// A typeSwitch walks a type switch.
type typeSwitch struct {
	// Temporary variables (i.e., ONAMEs) used by type switch dispatch logic:
	srcName  ir.Node // value being type-switched on
	hashName ir.Node // type hash of the value being type-switched on
	okName   ir.Node // boolean used for comma-ok type assertions
	itabName ir.Node // itab value to use for first word of non-empty interface
}

type typeClause struct {
	hash uint32

	// a pointer/scalar bitmap. We also reserve space for a dummy _type that
	// refers to the bitmap. The PtrBytes field of the dummy _type indicates how
	// many of those bits are valid.
	return userArenaChunkBytes/goarch.PtrSize/8 + unsafe.Sizeof(_type{})
}

type userArena struct {
	// full is a list of full chunks that have not enough free memory left, and

			// Allocate space to unroll the gcprog. This space will consist of
			// a dummy _type value and the unrolled gcprog. The dummy _type will
			// refer to the bitmap, and the mspan will refer to the dummy _type.
			if span.spanclass.sizeclass() != 0 {
				throw("GCProg for type that isn't large")
			}
			spaceNeeded := alignUp(unsafe.Sizeof(_type{}), goarch.PtrSize)
			heapBitsOff := spaceNeeded

}
func nilinterequal(p, q unsafe.Pointer) bool {
	x := *(*eface)(p)
	y := *(*eface)(q)
	return x._type == y._type && efaceeq(x._type, x.data, y.data)
}
func efaceeq(t *_type, x, y unsafe.Pointer) bool {
	if t == nil {
		return true
	}
	eq := t.Equal
	if eq == nil {
		panic(errorString("comparing uncomparable type " + toRType(t).string()))
	}
	if isDirectIface(t) {

	}
}

// cgoCheckTypedBlock checks the block of memory at src, for up to size bytes,
// and throws if it finds an unpinned Go pointer. The type of the memory is typ,
// and src is off bytes into that type.
//
//go:nosplit
//go:nowritebarrier
func cgoCheckTypedBlock(typ *_type, src unsafe.Pointer, off, size uintptr) {
	// Anything past typ.PtrBytes is not a pointer.
	if typ.PtrBytes <= off {
		return
	}

	mask := v.mask
	if multipin {
		mask <<= 1
	}
	if val {
		atomic.Or8(v.bytep, mask)
	} else {
		atomic.And8(v.bytep, ^mask)
	}
}

// pinnerBits is the same type as gcBits but has different methods.
type pinnerBits gcBits

// ofObject returns the pinState of the n'th object.
// nosplit, because it's called by isPinned, which is nosplit
//
//go:nosplit

// have been serialized so far, most recently used first.
// Note: when a bucket overflows we may end up
// serializing a type more than once. That's ok.
const (
	typeCacheBuckets = 256
	typeCacheAssoc   = 4
)

type typeCacheBucket struct {
	t [typeCacheAssoc]*_type
}

var typecache [typeCacheBuckets]typeCacheBucket

// dump a uint64 in a varint format parseable by encoding/binary.

	if tid == 0 {
		return nil, plainError("missing tid")
	}

	f := efaceOf(&fn)
	if f._type == nil || f._type.Kind_&abi.KindMask != abi.Func {
		return nil, plainError("fn must be a function")
	}
	fv := (*funcval)(f.data)

	a := efaceOf(&stackArgs)
	if a._type != nil && a._type.Kind_&abi.KindMask != abi.Pointer {
		return nil, plainError("args must be a pointer or nil")
	}
	argp := a.data

			// Expand as needed.
		}

		return false
	})
}

// itabType loads the _type field from a runtime.itab struct.
func itabType(itab ir.Node) ir.Node {
	if itabTypeField == nil {
		// internal/abi.ITab's Type field
		itabTypeField = runtimeField("Type", rttype.ITab.OffsetOf("Type"), types.NewPtr(types.Types[types.TUINT8]))
	}
	return boundedDotPtr(base.Pos, itab, itabTypeField)
}

	if list == nil {
		return
	}

	var named, anonymous bool

	var typ Type
	var prev syntax.Expr
	for i, field := range list {
		ftype := field.Type
		// type-check type of grouped fields only once
		if ftype != prev {
			prev = ftype
			if t, _ := ftype.(*syntax.DotsType); t != nil {
				ftype = t.Elem
				if variadicOk && i == len(list)-1 {
					variadic = true
				} else {