a04db67ea9
See the following bug: https://bugs.llvm.org/show_bug.cgi?id=42881 I think this is a bug in LLVM, but the code in question wasn't the best code anyway. By fixing this, about 16 bytes of code are saved on ARM chips (and much more on AVR).
96 строки
1,5 КиБ
Go
96 строки
1,5 КиБ
Go
// +build avr
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package runtime
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import (
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"device/avr"
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"machine"
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"unsafe"
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)
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const BOARD = "arduino"
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type timeUnit uint32
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var currentTime timeUnit
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const tickMicros = 1024 * 16384
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// Watchdog timer periods. These can be off by a large margin (hence the jump
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// between 64ms and 125ms which is not an exact double), so don't rely on this
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// for accurate time keeping.
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const (
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WDT_PERIOD_16MS = iota
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WDT_PERIOD_32MS
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WDT_PERIOD_64MS
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WDT_PERIOD_125MS
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WDT_PERIOD_250MS
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WDT_PERIOD_500MS
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WDT_PERIOD_1S
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WDT_PERIOD_2S
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)
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//go:extern _sbss
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var _sbss unsafe.Pointer
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//go:extern _ebss
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var _ebss unsafe.Pointer
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//go:export main
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func main() {
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preinit()
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initAll()
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postinit()
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callMain()
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abort()
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}
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func preinit() {
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// Initialize .bss: zero-initialized global variables.
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ptr := unsafe.Pointer(&_sbss)
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for ptr != unsafe.Pointer(&_ebss) {
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*(*uint32)(ptr) = 0
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ptr = unsafe.Pointer(uintptr(ptr) + 4)
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}
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}
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func postinit() {
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// Enable interrupts after initialization.
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avr.Asm("sei")
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}
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func init() {
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initUART()
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}
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func initUART() {
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machine.UART0.Configure(machine.UARTConfig{})
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}
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func putchar(c byte) {
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machine.UART0.WriteByte(c)
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}
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const asyncScheduler = false
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// Sleep this number of ticks of 16ms.
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//
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// TODO: not very accurate. Improve accuracy by calibrating on startup and every
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// once in a while.
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func sleepTicks(d timeUnit) {
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currentTime += d
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for d != 0 {
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sleepWDT(WDT_PERIOD_16MS)
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d -= 1
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}
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}
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func ticks() timeUnit {
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return currentTime
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}
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func abort() {
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for {
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sleepWDT(WDT_PERIOD_2S)
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}
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}
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