill dummy imports for node.js modules when targetting browser.
- load as content string for ort-wasm-*.worker.js
- load as content string for ./proxy-worker/main.ts
- a source patch to ort-wasm*-threaded*.js (see details in comments in
code)
- updated debug configurations for sourcemap mapping to ensure
out-of-box good dev experience
### Description
This change introduced the following new components into ONNX Runtime
Web:
- JavaScript Execution Provider (JSEP)
- Asynchronized inferencing execution powered by Emscripten's Asyncify
- WebGPU backend implemented in TypeScript
- initial implementation of kernels:
- elementwise operators (22)
- binary operators (5)
- tensor: Shape, Reshape, Transpose, Gemm
- nn: Conv, {Global}Maxpool, {Global}AveragePool
Code need to be polished. still working on it.
## Q&A
What is JSEP?
> JSEP, aka JavaScript Execution Provider, is a new ONNXRuntime
execution provider that specifically works on Web environment
(browsers). JSEP allows JavaScript code to kick in from various places
when ONNX Runtime inferences a model.
Why JSEP?
> JSEP is a hybrid mode EP that contains both C/C++ and
TypeScript/JavaScript implementation. There are 2 strong reasons why we
introduces JSEP:
> 1. the C/C++ part helps JSEP to leverage ONNX Runtime's capabilities
as much as possible including graph transformer, optimizers and also the
capabilities to fallback to CPU EP. TypeScript/JavaScript helps JSEP to
develop and debug much easier in the browser for the kernel
implementation.
> 2. the requirement of asynchronized execution from JavaScript API (eg.
`buffer.mapAsync()`) makes it impossible to run `OrtRun()` in a
synchronized context (see "async problem" section below). This is done
by using Emscripten's Asyncify.
What is WebGPU?
> WebGPU is the new GPU API that available in browser. It's one of the
only 2 APIs that currently available to access the GPU from browser (the
other is WebGL).
> WebGPU is designed with more advanced and stronger features comparing
to WebGL and is potentially solution that offer the best GPU performance
for model inferencing that currently available.
What is the async problem and why we have the problem?
> The "async problem" is a problem that you cannot call an async
function in a synchronous context. Think about the following C++ code:
> ```c
> // C-style declarations (API)
> typedef void (*ON_COMPLETE)(PVOID state, DATA *data);
> void read_data_from_file(FILEHANDLE file, ON_COMPLETE on_complete);
>
> // implementation
> DATA * my_impl_read_data_from_file_sync(FILEHANDLE file) {
> // how to implement?
> }
> ```
> The answer is, it's impossible to implement this function. Usually we
try to find a sync version API, or launch a thread to call the async
function and sync-wait on the main thread. Unfortunately, in browser
environment, neither is possible.
>
> WebGPU does not offer any synchronized API for data downloading (GPU
to CPU). This is the only operation that MUST be async. As `OrtRun()`
will eventually call into DataTransfer for copy data from GPU to CPU,
and `OrtRun()` is a synchronized function, this cannot be done in normal
way.
What is Emscripten? How is the Asyncify feature resolved the problem?
> Emscripten is the C/C++ compiler for WebAssembly. It's what we use to
compile ORT and generates the WebAssembly artifacts which runs on
browsers.
>
> Asyncify is a [compiler
feature](https://emscripten.org/docs/porting/asyncify.html) that allows
calling async functions from a synchronized context. In short, it
generates code to unwind and rewind call stack to emulate async
execution. With this feature, we are able to call the async function
inside `OrtRun()` call.
## Design Overview
**Inter-op**
JSEP is doing pretty much same thing to just another EP. It exposes an
interface for inter-op with JavaScript, which is defined in
onnxruntime/wasm/js_internal_api.js:
```js
// init JSEP
Module["jsepInit"] = function (backend, alloc, free, copy, copyAsync, createKernel, releaseKernel, run) {
Module.jsepBackend = backend;
Module.jsepAlloc = alloc;
Module.jsepFree = free;
Module.jsepCopy = copy;
Module.jsepCopyAsync = copyAsync;
Module.jsepCreateKernel = createKernel;
Module.jsepReleaseKernel = releaseKernel;
Module.jsepRun = run;
};
```
This simple JavaScript snippet defines all language barrier level
functions that requires by JSEP to achieve implementing kernels and data
transfers using JavaScript inside ONNX Runtime:
- `jsepBackend`: assign the singleton object to webassembly module
- `jsepAlloc` and `jsepFree`: implementation of data transfer's Alloc()
and Free()
- `jsepCopy`: synchronized copy ( GPU to GPU, CPU to GPU)
- `jsepCopyAsync`: asynchronized copy ( GPU to CPU)
- `jsepCreateKernel` and `jsepReleaseKernel`: a corresponding object
that maintained in JS to match lifecycle of Kernel in ORT
- `jsepRun`: OpKernel::Compute() should call into this
The abstraction above allows to tie as little as possible connections
and dependencies between C/C++ and TypeScript/JavaScript.
**Resource Management**
Lifecycle of tensor data and kernels are managed by ORT(C/C++) but the
implementation are left to JavaScript. JavaScript code are responsible
to implement the callbacks correctly.
For WebGPU, the GPU data is managed by JavaScript using a singleton map
(tensot_data_id => GPUBuffer). GPU pipeline is managed as singleton.
Shaders are managed using a singletonmap (shader_key => gpu_program),
while shader_key is generated by cache_key (OP specific, including
attributes) and input shapes.
**about data transfer**
`js::DataTransfer::CopyTensor` implemented to call either synchronized
or asynchronized copy callback, depending on the destination is GPU or
not. Emscripten's macro `EM_ASYNC_JS` is used to wrap the async function
to be called in the synchronized context.
**run kernel in JS**
Kernel class constructor calls once `jsepCreateKernel()` with an
optional per-kernel specific serialization to pass attributes into
JavaScript.
`Compute()` are implemented in a way that a metadata serialization is
performed in a base class and JavaScript code can access the data using
the Emscripten specific builtin macro `EM_ASM_*`.
**disabled features**
memory pattern is force disabled, because the WebGPU data is not
presented by a general memory model (a buffer can be represented by
offset + size).
concurrent run support is disabled. WebGPU is stateful and it also has
async function call. To support concurrent run will significantly
increase the complexity and we don't get any real benefit from it.
**prefer channels last**
JSEP prefers channels last and returns `DataLayout::NHWC` in method
`GetPreferredLayout()`. This will let the graph transformers to
preprocess the graph into a channels last form so that a more optimized
WebGPU shader can be used.
**Testing code**
It's impossible to test JSEP directly because JSEP itself does not
contain any kernel implementation. However, it has the kernel
registration which need to work together with the corresponding
JavaScript code. There are unit tests that run onnx models from
JavaScript API.
---------
Co-authored-by: Scott McKay <skottmckay@gmail.com>
