mirror of
https://github.com/tinygo-org/tinygo.git
synced 2026-08-03 02:27:48 +00:00
Ayke van Laethem
a2d0f79be3
So far, we've pretended to be js/wasm in baremetal targets to make the
stdlib happy. Unfortunately, this has various problems because
syscall/js (a dependency of many stdlib packages) thinks it can do JS
calls, and emulating them gets quite hard with all changes to the
syscall/js packages in Go 1.12.
This commit does a few things:
* It lets baremetal targets pretend to be linux/arm instead of
js/wasm.
* It lets the loader only select particular packages from the src
overlay, instead of inserting them just before GOROOT. This makes it
possible to pick which packages to overlay for a given target.
* It adds a baremetal-only syscall package that stubs out almost all
syscalls.
47 lines
924 B
Go
47 lines
924 B
Go
// +build cortexm
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package runtime
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import (
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"unsafe"
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"device/arm"
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)
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const GOARCH = "arm"
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// The bitness of the CPU (e.g. 8, 32, 64).
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const TargetBits = 32
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//go:extern _heap_start
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var heapStartSymbol unsafe.Pointer
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//go:extern _heap_end
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var heapEndSymbol unsafe.Pointer
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//go:extern _globals_start
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var globalsStartSymbol unsafe.Pointer
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//go:extern _globals_end
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var globalsEndSymbol unsafe.Pointer
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//go:extern _stack_top
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var stackTopSymbol unsafe.Pointer
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var (
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heapStart = uintptr(unsafe.Pointer(&heapStartSymbol))
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heapEnd = uintptr(unsafe.Pointer(&heapEndSymbol))
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globalsStart = uintptr(unsafe.Pointer(&globalsStartSymbol))
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globalsEnd = uintptr(unsafe.Pointer(&globalsEndSymbol))
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stackTop = uintptr(unsafe.Pointer(&stackTopSymbol))
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)
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// Align on word boundary.
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func align(ptr uintptr) uintptr {
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return (ptr + 3) &^ 3
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}
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func getCurrentStackPointer() uintptr {
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return arm.ReadRegister("sp")
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}
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