N, _ := NewModulusFromBig(n)
	A := NewNat().setBig(a).ExpandFor(N)
	B := NewNat().setBig(b).ExpandFor(N)

	if A.Mul(B, N).IsZero() != 1 {
		t.Error("a * b mod (a * b) != 0")
	}

	i := new(big.Int).ModInverse(a, b)
	N, _ = NewModulusFromBig(b)
	A = NewNat().setBig(a).ExpandFor(N)
	I := NewNat().setBig(i).ExpandFor(N)
	one := NewNat().setBig(big.NewInt(1)).ExpandFor(N)

	if A.Mul(I, N).Equal(one) != 1 {

		}

		// Move all the stores to the root.
		for i := int64(0); i < n; i++ {
			v := a[i].store
			if v == root {
				v.Aux = cv.Type // widen store type
				v.Pos = pos
				v.SetArg(0, ptr)
				v.SetArg(1, cv)
				v.SetArg(2, mem)
			} else {
				clobber(v)
				v.Type = types.Types[types.TBOOL] // erase memory type
			}
		}
		return true
	}

				if p.Controls[0] != a {
					continue
				}
				if e.i == 0 {
					if ct == nil {
						ct = f.ConstBool(f.Config.Types.Bool, true)
					}
					v.SetArg(i, ct)
				} else {
					if cf == nil {
						cf = f.ConstBool(f.Config.Types.Bool, false)
					}
					v.SetArg(i, cf)
				}
			}
		}
	}

	// Step 2: Redirect control flow around known branches.
	// p:
	//   ... goto b ...
	// b: <- p ...

			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

			// deferreturn must itself be a resumption
			// point so it gets a target PC.
			s.Prog(wasm.ARESUMEPOINT)
		}
		if v.Op == ssa.OpWasmLoweredClosureCall {
			getValue64(s, v.Args[1])
			setReg(s, wasm.REG_CTXT)
		}
		if call, ok := v.Aux.(*ssa.AuxCall); ok && call.Fn != nil {
			sym := call.Fn
			p := s.Prog(obj.ACALL)
			p.To = obj.Addr{Type: obj.TYPE_MEM, Name: obj.NAME_EXTERN, Sym: sym}

		}
	}
}

func testDeferPtrsGoexit(c chan int, i int) {
	var y int
	defer func() {
		c <- y
	}()
	defer setBig(&y, 42, bigBuf{})
	useStackAndCall(i, Goexit)
}

func setBig(p *int, x int, b bigBuf) {
	*p = x
}

// TestDeferPtrsPanic is like TestDeferPtrsGoexit, but it's using panic instead

		for b, r := range newmemphis {
			fmt.Printf("after b=%s, rewrite=%s\n", b, r.String())
		}
	}

	// Apply collected rewrites.
	for _, r := range newmemphis {
		for _, rw := range r.rewrites {
			rw.v.SetArg(rw.i, r.after)
		}
	}

	// Rewrite backedges to include reschedule checks.
	for _, emc := range tofixBackedges {
		e := emc.e
		headerMemPhi := emc.m
		h := e.b
		i := e.i
		p := h.Preds[i]

func (x *Nat) set(y *Nat) *Nat {
	x.reset(len(y.limbs))
	copy(x.limbs, y.limbs)
	return x
}

// setBig assigns x = n, optionally resizing n to the appropriate size.
//
// The announced length of x is set based on the actual bit size of the input,
// ignoring leading zeroes.
func (x *Nat) setBig(n *big.Int) *Nat {
	limbs := n.Bits()
	x.reset(len(limbs))
	for i := range limbs {
		x.limbs[i] = uint(limbs[i])

func mdestroy(mp *m) {
}

func sigtramp()

type sigactiont struct {
	sa_sigaction uintptr
	sa_mask      sigset
	sa_flags     int32
}

//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

	_SIG_SETMASK = 3
	_SS_DISABLE  = 4
)

//extern SigTabTT runtime·sigtab[];

type sigset uint32

var sigset_all = ^sigset(0)

//go:nosplit
//go:nowritebarrierrec
func setsig(i uint32, fn uintptr) {
	var sa usigactiont
	sa.sa_flags = _SA_SIGINFO | _SA_ONSTACK | _SA_RESTART
	sa.sa_mask = ^uint32(0)