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 adds support for stdio in picolibc and fixes wasm_exec.js so that
it can also support C puts. With this, C stdout works on all supported
platforms.
This improves compatibility between the regular browser target
(-target=wasm) and the WASI target (-target=wasi). Specifically, it
allows running WASI tests like this:
tinygo test -target=wasi encoding/base32
For example, for running tests with -target=wasm or
-target=cortex-m-qemu. It looks at the output to determine whether tests
were successful in the absence of a status code.
See commit:
54e6ba6724
Warning: this will drop support for Go 1.13 for WebAssembly targets!
I have modified the integration tests to specifically blacklist Go 1.13
instead of whitelisting any other version, to avoid accidentally not
testing WebAssembly.
This allows TinyGo-built binaries to run under wasmtime, for example:
tinygo build -o test.wasm -no-debug -target=wasm examples/test
wasmtime run test.wasm 0
The wasm_exec.js file copied from the main Go repository did write those
values to address 4096 in linear memory, which led to memory corruption
in linear memory. Remove these things for now, until they're actually
supported, if support is ever added.
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.
Before this commit, goroutine support was spread through the compiler.
This commit changes this support, so that the compiler itself only
generates simple intrinsics and leaves the real support to a compiler
pass that runs as one of the TinyGo-specific optimization passes.
The biggest change, that was done together with the rewrite, was support
for goroutines in WebAssembly for JavaScript. The challenge in
JavaScript is that in general no blocking operations are allowed, which
means that programs that call time.Sleep() but do not start goroutines
also have to be scheduled by the scheduler.
