// 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 {

	}
}

// Keep this code in sync with cmd/compile/internal/walk/builtin.go:walkUnsafeSlice
func unsafeslice64(et *_type, ptr unsafe.Pointer, len64 int64) {
	len := int(len64)
	if int64(len) != len64 {
		panicunsafeslicelen1(getcallerpc())
	}
	unsafeslice(et, ptr, len)
}

func unsafeslicecheckptr(et *_type, ptr unsafe.Pointer, len64 int64) {
	unsafeslice64(et, ptr, len64)

	parent_tid *int32
	flags      int32
	rtp        *rtprio
	spare      [3]uintptr
}

type thread int32 // long

type sigset struct {
	__bits [4]uint32
}

type stackt struct {
	ss_sp    uintptr
	ss_size  uintptr
	ss_flags int32
}

type siginfo struct {
	si_signo  int32
	si_errno  int32
	si_code   int32
	si_pid    int32
	si_uid    uint32
	si_status int32

	St_res05        [16]uint8 // 0xc8
	// end of version 2
}

type BpxFilestatus struct {
	Oflag1 byte
	Oflag2 byte
	Oflag3 byte
	Oflag4 byte
}

type BpxMode struct {
	Ftype byte
	Mode1 byte
	Mode2 byte
	Mode3 byte
}

// Thr attribute structure for extended attributes
type Bpxyatt_t struct { // DSECT BPXYATT
	Att_id           [4]uint8
	Att_version      uint16

	flags      int32
	pad_cgo_0  [4]byte
	rtp        *rtprio
	spare      [3]uintptr
}

type thread int64 // long

type sigset struct {
	__bits [4]uint32
}

type stackt struct {
	ss_sp     uintptr
	ss_size   uintptr
	ss_flags  int32
	pad_cgo_0 [4]byte
}

type siginfo struct {
	si_signo  int32
	si_errno  int32
	si_code   int32
	si_pid    int32
	si_uid    uint32

type Error interface {
	error

	// RuntimeError is a no-op function but
	// serves to distinguish types that are run time
	// errors from ordinary errors: a type is a
	// run time error if it has a RuntimeError method.
	RuntimeError()
}

// A TypeAssertionError explains a failed type assertion.
type TypeAssertionError struct {
	_interface    *_type
	concrete      *_type

// wbMove performs the write barrier operations necessary before
// copying a region of memory from src to dst of type typ.
// Does not actually do the copying.
//
//go:nowritebarrierrec
//go:nosplit
func wbMove(typ *_type, dst, src unsafe.Pointer) {
	// This always copies a full value of type typ so it's safe to
	// pass a type here.
	//
	// See the comment on bulkBarrierPreWrite.