wasmtime by default will assume the subcommand is "run" vs one of its
others, but being explicit helps clarify the actual command invoked.
For example, we pass similar looking args to wasmtime and also wasi.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
We don't support these yet so let's just put them in a central location.
Once these functions are supported we can think about how to structure
the code again.
ThinLTO results in a small code size reduction, which is nice
(especially on these very small chips). It also brings us one step
closer to using ThinLTO everywhere.
LLVM wasn't aware that runtime.stackChainStart must be kept live and
can't be optimized away. With this hack, it is forced to consider
stackChainStart live at the time of the stack scan.
This fixes the corruption in https://github.com/tinygo-org/tinygo/issues/3277
This reverts commit 0b3a7280fa and updates
the documentation a little bit to explain the purpose of -gc=none. (I'm
thinking about the attiny10 by the way where defaulting to -gc=none
makes sense).
- Use compiler-rt and picolibc instead of avr-libc.
- Use ld.lld instead of avr-ld (or avr-gcc).
This makes it much easier to get started with TinyGo on AVR because
installing these extra tools (gcc-avr, avr-libc) can be a hassle.
It also opens the door for future improvements such as ThinLTO.
There is a code size increase but I think it's worth it in the long run.
The code size increase can hopefully be reduced with improvements to the
LLVM AVR backend and to compiler-rt.
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.
Unfortunately the calling convention for variadic functions is different from
the calling convention of regular functions on darwin/arm64, and open happens
to be such a variadic function. The syscall package treated it like a regular
function, which resulted in buggy behavior.
This fix introduces a wrapper function. This is the cleanest change I could
come up with.
The GC was originally designed for systems with a fixed amount of
memory, like baremetal systems. Therefore, it just used what it could
and ran a GC cycle when out of memory.
Other systems (like Linux or WebAssembly) are different. In those
systems, it is possible to grow the amount of memory on demand. But the
GC only actually grew the heap when it was really out of memory, not
when it was getting very close to being out of memory.
This patch fixes this by ensuring there is at least 33% headroom for the
GC. This means that programs can allocate around 50% more than what was
live in the last GC cycle. It should fix a performance cliff when a
program is almost, but not entirely, out of memory and the GC has to run
almost every heap allocation.
This documents memory constants. Somewhere, we should document what the
default memory size is (seems 2 pages so 128KB), as that determines the
initial heap size (which is a portion of that).
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This commit adds support for time.NewTimer and time.NewTicker. It also
adds support for the Stop() method on time.Timer, but doesn't (yet) add
support for the Reset() method.
The implementation has been carefully written so that programs that
don't use these timers will normally not see an increase in RAM or
binary size. None of the examples in the drivers repo change as a result
of this commit. This comes at the cost of slightly more complex code and
possibly slower execution of the timers when they are used.
The Go tools only consider lowercase .s files to be assembly files. By
renaming these to uppercase .S files they won't be discovered by the Go
toolchain and listed as the SFiles to be assembled.
There is a difference between .s and .S: only uppercase .S will be
passed through the preprocessor. Doing that is normally safe, and
definitely safe in the case of these files.
Go 1.19 started reformatting code in a way that makes it more obvious
how it will be rendered on pkg.go.dev. It gets it almost right, but not
entirely. Therefore, I had to modify some of the comments so that they
are formatted correctly.
You can see that it works with the following command:
tinygo run -target=simavr ./testdata/recover.go
This also gets the following tests to pass again:
go test -run=Build -target=simavr -v
Adding support for AVR was a bit more compliated because it's also
necessary to save and restore the Y register.
This is a small change to make it easier to support architectures that
need to restore more than just the sp and pc registers. In particular,
it is needed for the AVR architecture that needs to restore the frame
pointer (Y register).
