Found while working on the PineTime. For some reason it still kind of
works in most cases, but I was hitting this issue when interacting with
two different I2C devices (the touch sensor and the BMA421).
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/
The Linux artifacts have clear names (linux-amd64-double-zipped etc),
but the MacOS and Windows ones didn't. This patch renames these artifact
names to be more readable, especially when downloading the artifacts.
These are some major or breaking changes:
- Reflect support got improved a lot.
- Interrupts became more strict: heap allocations an blocking
operations, which have always been undefined behavior, now result in
a panic.
- `//go:wasmimport` was added
- various new flags were added to `tinygo test`
- the source location for panics is printed in the `-monitor` output
The regular port access is around 4 cycles, instead of the usual 2
cycles for a store instruction on Cortex-M0+. The IOBUS however is
faster, I didn't measure exactly but I guess it's 2 cycles as expected.
This fixes a bug in the WS2812 driver that only happens on samd21 chips:
https://github.com/tinygo-org/drivers/issues/540
I didn't add this method in the initial PR.
Also, I found that a few of my assumptions were incorrect. I've changed
the code that configures the pin to make input (floating and pullup)
actually work. These chips really are quite different from all the older
AVRs.
If a pointer value was xor'ed with a value other than 0, it would not
have been run at runtime but instead would fall through to the generic
integer operations. This would likely result in a "cannot convert
pointer to integer" panic.
This commit fixes this subtle case.
This is just support for the chip, no boards are currently supported.
However, you can use this target on a custom board.
Notes:
- This required a new runtime and machine implementation, because the
hardware is actually very different (and much nicer than older
AVRs!).
- I had to update gen-device-avr to support this chip. This also
affects the generated output of other AVRs, but I checked all chips
we support and there shouldn't be any backwards incompatible
changes.
- I did not implement peripherals like UART, I2C, SPI, etc because I
don't need them. That is left to do in the future.
You can flash these chips with only a UART and a 1kOhm resistor, which
is really nice (no special hardware needed). Here is the program I've
used for this purpose: https://pypi.org/project/pymcuprog/
This refactors gen-device-avr to output two different formats: one for
all the existing AVR chips (that don't really have the concept of a
peripheral, just a bunch of registers), and one for all the new chips
like the ATtiny1616 (tinyAVR 1-series and 2-series) that have
peripherals like the Cortex-M chips with type structs and instances.
I checked the generated code for all the AVR chips we have support for
(atmega1280, atmega1284p, atmega2560, atmega328p, atmega32u4, attiny85)
and while the generated Go code did change, it looks safe to me.
This is a small change that's not really important in itself, but it
avoids duplicate errors in a future commit that adds error messages to
//go:wasmimport.
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.
