}

func sysHugePageCollapseOS(v unsafe.Pointer, n uintptr) {
}

// Don't split the stack as this function may be invoked without a valid G,
// which prevents us from allocating more stack.
//
//go:nosplit
func sysFreeOS(v unsafe.Pointer, n uintptr) {
	munmap(v, n)
}

func sysFaultOS(v unsafe.Pointer, n uintptr) {
	mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_PRIVATE|_MAP_FIXED, -1, 0)
}

}

func sysHugePageCollapseOS(v unsafe.Pointer, n uintptr) {
}

// Don't split the stack as this function may be invoked without a valid G,
// which prevents us from allocating more stack.
//
//go:nosplit
func sysFreeOS(v unsafe.Pointer, n uintptr) {
	munmap(v, n)
}

func sysFaultOS(v unsafe.Pointer, n uintptr) {
	mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_PRIVATE|_MAP_FIXED, -1, 0)
}

}

func sysHugePageCollapseOS(v unsafe.Pointer, n uintptr) {
}

// Don't split the stack as this function may be invoked without a valid G,
// which prevents us from allocating more stack.
//
//go:nosplit
func sysFreeOS(v unsafe.Pointer, n uintptr) {
	munmap(v, n)
}

func sysFaultOS(v unsafe.Pointer, n uintptr) {
	mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_PRIVATE|_MAP_FIXED, -1, 0)
}

func sysHugePageCollapseOS(v unsafe.Pointer, n uintptr) {
}

// Don't split the stack as this function may be invoked without a valid G,
// which prevents us from allocating more stack.
//
//go:nosplit
func sysFreeOS(v unsafe.Pointer, n uintptr) {
	r := stdcall3(_VirtualFree, uintptr(v), 0, _MEM_RELEASE)
	if r == 0 {
		print("runtime: VirtualFree of ", n, " bytes failed with errno=", getlasterror(), "\n")

	bloc = memRound(firstmoduledata.end)
	blocMax = bloc
}

func sysAllocOS(n uintptr) unsafe.Pointer {
	lock(&memlock)
	p := memAlloc(n)
	memCheck()
	unlock(&memlock)
	return p
}

func sysFreeOS(v unsafe.Pointer, n uintptr) {
	lock(&memlock)
	if uintptr(v)+n == bloc {
		// Address range being freed is at the end of memory,
		// so record a new lower value for end of memory.

	// any errors.
	madvise(v, n, _MADV_COLLAPSE)
}

// Don't split the stack as this function may be invoked without a valid G,
// which prevents us from allocating more stack.
//
//go:nosplit
func sysFreeOS(v unsafe.Pointer, n uintptr) {
	munmap(v, n)
}

func sysFaultOS(v unsafe.Pointer, n uintptr) {
	mprotect(v, n, _PROT_NONE)
	madvise(v, n, _MADV_DONTNEED)
}

// which prevents us from allocating more stack.
//
//go:nosplit
func sysFree(v unsafe.Pointer, n uintptr, sysStat *sysMemStat) {
	sysStat.add(-int64(n))
	gcController.mappedReady.Add(-int64(n))
	sysFreeOS(v, n)
}

// sysFault transitions a memory region from Ready to Reserved. It
// marks a region such that it will always fault if accessed. Used only for
// debugging the runtime.
//

		for l := 0; l < summaryLevels; l++ {
			sysFreeOS(unsafe.Pointer(&p.summary[l][0]), uintptr(cap(p.summary[l]))*pallocSumBytes)
		}
	} else {
		resSize := uintptr(0)
		for _, s := range p.summary {
			resSize += uintptr(cap(s)) * pallocSumBytes
		}
		sysFreeOS(unsafe.Pointer(&p.summary[0][0]), alignUp(resSize, physPageSize))
	}

	// Free extra data structures.

		// re-reserve the aligned sub-region. This may race,
		// so we may have to try again.
		sysFreeOS(unsafe.Pointer(p), size+align)
		p = alignUp(p, align)
		p2 := sysReserve(unsafe.Pointer(p), size)
		if p != uintptr(p2) {
			// Must have raced. Try again.
			sysFreeOS(p2, size)
			if retries++; retries == 100 {
				throw("failed to allocate aligned heap memory; too many retries")
			}