return nil
	}

	traceLength := len(entry.Trace.Source)
	trace := make([]string, traceLength)

	// Add a sequence number and formatting for each stack trace
	// No formatting is required for the first entry
	for i, element := range entry.Trace.Source {
		trace[i] = fmt.Sprintf("%8v: %s", traceLength-i, element)
	}

	tagString := ""
	for key, value := range entry.Trace.Variables {
		if value != "" {
			if tagString != "" {

// in a particular state for the specified reasons.
func makeComputePprofFunc(state trace.GoState, trackReason func(string) bool) computePprofFunc {
	return func(gToIntervals map[trace.GoID][]interval, events []trace.Event) ([]traceviewer.ProfileRecord, error) {
		stacks := newStackMap()
		tracking := make(map[trace.GoID]*trace.Event)
		for i := range events {
			ev := &events[i]

	b0.Event("GoSyscallEndBlocked")

	// A running goroutine stole P0 at the generation boundary.
	b1 := g.Batch(trace.ThreadID(1), 0)
	b1.Event("ProcStatus", trace.ProcID(2), go122.ProcRunning)
	b1.Event("GoStatus", trace.GoID(2), trace.ThreadID(1), go122.GoRunning)
	b1.Event("ProcStatus", trace.ProcID(0), go122.ProcSyscallAbandoned)
	b1.Event("ProcSteal", trace.ProcID(0), testgen.Seq(1), trace.ThreadID(0))

package main

import (
	"fmt"
	"internal/trace"
	"internal/trace/traceviewer"
	"internal/trace/traceviewer/format"
)

var _ generator = &procGenerator{}

type procGenerator struct {
	globalRangeGenerator
	globalMetricGenerator
	procRangeGenerator
	stackSampleGenerator[trace.ProcID]
	logEventGenerator[trace.ProcID]

	gStates   map[trace.GoID]*gState[trace.ProcID]
	inSyscall map[trace.ProcID]*gState[trace.ProcID]

		// Park the calling goroutine.
		trace := traceAcquire()
		if trace.ok() {
			// Trace the event before the transition. It may take a
			// stack trace, but we won't own the stack after the
			// transition anymore.
			trace.GoPark(traceBlockDebugCall, 1)
		}
		casGToWaiting(gp, _Grunning, waitReasonDebugCall)
		if trace.ok() {
			traceRelease(trace)
		}
		dropg()

package main

import (
	"internal/trace"
	"internal/trace/event/go122"
	testgen "internal/trace/internal/testgen/go122"
)

func main() {
	testgen.Main(gen)
}

func gen(t *testgen.Trace) {
	g := t.Generation(1)

	// One goroutine enters a syscall, grabs a P, and starts running.
	b0 := g.Batch(trace.ThreadID(0), 0)
	b0.Event("ProcStatus", trace.ProcID(1), go122.ProcIdle)

}

func describeEvent(ev *trace.Event) string {
	switch ev.Kind() {
	case trace.EventStateTransition:
		st := ev.StateTransition()
		if st.Resource.Kind != trace.ResourceGoroutine {
			return ""
		}
		old, new := st.Goroutine()
		return fmt.Sprintf("%s -> %s", old, new)
	case trace.EventRegionBegin:
		return fmt.Sprintf("region %q begin", ev.Region().Type)
	case trace.EventRegionEnd:

package main

import (
	"internal/trace"
	"internal/trace/event/go122"
	testgen "internal/trace/internal/testgen/go122"
)

func main() {
	testgen.Main(gen)
}

func gen(t *testgen.Trace) {
	g := t.Generation(1)

	// One goroutine enters a syscall.
	b0 := g.Batch(trace.ThreadID(0), 0)
	b0.Event("ProcStatus", trace.ProcID(0), go122.ProcRunning)
	b0.Event("GoStatus", trace.GoID(1), trace.ThreadID(0), go122.GoRunning)

trace, but with the `.go` extension removed.

## Trace test programs

The trace test programs in the `testprog` directory generate traces to
stdout.
Otherwise they're just normal programs.

## Trace debug commands

The `cmd` directory contains helpful tools for debugging traces.

* `gotraceraw` parses traces without validation.
  It can produce a text version of the trace wire format, or convert

	< internal/txtar;

	# v2 execution trace parser.
	FMT
	< internal/trace/event;

	internal/trace/event
	< internal/trace/event/go122;

	FMT, io, internal/trace/event/go122
	< internal/trace/version;

	FMT, encoding/binary, internal/trace/version
	< internal/trace/raw;

	FMT, internal/trace/event, internal/trace/version, io, sort, encoding/binary
	< internal/trace/internal/oldtrace;