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>
This introduces wasm.CallEngine internal type, and assign it to the api.Function
implementations. api.Function.Call now uses that CallEngine assigned to it
to make function calls.
Internally, when creating CallEngine implementation, the compiler engine allocates
call frames and values stack. Previously, we allocate these stacks for each function calls,
which was a severe overhead as we can recognize in the benchmarks. As a result,
this reduces the memory usage (== reduces the GC jobs) as long as we reuse
the same api.Function multiple times.
As a side effect, now api.Function.Call is not goroutine-safe. So this adds the comment
about it on that method.
Signed-off-by: Takeshi Yoneda <takeshi@tetrate.io>
Before, we allowed stubbed host functions to be defined in wasm instead
of Go. This improves performance and reduces a chance of side-effects vs
Go. In fact, any pure function was supported in wasm, provided it only
called pure functions.
This changes internals so that a wasm-defined host function can use
memory. Notably, host functions use the caller's memory, so this is
simpler to initially support in the interpreter.
This is needed to simplify and reduce performance hit of GOARCH=wasm,
GOOS=js code, which perform a lot of memory reads and do not have
idiomatic signatures.
Note: wasm-defined host functions remain internal until we gain
experience, at least conclusion of the wasm_exec host module.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
* Makes CacheNumInUint64 lazy and stops crashing in assemblyscript
This makes CacheNumInUint64 lazy so that all tests for function types
don't need to handle it. This also changes the assemblyscript special
functions so they don't crash when attempting to log. Finally, this
refactors `wasm.Func` so that it can enclose the parameter names as it
is more sensible than defining them elsewhere.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This refactors host functions with no-op or constant returns to be
implemented with wasm instead of the host function bridge. This allows
better performance.
This also breaks up and makes WASI tests consistent, in a way that shows
parameter name drifts easier.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This commit implements the v128.const, i32x4.add and i64x2.add in
interpreter mode and this adds support for the vector value types in the
locals and globals.
Notably, the vector type values can be passed and returned by exported functions
as well as host functions via two-uint64 encodings as described in #484 (comment).
Note: implementation of these instructions on JIT will be done in subsequent PR.
part of #484
Signed-off-by: Takeshi Yoneda <takeshi@tetrate.io>
This commit completes the reference-types proposal implementation.
Notably, this adds support for
* `ref.is_null`, `ref.func`, `ref.is_null` instructions
* `table.get`, `table.set`, `table.grow`, `table.size` and `table.fill` instructions
* `Externref` and `Funcref` types (including invocation via uint64 encoding).
part of #484
Signed-off-by: Takeshi Yoneda <takeshi@tetrate.io>
This is an API breaking change that does a few things:
* Stop encouraging practice that can break context propagation:
* Stops caching `context.Context` in `wazero.RuntimeConfig`
* Stops caching `context.Context` in `api.Module`
* Fixes context propagation in function calls:
* Changes `api.Function`'s arg0 from `api.Module` to `context.Context`
* Adds `context.Context` parameter in instantiation (propagates to
.start)
* Allows context propagation for heavy operations like compile:
* Adds `context.Context` as the initial parameter of `CompileModule`
The design we had earlier was a good start, but this is the only way to
ensure coherence when users start correlating or tracing. While adding a
`context.Context` parameter may seem difficult, wazero is a low-level
library and WebAssembly is notoriously difficult to troubleshoot. In
other words, it will be easier to explain to users to pass (even nil) as
the context parameter vs try to figure out things without coherent
context.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This centralizes logic that gets params and results in and out of
Go-defined functions. This allows us to refactor and optimize easier as
well ensure value coersion is the same regardless of the engine type.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
Co-authored-by: Takeshi Yoneda <takeshi@tetrate.io>
During #425, @neilalexander gave constructive feedback that the API is
both moving fast, and not good enough yet. This attempts to reduce the
incidental complexity at the cost of a little conflation.
### odd presence of `wasm` and `wasi` packages -> `api` package
We had public API packages in wasm and wasi, which helped us avoid
leaking too many internals as public. That these had names that look
like there should be implementations in them cause unnecessary
confusion. This squashes both into one package "api" which has no
package collission with anything.
We've long struggled with the poorly specified and non-uniformly
implemented WASI specification. Trying to bring visibility to its
constraints knowing they are routinely invalid taints our API for no
good reason. This removes all `WASI` commands for a default to invoke
the function `_start` if it exists. In doing so, there's only one path
to start a module.
Moreover, this puts all wasi code in a top-level package "wasi" as it
isn't re-imported by any internal types.
### Reuse of Module for pre and post instantiation to `Binary` -> `Module`
Module is defined by WebAssembly in many phases, from decoded to
instantiated. However, using the same noun in multiple packages is very
confusing. We at one point tried a name "DecodedModule" or
"InstantiatedModule", but this is a fools errand. By deviating slightly
from the spec we can make it unambiguous what a module is.
This make a result of compilation a `Binary`, retaining `Module` for an
instantiated one. In doing so, there's no longer any name conflicts
whatsoever.
### Confusion about config -> `ModuleConfig`
Also caused by splitting wasm into wasm+wasi is configuration. This
conflates both into the same type `ModuleConfig` as it is simpler than
trying to explain a "will never be finished" api of wasi snapshot-01 in
routine use of WebAssembly. In other words, this further moves WASI out
of the foreground as it has been nothing but burden.
```diff
--- a/README.md
+++ b/README.md
@@ -49,8 +49,8 @@ For example, here's how you can allow WebAssembly modules to read
-wm, err := r.InstantiateModule(wazero.WASISnapshotPreview1())
-defer wm.Close()
+wm, err := wasi.InstantiateSnapshotPreview1(r)
+defer wm.Close()
-sysConfig := wazero.NewSysConfig().WithFS(os.DirFS("/work/home"))
-module, err := wazero.StartWASICommandWithConfig(r, compiled, sysConfig)
+config := wazero.ModuleConfig().WithFS(os.DirFS("/work/home"))
+module, err := r.InstantiateModule(binary, config)
defer module.Close()
...
```
This converges host-defined modules with Wasm defined modules by
introducing a custom section for host-defined functions. The net result
are far less types and consistent initialization.
* HostModule is removed for Module
* HostFunction is removed for Function
* ModuleContext is removed for Module
Note: One impact of this is that the low-level API no longer accepts a
go context (context.Context), rather a `wasm.Module` which the function
is called in context of. This meant exposing `wasm.Module.WithContext`
to override the default.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This flattens `FunctionInstance.FunctionType` into `Type` and `TypeID`
fields, where the former is known prior to instantiation. This helps
pave a way for integration between Wasm declared and host defined
modules.
This also clarifies that `FunctionInstance.String` was used as a lookup
key, by renaming and caching its impl. While at it, I renamed "null" to
"v" in its output as I had been using v for void noticing others were
doing that also. Moreover, null is easy to misunderstand as a bug.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
MVP was a term used by WebAssembly insiders when ramping up to the 1.0
spec. While these folks still use that term it is confusing and
unnecessary way to qualify a W3C version. Here are some of the problems:
* MVP does not match a W3C published URL
* MVP does not match a git tag on the spec repo
* MVP was a work in progress, so there are text that say "not in MVP"
which ended up in 1.0 (as MVP became more than it was).
* MVP is jargon to people who don't know that stands for Minimum Viable Product.
This stops this practice and instead uses the W3C 1.0 Draft version
instead: 20191205
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This adds this interface `wasm.Store` which gives access to functions in
a store without leaking an API to change the store. This is primarily to
support configuration use cases where post-initialization, there's no
need or desire to mutate the store. This also backfills codecs needed to
handle float results.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
Signed-off-by: Takeshi Yoneda <takeshi@tetrate.io>
