func mdestroy(mp *m) {
}

func sigtramp()

type sigactiont struct {
	sa_handler uintptr
	sa_flags   int32
	sa_mask    sigset
}

// See os_freebsd2.go, os_freebsd_amd64.go for setsig function

//go:nosplit
//go:nowritebarrierrec
func setsigstack(i uint32) {
	var sa sigactiont
	sigaction(i, nil, &sa)
	if sa.sa_flags&_SA_ONSTACK != 0 {
		return
	}
	sa.sa_flags |= _SA_ONSTACK

// resources in minit, semacreate, or elsewhere. Do not take locks after calling this.
func mdestroy(mp *m) {
}

func sigtramp()

//go:nosplit
//go:nowritebarrierrec
func setsig(i uint32, fn uintptr) {
	var sa sigactiont

	sa.sa_flags = _SA_SIGINFO | _SA_ONSTACK | _SA_RESTART
	sa.sa_mask = sigset_all

	for _, b := range f.Blocks {
		for _, v := range b.Values {
			for i, a := range v.Args {
				if a.Op == OpSPanchored || opcodeTable[a.Op].nilCheck {
					v.SetArg(i, a.Args[0])
				}
			}
		}
		for i, c := range b.ControlValues() {
			if c.Op == OpSPanchored || opcodeTable[c.Op].nilCheck {
				b.ReplaceControl(i, c.Args[0])
			}
		}
	}

				// Only set arguments that have been resolved.
				// For very wide CFGs, this significantly speeds up phi resolution.
				// See golang.org/issue/8225.
				if w := values[v.AuxInt]; w.Op != ssa.OpUnknown {
					v.SetArg(i, w)
				}
			}
		}

		// Walk children in dominator tree.
		for c := s.tree[b.ID].firstChild; c != nil; c = s.tree[c.ID].sibling {
			stk = append(stk, stackEntry{b: c})
		}
	}
}

}

func (v *Value) AddArgs(a ...*Value) {
	if v.Args == nil {
		v.resetArgs() // use argstorage
	}
	v.Args = append(v.Args, a...)
	for _, x := range a {
		x.Uses++
	}
}
func (v *Value) SetArg(i int, w *Value) {
	v.Args[i].Uses--
	v.Args[i] = w
	w.Uses++
}
func (v *Value) SetArgs1(a *Value) {
	v.resetArgs()
	v.AddArg(a)
}
func (v *Value) SetArgs2(a, b *Value) {
	v.resetArgs()

	return int32(r), int32(err)
}

const (
	_si_max_size    = 128
	_sigev_max_size = 64
)

//go:nosplit
//go:nowritebarrierrec
func setsig(i uint32, fn uintptr) {
	var sa sigactiont
	sa.sa_flags = _SA_SIGINFO | _SA_ONSTACK | _SA_RESTORER | _SA_RESTART
	sigfillset(&sa.sa_mask)
	// Although Linux manpage says "sa_restorer element is obsolete and