// the calculated store chain is good only for this block.
		for _, v := range b.Values {
			if v.Op != OpPhi && v.Op != OpInitMem && v.Type.IsMemory() {
				nextMem[v.MemoryArg().ID] = v
			}
		}

		// Add edges to enforce that any load must come before the following store.
		for _, v := range b.Values {
			if v.Op == OpPhi || v.Type.IsMemory() {
				continue
			}
			w := v.MemoryArg()
			if w == nil {
				continue

			}

			for i, arg := range v.Args {
				if arg == nil {
					f.Fatalf("value %s has nil arg", v.LongString())
				}
				if v.Op != OpPhi {
					// For non-Phi ops, memory args must be last, if present
					if arg.Type.IsMemory() && i != len(v.Args)-1 {
						f.Fatalf("value %s has non-final memory arg (%d < %d)", v.LongString(), i, len(v.Args)-1)
					}

		e := emc.e
		h := e.b

		// find the phi function for the memory input at "h", if there is one.
		var headerMemPhi *Value // look for header mem phi

		for _, v := range h.Values {
			if v.Op == OpPhi && v.Type.IsMemory() {
				headerMemPhi = v
			}
		}

		if headerMemPhi == nil {
			// if the header is nil, make a trivial phi from the dominator
			mem0 := memDefsAtBlockEnds[idom[h.ID].ID]

		for k := range localAddrs {
			delete(localAddrs, k)
		}
		stores = stores[:0]
		for _, v := range b.Values {
			if v.Op == OpPhi {
				// Ignore phis - they will always be first and can't be eliminated
				continue
			}
			if v.Type.IsMemory() {
				stores = append(stores, v)
				for _, a := range v.Args {

				dest := edge.b
				destVisited := t.visitedBlock[dest.ID]

				// mark edge as visited
				t.visited[edge] = true
				t.visitedBlock[dest.ID] = true
				for _, val := range dest.Values {
					if val.Op == OpPhi || !destVisited {
						t.visitValue(val)
					}
				}
				// propagates constants facts through CFG, taking condition test
				// into account
				if !destVisited {
					t.propagate(dest)
				}
			}

			Goto("checkPtr")),
		Bloc("b2",
			Valu("ptr2", OpAddr, ptrType, 0, nil, "sb"),
			Goto("checkPtr")),
		// both ptr1 and ptr2 are guaranteed non-nil here
		Bloc("checkPtr",
			Valu("phi", OpPhi, ptrType, 0, nil, "ptr1", "ptr2"),
			Valu("bool2", OpIsNonNil, c.config.Types.Bool, 0, nil, "phi"),
			If("bool2", "extra", "exit")),
		Bloc("extra",
			Goto("exit")),
		Bloc("exit",
			Exit("mem")))

// The returned value, if non-nil, will be memory-typed (or a tuple with a memory-typed second part).
// Otherwise, nil is returned.
func (v *Value) MemoryArg() *Value {
	if v.Op == OpPhi {
		v.Fatalf("MemoryArg on Phi")
	}
	na := len(v.Args)
	if na == 0 {
		return nil
	}
	if m := v.Args[na-1]; m.Type.IsMemory() {
		return m
	}
	return nil
}

			}
		}
	}

	for changed := true; changed; {
		changed = false
		for _, b := range f.Blocks {
			for _, v := range b.Values {
				// phis whose arguments are all non-nil
				// are non-nil
				if v.Op == OpPhi {
					argsNonNil := true
					for _, a := range v.Args {
						if nonNilValues[a.ID] == nil {
							argsNonNil = false
							break
						}
					}
					if argsNonNil {
						if nonNilValues[v.ID] == nil {

// with nxt being (Add inc ind).
// If it can't parse the induction variable correctly, it returns (nil, nil, nil).
func parseIndVar(ind *Value) (min, inc, nxt *Value) {
	if ind.Op != OpPhi {
		return
	}

	if n := ind.Args[0]; (n.Op == OpAdd64 || n.Op == OpAdd32 || n.Op == OpAdd16 || n.Op == OpAdd8) && (n.Args[0] == ind || n.Args[1] == ind) {
		min, nxt = ind.Args[1], n

			live.addAll(s.live[b.ID])

			// Propagate backwards to the start of the block
			phis = phis[:0]
			for i := len(b.Values) - 1; i >= 0; i-- {
				v := b.Values[i]
				live.remove(v.ID)
				if v.Op == OpPhi {
					// Save phi for later.
					// Note: its args might need a stack slot even though
					// the phi itself doesn't. So don't use needSlot.
					if !v.Type.IsMemory() && !v.Type.IsVoid() {
						phis = append(phis, v)