54169c714f
This simplifies adding more baremetal targets, like a GameBoy Advance, or baremetal x86 for unikernels.
39 строки
1,2 КиБ
Go
39 строки
1,2 КиБ
Go
// +build gc.conservative
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// +build !baremetal
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package runtime
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import (
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"unsafe"
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)
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//go:extern runtime.stackChainStart
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var stackChainStart *stackChainObject
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type stackChainObject struct {
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parent *stackChainObject
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numSlots uintptr
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}
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// markStack marks all root pointers found on the stack.
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//
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// This implementation is conservative and relies on the compiler inserting code
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// to manually push/pop stack objects that are stored in a linked list starting
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// with stackChainStart. Manually keeping track of stack values is _much_ more
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// expensive than letting the compiler do it and it inhibits a few important
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// optimizations, but it has the big advantage of being portable to basically
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// any ISA, including WebAssembly.
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func markStack() {
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stackObject := stackChainStart
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for stackObject != nil {
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start := uintptr(unsafe.Pointer(stackObject)) + unsafe.Sizeof(uintptr(0))*2
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end := start + stackObject.numSlots*unsafe.Alignof(uintptr(0))
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markRoots(start, end)
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stackObject = stackObject.parent
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}
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}
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// trackPointer is a stub function call inserted by the compiler during IR
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// construction. Calls to it are later replaced with regular stack bookkeeping
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// code.
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func trackPointer(ptr unsafe.Pointer)
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