This commit adds support for LLVM 16 and switches to it by default. That
means three LLVM versions are supported at the same time: LLVM 14, 15,
and 16.
This commit includes work by QuLogic:
* Part of this work was based on a PR by QuLogic:
https://github.com/tinygo-org/tinygo/pull/3649
But I also had parts of this already implemented in an old branch I
already made for LLVM 16.
* QuLogic also provided a CGo fix here, which is also incorporated in
this commit:
https://github.com/tinygo-org/tinygo/pull/3869
The difference with the original PR by QuLogic is that this commit is
more complete:
* It switches to LLVM 16 by default.
* It updates some things to also make it work with a self-built LLVM.
* It fixes the CGo bug in a slightly different way, and also fixes
another one not included in the original PR.
* It does not keep compiler tests passing on older LLVM versions. I
have found this to be quite burdensome and therefore don't generally
do this - the smoke tests should hopefully catch most regressions.
Browsers previously didn't support the WebAssembly i64 type, so we had
to work around that limitation by converting the LLVM i64 type to
something else. Some people used a pair of i32 values, but we used a
pointer to a stack allocated i64.
Now however, all major browsers and Node.js do support WebAssembly
BigInt integration so that i64 values can be passed back and forth
between WebAssembly and JavaScript easily. Therefore, I think the time
has come to drop support for this workaround.
For more information: https://v8.dev/features/wasm-bigint (note that
TinyGo has used a slightly different way of passing i64 values between
JS and Wasm).
For information on browser support: https://webassembly.org/roadmap/
This basically reverts https://github.com/tinygo-org/tinygo/pull/3357
and replaces it with a different mechanism to get to the same goal.
I do not think filtering tags like this is a good idea: it's the wrong
part of the compiler to be concerned with such tags (that part sets
tags, but doesn't modify existing tags). Instead, I've written the
//go:build lines in such a way that it has the same effect: WASI
defaults to leveldb, everything else defaults to fnv, and it's possible
to override the default using build tags.
This allows you to expand {tmpDir} in the json "emulator" field, and
uses it in wasmtime instead of custom TMPDIR mapping logic.
Before, we had custom logic for wasmtime to create a separate tmpDir
when running go tests. This overwrite the TMPDIR variable when running,
after making a mount point. A simpler way to accomplish the end goal of
writing temp files is to use wasmtime's map-dir instead. When code is
compiled to wasm with the wasi target, tempDir is always /tmp, so we
don't need to add variables (since we know what it is). Further, the
test code is the same between normal go and run through wasmtime. So, we
don't need to make a separate temp dir first, and avoiding that reduces
logic, as well makes it easier to swap out the emulator (for wazero
which has no depedencies). To map the correct directory, this introduces
a {tmpDir} token whose value is the host-specific value taken from
`os.TempDir()`.
The motivation I have for this isn't so much to clean up the wasmtime
code, but allow wazero to execute the same tests. After this change, the
only thing needed to pass tests is to change the emulator, due to
differences in how wazero deals with relative lookups (they aren't
restricted by default, so there's not a huge amount of custom logic
needed).
In other words, installing wazero from main, `make tinygo-test-wasi`
works with no other changes except this PR and patching
`targets/wasi.json`.
```json
"emulator": "wazero run -mount=.:/ -mount={tmpDir}:/tmp {}",
```
On that note, if there's a way to override the emulator via arg or env,
this would be even better, but in any case patching json is fine.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
Scanning of allocas was entirely broken on WebAssembly. The code
intended to do this was never run. There were also no tests.
Looking into this further, I found that it is actually not really
necessary to do that: the C stack can be scanned conservatively and in
fact this was already done for goroutine stacks (because they live on
the heap and are always referenced). It wasn't done for the system stack
however.
With these fixes, I believe code should be both faster *and* more
correct.
I found this in my work to get opaque pointers supported in LLVM 15,
because the code that was never reached now finally got run and was
actually quite buggy.
--allow-undefined can be a problem: it allows compiling code that will
fail when loaded. This change makes sure that if some symbols are
undefined, they are reported as an error by the linker.
Previously, people could get away with importing a function that was not
defined, like this:
func add(int a, int b) int
func test() {
println(add(3, 5))
}
This was always unintended but mostly worked. With this change, it isn't
possible anymore. Now every function needs to be marked with //export
explicitly:
//export add
func add(int a, int b) int
func test() {
println(add(3, 5))
}
As before, functions will be placed in the `env` module with the name
set from the `//export` tag. This can be overridden with
`//go:import-module`:
//go:import-module math
//export add
func add(int a, int b) int
func test() {
println(add(3, 5))
}
For the syscall/js package, I needed to give a list of symbols that are
undefined. This list is based on the JavaScript functions defined in
targets/wasm_exec.js.
This commit will start to use a few more WebAssembly features, such as
bulk memory operations. This results in a significant code size saving.
How much it saves varies a lot but it's typically around 1300 bytes.
This change is possible by bumping our minimum Node.js version to 14.
The previous LTS version (12) has been marked end of life, so we can
start to depend on features in the current oldest LTS version, which is
version 14. Browsers have been supporting these features for a long time
now, it's just Node.js that prevented us doing this before.
This matches the flash-command and is generally a bit easier to work
with.
This commit also prepares for allowing multiple formats to be used in
the emulator command, which is necessary for the esp32.
Exporting symbols seems to embed them in the WASM exports section which
causes wasmtime to fail: https://github.com/bytecodealliance/wasmtime/issues/2587
As a workaround, it is possible to specify the `--allow-unknown-exports`
flag on wasmtime.
But as discussed in the above linked issue, this seems to only be a
workaround. For the Rust compiler the fix was to remove the
`--export-dynamic` linker flag when targeting `wasm32-wasi`:
https://github.com/rust-lang/rust/pull/81255
Which is waht this commit does for Tinygo too.
This change implements a new "scheduler" for WebAssembly using binaryen's asyncify transform.
This is more reliable than the current "coroutines" transform, and works with non-Go code in the call stack.
runtime (js/wasm): handle scheduler nesting
If WASM calls into JS which calls back into WASM, it is possible for the scheduler to nest.
The event from the callback must be handled immediately, so the task cannot simply be deferred to the outer scheduler.
This creates a minimal scheduler loop which is used to handle such nesting.
This brings a bit more consistency to libc configuration. It seems
better to me to set the header flags all in the same place, instead of
some in Go code and some in JSON target files (depending on the target).
This is for consistency with Clang, which always adds a CPU flag even if
it's not specified in CFLAGS.
This commit also adds some tests to make sure the Clang target-cpu
matches the CPU property in the JSON files.
This does have an effect on the generated binaries. The effect is very
small though: on average just 0.2% increase in binary size, apparently
because Cortex-M3 and Cortex-M4 are compiled a bit differently. However,
when rebased on top of https://github.com/tinygo-org/tinygo/pull/2218
(minsize), the difference drops to -0.1% (a slight decrease on average).
This commit changes a target triple like "armv6m-none-eabi" to
"armv6m-unknown-unknow-eabi". The reason is that while the former is
correctly parsed in Clang (due to normalization), it wasn't parsed
correctly in LLVM meaning that the environment wasn't set to EABI.
This change normalizes all target triples and uses the EABI environment
(-eabi in the triple) for Cortex-M targets.
This change also drops the `--target=` flag in the target JSON files,
the flag is now added implicitly in `(*compileopts.Config).CFlags()`.
This removes some duplication in target JSON files.
Unfortunately, this change also increases code size for Cortex-M
targets. It looks like LLVM now emits calls like __aeabi_memmove instead
of memmove, which pull in slightly more code (they basically just call
the regular C functions) and the calls themself don't seem to be as
efficient as they could be. Perhaps this is a LLVM bug that will be
fixed in the future, as this is a very common occurrence.
This brings some consistency to the CFlags and fixes the issue that on
some platforms (Linux, MacOS), no optimization level was set and
therefore C files in packages were not optimized at all.
The wasm build tag together with GOARCH=arm was causing problems in the
internal/cpu package. In general, I think having two architecture build
tag will only cause problems (in this case, wasm and arm) so I've
removed the wasm build tag and replaced it with tinygo.wasm.
This is similar to the tinygo.riscv build tag, which is used for older
Go versions that don't yet have RISC-V support in the standard library
(and therefore pretend to be GOARCH=arm instead).
At the moment, all targets use the Clang compiler to compile C and
assembly files. There is no good reason to make this configurable
anymore and in fact it will make future changes more complicated (and
thus more likely to have bugs). Therefore, I've removed support for
setting the compiler.
Note that the same is not true for the linker. While it makes sense to
standardize on the Clang compiler (because if Clang doesn't support a
target, TinyGo is unlikely to support it either), linkers will remain
configurable for the foreseeable future. One example is Xtensa, which is
supported by the Xtensa LLVM fork but doesn't have support in ld.lld
yet.
I've also fixed a bug in compileAndCacheCFile: it wasn't using the right
CFlags for caching purposes. This could lead to using stale caches. This
commit fixes that too.
This way is more consistent with how picolibc is specified and allows
generating a helpful error message. This error message should never be
generated for TinyGo binary releases, only when doing local development.
* initial commit for WASI support
* merge "time" package with wasi build tag
* override syscall package with wasi build tag
* create runtime_wasm_{js,wasi}.go files
* create syscall_wasi.go file
* create time/zoneinfo_wasi.go file as the replacement of zoneinfo_js.go
* add targets/wasi.json target
* set visbility hidden for runtime extern variables
Accodring to the WASI docs (https://github.com/WebAssembly/WASI/blob/master/design/application-abi.md#current-unstable-abi),
none of exports of WASI executable(Command) should no be accessed.
v0.19.0 of bytecodealliance/wasmetime, which is often refered to as the reference implementation of WASI,
does not accept any exports except functions and the only limited variables like "table", "memory".
* merge syscall_{baremetal,wasi}.go
* fix js target build
* mv wasi functions to syscall/wasi && implement sleepTicks
* WASI: set visibility hidden for globals variables
* mv back syscall/wasi/* to runtime package
* WASI: add test
* unexport wasi types
* WASI test: fix wasmtime path
* stop changing visibility of runtime.alloc
* use GOOS=linux, GOARCH=arm for wasi target
Signed-off-by: mathetake <takeshi@tetrate.io>
* WASI: fix build tags for os/runtime packages
Signed-off-by: mathetake <takeshi@tetrate.io>
* run WASI test only on Linux
Signed-off-by: mathetake <takeshi@tetrate.io>
* set InternalLinkage instead of changing visibility
Signed-off-by: mathetake <takeshi@tetrate.io>
This allows CGo code to call some libc functions. Additionally, by
putting memset/memmove/memcpy in an archive they're not included anymore
when not necessary, reducing code size for small programs.
This makes sure that a stack overflow will cause a "memory access out of
bounds" error instead of a corruption of a global variable.
Here is more background on a very similar stack overflow protection:
https://blog.japaric.io/stack-overflow-protection/
This commit does a few things:
* remove the -8 suffix on macOS, where it is not necessary
* add smoke tests for compiling wasm files on Linux and macOS
Unfortunately, the olin/cwa emulator does not handle floats correctly.
Node.js does, and because it is also supported by the Go WebAssembly
implementation it has better support in general.
When building statically against LLVM, LLD is also included now. When
included, the built in wasm-ld will automatically be used instead of the
external command.
There is also support for linking ELF files but because lld does not
fully support armv6m this is not yet enabled (it produces a warning).
Undefined symbols will be shown by the embedder, for example when
running generated wasm files in a browser.
In the future, this should probably become a fixed list again. But for
experimenting it's easier now to just ignore undefined symbols and
expect the JS to provide them.
Ayke van Laethem
deadprogram
Randy Reddig
Charlie Haley
Adrian Cole
Damian Gryski
ZauberNerd
Nia Waldvogel
Takeshi Yoneda
Elliott Sales de Andrade
Hiroki Noda