This makes the meaning more clear. And while the behavior is currently
the same, when we start to use threads we should actually exit the
goroutine when calling runtime.Goexit() instead of just leaving it
deadlocked.
Without this change, a pending interrupt would spuriously trigger
immediately after enabling. This happens if an interrupt is triggered
during flashing (e.g. by DMA), which survives the subsequent reset.
This behaviour matches e.g. `machine.irqSet` in machine_rp2_rp2350.go.
See 7f970a45, whose symptoms were likely caused by spurious interrupts.
For the threads scheduler, it makes sense to have NumCPU available.
For all other schedulers, the number of available CPUs is practically
limited to one by the scheduler (even though the system might have more
CPUs).
A race condition was possible because the 'acquire' goroutine might not
have started in 4 milliseconds which changed the ordering of the test.
This patch fixes it by making sure the goroutine has started (and locked
the mutex) before continuing with the test.
This variable is only necessary on the cooperative and none scheduler.
It is not used on the threads scheduler.
The reason for moving is that the upcoming multicore baremetal scheduler
also needs mainExited but of a different type: an atomic variable
instead of a plain boolean.
This is more descriptive: the call is to exit a task, not to pause it.
This also makes it more obvious that there's an optimization
opportunity: to free the stack explicitly after the goroutine returns
(or to keep it as a cache for the next stack allocation).
This is not a scheduler in the runtime, instead every goroutine is
mapped to a single OS thread - meaning 1:1 scheduling.
While this may not perform well (or at all) for large numbers of
threads, it greatly simplifies many things in the runtime. For example,
blocking syscalls can be called directly instead of having to use epoll
or similar. Also, we don't need to do anything special to call C code -
the default stack is all we need.
Somewhat surprisingly, this results in smaller code than the old code
with the cooperative (tasks) scheduler. Probably because the new RWMutex
is also simpler.
Using a global lock may be slow, but it is certainly simple and safe.
If this global lock becomes a bottleneck, we can of course look into
making the GC truly support multithreading.
This may be a bit of a weird place to put the library path, but
otherwise it's difficult to get the pathname for the Config.CFlags
function. So I've put it here.
This should help to avoid stale library caches. The idea is to increment
it every time something changes to a library that means it needs to be
recompiled. It's a manual process.
Instead of just incrementing the timestamp, this causes the system to
actually sleep when calling time.Sleep. The direct effect is that this
works as expected:
$ tinygo run -target=riscv-qemu examples/serial
hello world!
hello world!
hello world!
[..etc]
This commit also adds a bare bones handler for exceptions (such as
invalid memory writes), since we're adding an interrupt handler anyway.
While this patch doesn't add that much functionality, having interrupt
support is going to be needed for multicore support on riscv-qemu. My
plan is to first add this support to riscv-qemu (based on the earlier
work I did for the RP2040 and demoed at FOSDEM 2025) and once the basics
are in place and fully tested we can extend this support to the RP2040.
Writing for QEMU first makes it much easier to debug any issues that
will come up.
Instead of relying on a build when TinyGo is being built, do it like all
other libraries when it is needed.
This brings a few benefits:
* No more running `make wasi-libc` on the command line as a special
case for WebAssembly. The generic `git submodule update --init` step
is now enough for wasi-libc.
* It becomes much easier to customize the build per system. For
example: include/exclude malloc as needed, disable/enable bulk
memory operations per target, etc.
Header files are built immediately, not in a separate job, so no
dependency is needed here. All we need is a flag whether to add flags
for that given libc.
This *should* not be needed. Using the right `go` binary should do the
job. It might break if users have explicitly set GOROOT (in which case
they probably need to fix that).
This avoids a subprocess call inside `make`.
Instead of calling it 5 times, call it only once on Unix-like systems
(Linux, MacOS) and avoid it entirely on Windows.
The main benefit of this is that it avoids a ton of overhead doing
subprocess calls, which are very slow on Windows (~0.2s on my system).
Most make commands don't need to check for the NodeJS version, so only
do it when needed.
This avoids the following error on Windows for example when NodeJS is
not installed:
/usr/bin/sh: line 1: node: command not found
which: no node in (/c/Users/Ayke/bin:/clangarm64/bin:/usr/local/bin:/usr/bin:/usr/bin:/mingw64/bin:/usr/bin:/c/Users/Ayke/bin:/c/Users/Ayke/.vscode-server/cli/servers/Stable-e54c774e0add60467559eb0d1e229c6452cf8447/server/bin/remote-cli:/c/WINDOWS/system32:/c/WINDOWS:/c/WINDOWS/System32/Wbem:/c/WINDOWS/System32/WindowsPowerShell/v1.0:/c/WINDOWS/System32/OpenSSH:/cmd:/c/Users/Ayke/scoop/apps/mingw-mstorsjo-llvm-ucrt/current/bin:/c/Users/Ayke/scoop/apps/python/current/Scripts:/c/Users/Ayke/scoop/apps/python/current:/c/Users/Ayke/go/bin:/c/Users/Ayke/scoop/shims:/c/Users/Ayke/AppData/Local/Microsoft/WindowsApps:/usr/bin/vendor_perl:/usr/bin/core_perl)
Also, some users have been confused by the error message even though in
most cases it is harmless and can be ignored.
This directive caused the code to be put in a non-executable area on
Windows which caused a segmentation fault. This patch fixes the issue by
removing `.section` directives, fixing windows/arm64 support.
A few small changes were needed to make this work. In particular, I
found a critical bug (see the previous commit) that needed to be fixed
to make this work on Windows.
I'm surprised this worked as long as it did, since it looks like the
goroutine stack did not get scanned. Or maybe the RCX register contained
the stack pointer by accident. In any case, it now uses the correct
register (RCX instead of RDI on Windows) for passing the stack pointer
as the first parameter.
Support for GOARCH=wasm was only available for `tinygo build`, not for
any of the other subcommands (`test`, `run`, etc). With this PR, these
subcommands should work again for supported values of GOOS.
This fixes the following error for example:
$ make tinygo-test-wasip1
GOOS=wasip1 GOARCH=wasm /home/ayke/bin/tinygo test cmp compress/lzw compress/zlib [...etc]
cannot resolve packages: GOARCH=wasm but GOOS is unset. Please set GOOS to wasm, wasip1, or wasip2.
make: *** [GNUmakefile:489: tinygo-test-wasip1] Error 1
This adds support for the well-known Boehm GC. It's significantly faster
than our own naive GC and could be used as an alternative on bigger
systems.
In the future, this GC might also be supported on WebAssembly with some
extra work. Right now it's Linux only (though Windows/MacOS shouldn't be
too difficult to add).
For example, with -gc=none and -gc=leaking, no heap needs to be
allocated when initializing the runtime. And some GCs (like -gc=custom)
are responsible for allocating the heap themselves.