func MakeSlice[T any](a *Arena, len, cap int) []T {
	var sl []T
	runtime_arena_arena_Slice(a.a, &sl, cap)
	return sl[:len]
}

// Clone makes a shallow copy of the input value that is no longer bound to any
// arena it may have been allocated from, returning the copy. If it was not
// allocated from an arena, it is returned untouched. This function is useful
// to more easily let an arena-allocated value out-live its arena.

	case *ast.ReturnStmt:
		f.walk(n.Results, ctxExpr, visit)
	case *ast.BranchStmt:
	case *ast.BlockStmt:
		f.walk(n.List, context, visit)
	case *ast.IfStmt:
		f.walk(n.Init, ctxStmt, visit)
		f.walk(&n.Cond, ctxExpr, visit)
		f.walk(n.Body, ctxStmt, visit)
		f.walk(n.Else, ctxStmt, visit)
	case *ast.CaseClause:
		if context == ctxTypeSwitch {
			context = ctxType
		} else {
			context = ctxExpr
		}

<p>
Slice expressions construct a substring or slice from a string, array, pointer
to array, or slice. There are two variants: a simple form that specifies a low
and high bound, and a full form that also specifies a bound on the capacity.
</p>

<h4>Simple slice expressions</h4>

<p>
For a string, array, pointer to array, or slice <code>a</code>, the primary expression
</p>

<pre>

pkg syscall (netbsd-arm64-cgo), const SYS_ADJTIME = 421
pkg syscall (netbsd-arm64-cgo), const SYS_ADJTIME ideal-int
pkg syscall (netbsd-arm64-cgo), const SYS_BIND = 104
pkg syscall (netbsd-arm64-cgo), const SYS_BIND ideal-int
pkg syscall (netbsd-arm64-cgo), const SYS_BREAK = 17
pkg syscall (netbsd-arm64-cgo), const SYS_BREAK ideal-int
pkg syscall (netbsd-arm64-cgo), const SYS_CHDIR = 12

// codes, such as ".P.W". An initial period is ignored.
func ParseARMCondition(cond string) (uint8, bool) {
	return parseARMCondition(cond, armLS, armSCOND)
}

func parseARMCondition(cond string, ls, scond map[string]uint8) (uint8, bool) {
	cond = strings.TrimPrefix(cond, ".")
	if cond == "" {
		return arm.C_SCOND_NONE, true
	}
	names := strings.Split(cond, ".")
	bits := uint8(0)
	for _, name := range names {

//	}
//	LTYPE1 cond imsr ',' reg
//	{
//		outcode($1, $2, &$3, 0, &$5);
//	}
	ADD	$1, R2
	ADD	R1<<R2, R3
	ADD	R1>>R2, R3
	ADD	R1@>R2, R3
	ADD	R1->R2, R3
	ADD	R1, R2

//
// MVN
//
//	LTYPE2 cond imsr ',' reg
//	{
//		outcode($1, $2, &$3, 0, &$5);
//	}
	CLZ	R1, R2

//
// MOVW
//
//	LTYPE3 cond gen ',' gen
//	{
//		outcode($1, $2, &$3, 0, &$5);
//	}

pkg syscall (darwin-arm64), const IPV6_BINDV6ONLY = 27
pkg syscall (darwin-arm64), const IPV6_BINDV6ONLY ideal-int
pkg syscall (darwin-arm64), const IPV6_BOUND_IF = 125
pkg syscall (darwin-arm64), const IPV6_BOUND_IF ideal-int
pkg syscall (darwin-arm64), const IPV6_CHECKSUM = 26
pkg syscall (darwin-arm64), const IPV6_CHECKSUM ideal-int
pkg syscall (darwin-arm64), const IPV6_DEFAULT_MULTICAST_HOPS = 1

pkg strings, method (*Replacer) WriteString(io.Writer, string) (int, error)
pkg strings, type Reader struct
pkg strings, type Replacer struct
pkg sync, func NewCond(Locker) *Cond
pkg sync, method (*Cond) Broadcast()
pkg sync, method (*Cond) Signal()
pkg sync, method (*Cond) Wait()
pkg sync, method (*Mutex) Lock()
pkg sync, method (*Mutex) Unlock()
pkg sync, method (*Once) Do(func())
pkg sync, method (*RWMutex) Lock()

	CASPD	(R30, ZR), (RSP), (R8, R9)           // e87f3e48
	CASPW	(R6, R7), (R8), (R4, R5)             // 047d2608
	CASPD	(R2, R3), (R2), (R8, R9)             // 487c2248

// RET
	RET
	RET	foo(SB)

// B/BL/B.cond cases, and canonical names JMP, CALL.
	BL	1(PC)      // CALL 1(PC)
	BL	(R2)       // CALL (R2)
	BL	foo(SB)    // CALL foo(SB)
	BL	bar<>(SB)  // CALL bar<>(SB)
	B	foo(SB)    // JMP foo(SB)
	BEQ	1(PC)
	BEQ	2(PC)

pkg syscall (freebsd-arm64), const SYS_AUDITON = 446
pkg syscall (freebsd-arm64), const SYS_AUDITON ideal-int
pkg syscall (freebsd-arm64), const SYS_BIND = 104
pkg syscall (freebsd-arm64), const SYS_BIND ideal-int
pkg syscall (freebsd-arm64), const SYS_BINDAT = 538
pkg syscall (freebsd-arm64), const SYS_BINDAT ideal-int
pkg syscall (freebsd-arm64), const SYS_CAP_ENTER = 516