Formerly, we introduced `wazero.Namespace` to help avoid module name or import conflicts while still sharing the runtime's compilation cache. Now that we've introduced `CompilationCache` `wazero.Namespace` is no longer necessary. By removing it, we reduce the conceptual load on end users as well internal complexity. Since most users don't use namespace, the change isn't very impactful.
Users who are only trying to avoid module name conflict can generate a name like below instead of using multiple runtimes:
```go
moduleName := fmt.Sprintf("%d", atomic.AddUint64(&m.instanceCounter, 1))
module, err := runtime.InstantiateModule(ctx, compiled, config.WithName(moduleName))
```
For `HostModuleBuilder` users, we no longer take `Namespace` as the last parameter of `Instantiate` method:
```diff
// log to the console.
_, err := r.NewHostModuleBuilder("env").
NewFunctionBuilder().WithFunc(logString).Export("log").
- Instantiate(ctx, r)
+ Instantiate(ctx)
if err != nil {
log.Panicln(err)
}
```
The following is an example diff a use of namespace can use to keep compilation cache while also ensuring their modules don't conflict:
```diff
func useMultipleRuntimes(ctx context.Context, cache) {
- r := wazero.NewRuntime(ctx)
+ cache := wazero.NewCompilationCache()
for i := 0; i < N; i++ {
- // Create a new namespace to instantiate modules into.
- ns := r.NewNamespace(ctx) // Note: this is closed when the Runtime is
+ r := wazero.NewRuntimeWithConfig(ctx, wazero.NewRuntimeConfig().WithCompilationCache(cache))
// Instantiate a new "env" module which exports a stateful function.
_, err := r.NewHostModuleBuilder("env").
```
Signed-off-by: Takeshi Yoneda <takeshi@tetrate.io>
This introduces the new API wazero.Cache interface which can be passed to wazero.RuntimeConfig.
Users can configure this to share the underlying compilation cache across multiple wazero.Runtime.
And along the way, this deletes the experimental file cache API as it's replaced by this new API.
Signed-off-by: Takeshi Yoneda <takeshi@tetrate.io>
Co-authored-by: Crypt Keeper <64215+codefromthecrypt@users.noreply.github.com>
This changes the listener signature to accept context and calling
module, so that all possible parameters and results can be logged. This
also changes the logging listener to make parameters visible when
logging results.
This infrastructure supports some helpful use cases, such as logging
WASI result parameters, such as the prestat path, which is only knowable
after the function has been called. The context parameter supposed
reading results of gojs functions, which are stored host-side in a go
context object.
Future pull requests will complete this as well backfill unit tests.
This is raised independently mainly to keep the PR size down of the
upcoming filesystem logger.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
We originally had a `context.Context` for anything that might be
traced, but it turned out to be only useful for lifecycle and host functions.
For instruction-scoped aspects like memory updates, a context parameter is too
fine-grained and also invisible in practice. For example, most users will use
the compiler engine, and its memory, global or table access will never use go's
context.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This changes the log listener to assume a value is signed instead of
unsigned, as it leads to logs looking more correct than the other way
around. Notably, values that are often negative, such as seek offset,
look better without a lot of downside.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This adds ResultNames to HostFunctionBuilder and FunctionDefinition
which helps for multi-results or special-cased ones.
End users can access result names in `FunctionDefinition.ResultNames` or
set for their own host functions via
`HostFunctionBuilder.WithResultNames`. This change adds them for all
built-in functions where result names help.
Most notably, GOOS=js uses `ProxyFunc` to allow logging when a function
returns multiple results. Before, the results were returned without
names: e.g. `11231,1` and now they are named like `n=11231,ok=1`.
We soon plan to allow more visibility in WASI, for example, logging
results that will write to memory offsets. This infrastructure makes it
possible to do that.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This adds host functions that work on dynamic function tables. These are
only used by emscripten, but require some infrastructure to support it.
I added the least possible to due the task. This also only handles i32
and void returns with up to four parameters as that covers the needs of
PDFium. Future integrations may need more parameters or a mix of floats.
Such use cases should be addressed as they come as otherwise it is a lot
of work for the cartesian product of all combinations.
See 1b0d724fd5/test/passes/post-emscripten.wast
See https://github.com/jerbob92/go-pdfium-wasm
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This switches to gofumpt and applies changes, as I've noticed working
in dapr (who uses this) that it finds some things that are annoying,
such as inconsistent block formatting in test tables.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This restores the ability to leave out the initial context parameter
when defining functions with reflection. This is important because some
projects are porting from a different library to wazero, and all the
alternatives are not contextualized.
For example, this project is porting envoy host functions, and the
original definitions (in mosn) don't have a context parameter. By being
lenient, they can migrate easier.
See 6b813482b6/pkg/proxywasm/wazero/imports_v1.go
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This PR follows @hafeidejiangyou advice to not only enable end users to
avoid reflection when calling host functions, but also use that approach
ourselves internally. The performance results are staggering and will be
noticable in high performance applications.
Before
```
BenchmarkHostCall/Call
BenchmarkHostCall/Call-16 1000000 1050 ns/op
Benchmark_EnvironGet/environGet
Benchmark_EnvironGet/environGet-16 525492 2224 ns/op
```
Now
```
BenchmarkHostCall/Call
BenchmarkHostCall/Call-16 14807203 83.22 ns/op
Benchmark_EnvironGet/environGet
Benchmark_EnvironGet/environGet-16 951690 1054 ns/op
```
To accomplish this, this PR consolidates code around host function
definition and enables a fast path for functions where the user takes
responsibility for defining its WebAssembly mappings. Existing users
will need to change their code a bit, as signatures have changed.
For example, we are now more strict that all host functions require a
context parameter zero. Also, we've replaced
`HostModuleBuilder.ExportFunction` and `ExportFunctions` with a new type
`HostFunctionBuilder` that consolidates the responsibility and the
documentation.
```diff
ctx := context.Background()
-hello := func() {
+hello := func(context.Context) {
fmt.Fprintln(stdout, "hello!")
}
-_, err := r.NewHostModuleBuilder("env").ExportFunction("hello", hello).Instantiate(ctx, r)
+_, err := r.NewHostModuleBuilder("env").
+ NewFunctionBuilder().WithFunc(hello).Export("hello").
+ Instantiate(ctx, r)
```
Power users can now use `HostFunctionBuilder` to define functions that
won't use reflection. There are two choices of interfaces to use
depending on if that function needs access to the calling module or not:
`api.GoFunction` and `api.GoModuleFunction`. Here's an example defining
one.
```go
builder.WithGoFunction(api.GoFunc(func(ctx context.Context, params []uint64) []uint64 {
x, y := uint32(params[0]), uint32(params[1])
sum := x + y
return []uint64{sum}
}, []api.ValueType{api.ValueTypeI32, api.ValueTypeI32}, []api.ValueType{api.ValueTypeI32})
```
As you'll notice and as documented, this approach is more verbose and
not for everyone. If you aren't making a low-level library, you are
likely able to afford the 1us penalty for the convenience of reflection.
However, we are happy to enable this option for foundational libraries
and those with high performance requirements (like ourselves)!
Fixes#825
Signed-off-by: Adrian Cole <adrian@tetrate.io>
It is more often the case that projects are enabling a freestanding
target, and that may or may not have an exporting memory depending on
how that's interpreted. This adds the ability to inspect memories
similar to how you can already inspect compiled code prior to
instantiation. For example, you can enforce an ABI constraint that
"memory" must be exported even if WASI is not in use.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
We at one point considered making `ModuleBuilder` create complete
WebAssembly binaries. However, we recently spun out
[wabin](https://github.com/tetratelabs/wabin), which allows this.
Meanwhile, the features in `ModuleBuilder` were confusing and misused.
For example, the only two cases memory was exported on GitHub were done
by accident. This is because host functions act on the guest's memory,
not their own.
Hence, this removes memory and globals from host side definitions, and
renames the type to HostModuleBuilder to clarify this is not ever going
to be used to construct normal Wasm binaries.
Most importantly, this simplifies the API and reduces a lot of code. It
is important to make changes like this, particularly deleting any
experimental things that didn't end up useful.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
Co-authored-by: Anuraag Agrawal <anuraaga@gmail.com>
While compilers should be conservative when targeting WebAssembly Core
features, runtimes should be lenient as otherwise people need to
constantly turn on all features. Currently, most examples have to turn
on 2.0 features because compilers such as AssemblyScript and TinyGo use
them by default. This matches the policy with the reality, and should
make first time use easier.
This top-levels an internal type as `api.CoreFeatures` and defaults to
2.0 as opposed to 1.0, our previous default. This is less cluttered than
the excess of `WithXXX` methods we had prior to implementing all
planned WebAssembly Core Specification 1.0 features.
Finally, this backfills rationale as flat config types were a distinct
decision even if feature set selection muddied the topic.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This simplifies the calling convention and consolidates the call frame stack
and value stack into a single stack.
As a result, the cost of function calls decreases because we now don't need
to check the boundary twice (value and call frame stacks) at each function call.
The following is the result of the benchmark for recursive Fibonacci
function in integration_test/bench/testdata/case.go, and it shows that
this actually improves the performance of function calls.
[amd64]
name old time/op new time/op delta
Invocation/compiler/fib_for_5-32 109ns ± 3% 81ns ± 1% -25.86% (p=0.008 n=5+5)
Invocation/compiler/fib_for_10-32 556ns ± 3% 473ns ± 3% -14.99% (p=0.008 n=5+5)
Invocation/compiler/fib_for_20-32 61.4µs ± 2% 55.9µs ± 5% -8.98% (p=0.008 n=5+5)
Invocation/compiler/fib_for_30-32 7.41ms ± 3% 6.83ms ± 3% -7.90% (p=0.008 n=5+5)
[arm64]
name old time/op new time/op delta
Invocation/compiler/fib_for_5-10 67.7ns ± 1% 60.2ns ± 1% -11.12% (p=0.000 n=9+9)
Invocation/compiler/fib_for_10-10 487ns ± 1% 460ns ± 0% -5.56% (p=0.000 n=10+9)
Invocation/compiler/fib_for_20-10 58.0µs ± 1% 54.3µs ± 1% -6.38% (p=0.000 n=10+10)
Invocation/compiler/fib_for_30-10 7.12ms ± 1% 6.67ms ± 1% -6.31% (p=0.000 n=10+9)
Signed-off-by: Takeshi Yoneda <takeshi@tetrate.io>