// transition.
			beforeState = ProcIdle
		}
		s = procStateTransition(ProcID(e.base.args[0]), beforeState, ProcIdle)
	case go122.EvProcStatus:
		// N.B. ordering.advance populates e.base.extra.
		s = procStateTransition(ProcID(e.base.args[0]), ProcState(e.base.extra(version.Go122)[0]), go122ProcStatus2ProcState[e.base.args[1]])
	case go122.EvGoCreate, go122.EvGoCreateBlocked:

type resource interface {
	trace.GoID | trace.ProcID | trace.ThreadID
}

// noResource indicates the lack of a resource.
const noResource = -1

// gState represents the trace viewer state of a goroutine in a trace.
//
// The type parameter on this type is the resource which is used to construct
// a timeline of events. e.g. R=ProcID for a proc-oriented view, R=GoID for
// a goroutine-oriented view, etc.

		hi := g0.stack.hi
		lo := g0.stack.lo
		g0.stack.hi = sp + 1024
		g0.stack.lo = sp - 32*1024
		g0.stackguard0 = g0.stack.lo + stackGuard
		g0.stackguard1 = g0.stackguard0

		print("M ", mp.id, " procid ", mp.procid, " runtime: cgocallback with sp=", hex(sp), " out of bounds [", hex(lo), ", ", hex(hi), "]")
		print("\n")
		exit(2)
	}

	if !mp.isextra {
		// We allocated the stack for standard Ms. Don't replace the

		if err != nil {
			return nil, err
		}
		mid := ThreadID(m)

		// Read the sample's P.
		p, err := binary.ReadUvarint(r)
		if err != nil {
			return nil, err
		}
		pid := ProcID(p)

		// Read the sample's G.
		g, err := binary.ReadUvarint(r)
		if err != nil {
			return nil, err
		}
		goid := GoID(g)
		if g == 0 {
			goid = NoGoroutine
		}

	// In parent, return.
	BEQ	R2, 3(PC)
	MOVW	R2, ret+40(FP)
	RET

	// In child, on new stack.
	MOVV	-32(R29), R16
	MOVV	$1234, R1
	BEQ	R16, R1, 2(PC)
	MOVV	R0, 0(R0)

	// Initialize m->procid to Linux tid
	MOVV	$SYS_gettid, R2
	SYSCALL

	MOVV	-24(R29), R18		// fn
	MOVV	-16(R29), R17		// g
	MOVV	-8(R29), R16		// m

	BEQ	R16, nog
	BEQ	R17, nog

	MOVV	R2, m_procid(R16)

	# saved scheduler state. Find G's OS thread.
	m = ptr['m']
	if m == 0:
		return None, None
	for thr in gdb.selected_inferior().threads():
		if thr.ptid[1] == m['procid']:
			break
	else:
		return None, None
	# Get scheduler state from the G's OS thread state.
	curthr = gdb.selected_thread()
	try:
		thr.switch()
		pc = gdb.parse_and_eval('$pc')

	BEQ	ZERO, A0, child
	MOVW	ZERO, ret+40(FP)
	RET

child:
	// In child, on new stack.
	MOV	-32(X2), T0
	MOV	$1234, A0
	BEQ	A0, T0, good
	WORD	$0	// crash

good:
	// Initialize m->procid to Linux tid
	MOV	$SYS_gettid, A7
	ECALL

	MOV	-24(X2), T2	// fn
	MOV	-16(X2), T1	// g
	MOV	-8(X2), T0	// m

	BEQ	ZERO, T0, nog
	BEQ	ZERO, T1, nog

	MOV	A0, m_procid(T0)

	MOVW	R2, ret+40(FP)
	RET

	// In child, on new stack.
	// initialize essential registers
	XOR	R0, R0
	MOVD	-32(R15), R7
	CMP	R7, $1234
	BEQ	2(PC)
	MOVD	R0, 0(R0)

	// Initialize m->procid to Linux tid
	SYSCALL $SYS_gettid

	MOVD	-24(R15), R9        // fn
	MOVD	-16(R15), R8        // g
	MOVD	-8(R15), R7         // m

	CMPBEQ	R7, $0, nog
	CMP	R8, $0
	BEQ	nog

		print("runtime.minit: duplicatehandle failed; errno=", getlasterror(), "\n")
		throw("runtime.minit: duplicatehandle failed")
	}

	mp := getg().m
	lock(&mp.threadLock)
	mp.thread = thandle
	mp.procid = uint64(stdcall0(_GetCurrentThreadId))

	// Configure usleep timer, if possible.
	if mp.highResTimer == 0 && haveHighResTimer {
		mp.highResTimer = createHighResTimer()
		if mp.highResTimer == 0 {

	// In parent, return.
	BEQ	R4, 3(PC)
	MOVW	R4, ret+40(FP)
	RET

	// In child, on new stack.
	MOVV	-32(R3), R23
	MOVV	$1234, R19
	BEQ	R23, R19, 2(PC)
	MOVV	R0, 0(R0)

	// Initialize m->procid to Linux tid
	MOVV	$SYS_gettid, R11
	SYSCALL

	MOVV	-24(R3), R25		// fn
	MOVV	-16(R3), R24		// g
	MOVV	-8(R3), R23		// m

	BEQ	R23, nog
	BEQ	R24, nog

	MOVV	R4, m_procid(R23)