// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

//go:build arm64 && darwin && !ios

package cpu

import _ "unsafe" // for linkname

func osInit() {
	ARM64.HasATOMICS = sysctlEnabled([]byte("hw.optional.armv8_1_atomics\x00"))
	ARM64.HasCRC32 = sysctlEnabled([]byte("hw.optional.armv8_crc32\x00"))
	ARM64.HasSHA512 = sysctlEnabled([]byte("hw.optional.armv8_2_sha512\x00"))

//
//go:noescape
func write1(fd uintptr, p unsafe.Pointer, n int32) int32

//go:noescape
func open(name *byte, mode, perm int32) int32

// return value is only set on linux to be used in osinit().
func madvise(addr unsafe.Pointer, n uintptr, flags int32) int32

// exitThread terminates the current thread, writing *wait = freeMStack when
// the stack is safe to reclaim.
//
//go:noescape

//
//go:noescape
func write1(fd uintptr, p unsafe.Pointer, n int32) int32

//go:noescape
func open(name *byte, mode, perm int32) int32

// return value is only set on linux to be used in osinit().
func madvise(addr unsafe.Pointer, n uintptr, flags int32) int32

// exitThread terminates the current thread, writing *wait = freeMStack when
// the stack is safe to reclaim.
//
//go:noescape

}

// Called to initialize a new m (including the bootstrap m).
// Called on the new thread, cannot allocate memory.
func minit() {
}

// Called from dropm to undo the effect of an minit.
func unminit() {
}

// Called from exitm, but not from drop, to undo the effect of thread-owned
// resources in minit, semacreate, or elsewhere. Do not take locks after calling this.
func mdestroy(mp *m) {
}

// wasm has no signals

// Called on the new thread, can not allocate memory.
func minit() {
	getg().m.procid = uint64(getthrid())
	minitSignals()
}

// Called from dropm to undo the effect of an minit.
//
//go:nosplit
func unminit() {
	unminitSignals()
	getg().m.procid = 0
}

// Called from exitm, but not from drop, to undo the effect of thread-owned
// resources in minit, semacreate, or elsewhere. Do not take locks after calling this.

	}
	return 0
}

//go:nosplit
func semawakeup(mp *m) {
	if sem_post((*semt)(unsafe.Pointer(mp.waitsema))) != 0 {
		throw("sem_post")
	}
}

func osinit() {
	// Call miniterrno so that we can safely make system calls
	// before calling minit on m0.
	miniterrno()

	ncpu = int32(sysconf(__SC_NPROCESSORS_ONLN))
	physPageSize = sysconf(__SC_PAGE_SIZE)
}

// created thread. On NetBSD, a new thread inherits the signal stack
// of the creating thread. That confuses minit, so we remove that
// signal stack here before calling the regular mstart. It's a bit
// baroque to remove a signal stack here only to add one in minit, but
// it's a simple change that keeps NetBSD working like other OS's.
// At this point all signals are blocked, so there is no race.
//

// Called on the new thread, cannot allocate memory.
func minit() {
	if atomic.Load(&exiting) != 0 {
		exits(&emptystatus[0])
	}
	// Mask all SSE floating-point exceptions
	// when running on the 64-bit kernel.
	setfpmasks()
}

// Called from dropm to undo the effect of an minit.
func unminit() {
}

func getPageSize() uintptr {
	n := int32(sysconf(__SC_PAGESIZE))
	if n <= 0 {
		return 0
	}
	return uintptr(n)
}

func osinit() {
	// Call miniterrno so that we can safely make system calls
	// before calling minit on m0.
	asmcgocall(unsafe.Pointer(abi.FuncPCABI0(miniterrno)), unsafe.Pointer(&libc____errno))

	ncpu = getncpu()
	if physPageSize == 0 {
		physPageSize = getPageSize()

}

// sigsetAllExiting is used by sigblock(true) when a thread is
// exiting.
var sigsetAllExiting = func() sigset {
	res := sigset_all

	// Apply GOOS-specific overrides here, rather than in osinit,
	// because osinit may be called before sigsetAllExiting is
	// initialized (#51913).
	if GOOS == "linux" && iscgo {
		// #42494 glibc and musl reserve some signals for
		// internal use and require they not be blocked by