traceEvStacks     // start of a section of the stack table [...traceEvStack]
	traceEvStack      // stack table entry [ID, ...{PC, func string ID, file string ID, line #}]
	traceEvStrings    // start of a section of the string dictionary [...traceEvString]
	traceEvString     // string dictionary entry [ID, length, string]
	traceEvCPUSamples // start of a section of CPU samples [...traceEvCPUSample]

	case trace.EventBad:
		if region.Start != nil {
			t.Errorf("expected nil region start event, got\n%s", region.Start.String())
		}
	case trace.EventStateTransition, trace.EventRegionBegin:
		if region.Start == nil {
			t.Error("expected non-nil region start event, got nil")
		}
		kind := region.Start.Kind()
		if kind != wantStart {
			t.Errorf("wanted region start event %s, got %s", wantStart, kind)
		}

		"Total number of bucket scans finished since server start")
	scannerBucketScansStartedMD = NewCounterMD(scannerBucketScansStarted,
		"Total number of bucket scans started since server start")
	scannerDirectoriesScannedMD = NewCounterMD(scannerDirectoriesScanned,
		"Total number of directories scanned since server start")
	scannerObjectsScannedMD = NewCounterMD(scannerObjectsScanned,

		"Maximum number of active replication workers seen since server start")
	replicationMaxQueuedBytesMD = NewGaugeMD(replicationMaxQueuedBytes,
		"Maximum number of bytes queued for replication since server start")
	replicationMaxQueuedCountMD = NewGaugeMD(replicationMaxQueuedCount,
		"Maximum number of objects queued for replication since server start")
	replicationMaxDataTransferRateMD = NewGaugeMD(replicationMaxDataTransferRate,

type interval struct {
	start, end trace.Time
}

func (i interval) duration() time.Duration {
	return i.end.Sub(i.start)
}

func (i1 interval) overlap(i2 interval) time.Duration {
	// Assume start1 <= end1 and start2 <= end2
	if i1.end < i2.start || i2.end < i1.start {
		return 0
	}
	if i1.start < i2.start { // choose the later one
		i1.start = i2.start
	}

	EvGCStart           = 7  // GC start [timestamp, seq, stack id]
	EvGCDone            = 8  // GC done [timestamp]
	EvSTWStart          = 9  // GC mark termination start [timestamp, kind]
	EvSTWDone           = 10 // GC mark termination done [timestamp]
	EvGCSweepStart      = 11 // GC sweep start [timestamp, stack id]
	EvGCSweepDone       = 12 // GC sweep done [timestamp, swept, reclaimed]

        registry.add(Closeable, {
            instant.closing
            thread.blockUntil.lookupDone
        } as Closeable)

        when:
        async {
            start() {
                registry.close()
            }
            start {
                thread.blockUntil.closing
                try {
                    registry.get(Closeable)
                } finally {
                    instant.lookupDone

	// is a linux kernel, relocationSymbol is the name of the symbol
	// corresponding to the start address.
	Open(file string, start, limit, offset uint64, relocationSymbol string) (ObjFile, error)

	// Disasm disassembles the named object file, starting at
	// the start address and stopping at (before) the end address.
	Disasm(file string, start, end uint64, intelSyntax bool) ([]Inst, error)
}

	}

	return &taskFilter{name: strings.Join(name, ","), cond: conditions}, nil
}

func taskInterval(t *parsedTrace, s *trace.UserTaskSummary) interval {
	var i interval
	if s.Start != nil {
		i.start = s.Start.Time()
	} else {
		i.start = t.startTime()
	}
	if s.End != nil {
		i.end = s.End.Time()
	} else {
		i.end = t.endTime()
	}
	return i
}

// R5 length of a
// R7 length of b
// R4 points to the start of a
// R6 points to the start of b
// R13 points to the return value (-1/0/1)
TEXT cmpbody<>(SB),NOSPLIT|NOFRAME,$0
	BEQ	R4, R6, samebytes // same start of a and b

	SGTU	R5, R7, R9
	BNE	R0, R9, r2_lt_r1
	MOVV	R5, R14
	JMP	entry
r2_lt_r1:
	MOVV	R7, R14	// R14 is min(R4, R5)
entry:
	ADDV	R4, R14, R12	// R6 start of a, R14 end of a
	BEQ	R4, R12, samebytes // length is 0