Martin Möhrmann <******@****.***> 1524859139 +0200

	// amd64:`.*runtime\.mapclear`
	// amd64:-`.*runtime\.mapiterinit`
	for k := range m {
		delete(m, k)
	}
}

func MapClearNotReflexive(m map[float64]int) {
	// amd64:`.*runtime\.mapiterinit`
	// amd64:-`.*runtime\.mapclear`
	for k := range m {
		delete(m, k)
	}
}

func MapClearInterface(m map[interface{}]int) {
	// amd64:`.*runtime\.mapiterinit`
	// amd64:-`.*runtime\.mapclear`
	for k := range m {

}

// mapRangeClear constructs a call to runtime.mapclear for the map range idiom.
func mapRangeClear(nrange *ir.RangeStmt) ir.Node {
	m := nrange.X
	origPos := ir.SetPos(m)
	defer func() { base.Pos = origPos }()

	return mapClear(m, reflectdata.RangeMapRType(base.Pos, nrange))
}

// mapClear constructs a call to runtime.mapclear for the map m.
func mapClear(m, rtyp ir.Node) ir.Node {
	t := m.Type()

	{"runtime.mapiterinit", 1},
	{"runtime.mapdelete", 1},
	{"runtime.mapdelete_fast32", 1},
	{"runtime.mapdelete_fast64", 1},
	{"runtime.mapdelete_faststr", 1},
	{"runtime.mapiternext", 1},
	{"runtime.mapclear", 1},
	{"runtime.makechan64", 1},
	{"runtime.makechan", 1},
	{"runtime.chanrecv1", 1},
	{"runtime.chanrecv2", 1},
	{"runtime.chansend1", 1},
	{"runtime.closechan", 1},
	{"runtime.chanlen", 1},

// Do not remove or change the type signature.
// See go.dev/issue/67401.
//
//go:linkname mapclear
func mapclear(t *maptype, h *hmap) {
	if raceenabled && h != nil {
		callerpc := getcallerpc()
		pc := abi.FuncPCABIInternal(mapclear)
		racewritepc(unsafe.Pointer(h), callerpc, pc)
	}

	if h == nil || h.count == 0 {
		return
	}

	if h.flags&hashWriting != 0 {
		fatal("concurrent map writes")

func mapdelete_fast64(mapType *byte, hmap map[any]any, key uint64)
func mapdelete_faststr(mapType *byte, hmap map[any]any, key string)
func mapiternext(hiter *any)
func mapclear(mapType *byte, hmap map[any]any)

// *byte is really *runtime.Type
func makechan64(chanType *byte, size int64) (hchan chan any)
func makechan(chanType *byte, size int) (hchan chan any)

	{"mapiterinit", funcTag, 91},
	{"mapdelete", funcTag, 91},
	{"mapdelete_fast32", funcTag, 92},
	{"mapdelete_fast64", funcTag, 93},
	{"mapdelete_faststr", funcTag, 94},
	{"mapiternext", funcTag, 95},
	{"mapclear", funcTag, 96},
	{"makechan64", funcTag, 98},
	{"makechan", funcTag, 99},
	{"chanrecv1", funcTag, 101},
	{"chanrecv2", funcTag, 102},
	{"chansend1", funcTag, 104},
	{"closechan", funcTag, 105},

			return n
		}
		// If n == nil, we are clearing an array which takes zero memory, do nothing.
		return ir.NewBlockStmt(n.Pos(), nil)
	case typ.IsMap():
		return mapClear(n.X, reflectdata.TypePtrAt(n.X.Pos(), n.X.Type()))
	}
	panic("unreachable")
}

// walkClose walks an OCLOSE node.
func walkClose(n *ir.UnaryExpr, init *ir.Nodes) ir.Node {

	m[key2] += "1"
	if n2 := m[key2]; n2 != "1" {
		t.Errorf("appended '1' to empty (nil) string, got %s", n2)
	}
}

// TestIncrementAfterBulkClearKeyStringValueInt tests that map bulk
// deletion (mapclear) still works as expected. Note that it was not
// affected by Issue 25936.
func TestIncrementAfterBulkClearKeyStringValueInt(t *testing.T) {
	const key1 = ""
	const key2 = "x"

	m := make(map[string]int)

func (v Value) Clear() {
	switch v.Kind() {
	case Slice:
		sh := *(*unsafeheader.Slice)(v.ptr)
		st := (*sliceType)(unsafe.Pointer(v.typ()))
		typedarrayclear(st.Elem, sh.Data, sh.Len)
	case Map:
		mapclear(v.typ(), v.pointer())
	default:
		panic(&ValueError{"reflect.Value.Clear", v.Kind()})
	}
}

// Append appends the values x to a slice s and returns the resulting slice.