type scase struct {
	c    *hchan         // chan
	elem unsafe.Pointer // data element
}

var (
	chansendpc = abi.FuncPCABIInternal(chansend)
	chanrecvpc = abi.FuncPCABIInternal(chanrecv)
)

func selectsetpc(pc *uintptr) {
	*pc = getcallerpc()
}

func sellock(scases []scase, lockorder []uint16) {
	var c *hchan
	for _, o := range lockorder {

			if fwdSig[i] != _SIG_DFL && fwdSig[i] != _SIG_IGN {
				setsigstack(i)
			} else if fwdSig[i] == _SIG_IGN {
				sigInitIgnored(i)
			}
			continue
		}

		handlingSig[i] = 1
		setsig(i, abi.FuncPCABIInternal(sighandler))
	}
}

//go:nosplit
//go:nowritebarrierrec
func sigInstallGoHandler(sig uint32) bool {
	// For some signals, we respect an inherited SIG_IGN handler

// be used as the second word of an interface value.
func convT(t *_type, v unsafe.Pointer) unsafe.Pointer {
	if raceenabled {
		raceReadObjectPC(t, v, getcallerpc(), abi.FuncPCABIInternal(convT))
	}
	if msanenabled {
		msanread(v, t.Size_)
	}
	if asanenabled {
		asanread(v, t.Size_)
	}
	x := mallocgc(t.Size_, t, true)
	typedmemmove(t, x, v)
	return x
}

	// should not be used". x86_64 kernel requires it. Only use it on
	// x86.
	if GOARCH == "386" || GOARCH == "amd64" {
		sa.sa_restorer = abi.FuncPCABI0(sigreturn__sigaction)
	}
	if fn == abi.FuncPCABIInternal(sighandler) { // abi.FuncPCABIInternal(sighandler) matches the callers in signal_unix.go
		if iscgo {
			fn = abi.FuncPCABI0(cgoSigtramp)
		} else {
			fn = abi.FuncPCABI0(sigtramp)
		}
	}
	sa.sa_handler = fn

		throw("unreachable")
	}

	if debugChan {
		print("chansend: chan=", c, "\n")
	}

	if raceenabled {
		racereadpc(c.raceaddr(), callerpc, abi.FuncPCABIInternal(chansend))
	}

	// Fast path: check for failed non-blocking operation without acquiring the lock.
	//
	// After observing that the channel is not closed, we observe that the channel is

// asyncPreempt call.
var asyncPreemptStack = ^uintptr(0)

func init() {
	f := findfunc(abi.FuncPCABI0(asyncPreempt))
	total := funcMaxSPDelta(f)
	f = findfunc(abi.FuncPCABIInternal(asyncPreempt2))
	total += funcMaxSPDelta(f)
	// Add some overhead for return PCs, etc.
	asyncPreemptStack = uintptr(total) + 8*goarch.PtrSize
	if asyncPreemptStack > stackNosplit {

}

func (t rtype) textOff(off textOff) unsafe.Pointer {
	if off == -1 {
		// -1 is the sentinel value for unreachable code.
		// See cmd/link/internal/ld/data.go:relocsym.
		return unsafe.Pointer(abi.FuncPCABIInternal(unreachableMethod))
	}
	base := uintptr(unsafe.Pointer(t.Type))
	var md *moduledata
	for next := &firstmoduledata; next != nil; next = next.next {
		if base >= next.types && base < next.etypes {
			md = next

func IsFuncPCIntrinsic(n *CallExpr) bool {
	if n.Op() != OCALLFUNC || n.Fun.Op() != ONAME {
		return false
	}
	fn := n.Fun.(*Name).Sym()
	return (fn.Name == "FuncPCABI0" || fn.Name == "FuncPCABIInternal") &&
		fn.Pkg.Path == "internal/abi"
}

// IsIfaceOfFunc inspects whether n is an interface conversion from a direct
// reference of a func. If so, it returns referenced Func; otherwise nil.
//

// See the doc comment for deferrangefunc for details.
func deferprocat(fn func(), frame any) {
	head := frame.(*atomic.Pointer[_defer])
	if raceenabled {
		racewritepc(unsafe.Pointer(head), getcallerpc(), abi.FuncPCABIInternal(deferprocat))
	}
	d1 := newdefer()
	d1.fn = fn
	for {
		d1.link = head.Load()
		if d1.link == badDefer() {
			throw("defer after range func returned")
		}
		if head.CompareAndSwap(d1.link, d1) {

			count = uint64(stk[0])
			stk = []uint64{
				// gentraceback guarantees that PCs in the
				// stack can be unconditionally decremented and
				// still be valid, so we must do the same.
				uint64(abi.FuncPCABIInternal(lostProfileEvent) + 1),
			}
		}
		b.m.lookup(stk, tag).count += int64(count)
	}

	if len(tags) != 0 {
		return fmt.Errorf("mismatched profile records and tags")
	}
	return nil
}