b0.Event("GoStatus", trace.GoID(1), trace.ThreadID(0), go122.GoSyscall)
	b0.Event("ProcStatus", trace.ProcID(1), go122.ProcIdle)
	b0.Event("ProcStart", trace.ProcID(1), testgen.Seq(1))
	b0.Event("GoSyscallEndBlocked")

	// A bare M stole the goroutine's P at the generation boundary.
	b1 := g.Batch(trace.ThreadID(1), 0)
	b1.Event("ProcStatus", trace.ProcID(0), go122.ProcSyscallAbandoned)

	b0.Event("GoSyscallBegin", testgen.Seq(1), testgen.NoStack)
	b0.Event("GoSyscallEnd")
	b0.Event("GoSyscallBegin", testgen.Seq(2), testgen.NoStack)
	b0.Event("GoSyscallEndBlocked")

	// A running goroutine steals proc 0.
	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)

	b0 := g.Batch(trace.ThreadID(0), 0)
	b0.Event("GoCreateSyscall", trace.GoID(4))
	b0.Event("ProcStatus", trace.ProcID(0), go122.ProcIdle)
	b0.Event("ProcStart", trace.ProcID(0), testgen.Seq(1))
	b0.Event("GoSyscallEndBlocked")
	b0.Event("GoStart", trace.GoID(4), testgen.Seq(1))
	b0.Event("GoSyscallBegin", testgen.Seq(2), testgen.NoStack)
	b0.Event("GoDestroySyscall")
	b0.Event("GoCreateSyscall", trace.GoID(4))
	b0.Event("GoSyscallEnd")

	g := t.Generation(1)

	// A C thread calls into Go and acquires a P. It returns
	// back to C, destroying the G.
	b0 := g.Batch(trace.ThreadID(0), 0)
	b0.Event("GoCreateSyscall", trace.GoID(4))
	b0.Event("GoSyscallEndBlocked")
	b0.Event("ProcStatus", trace.ProcID(0), go122.ProcIdle)
	b0.Event("ProcStart", trace.ProcID(0), testgen.Seq(1))
	b0.Event("GoStatus", trace.GoID(4), trace.NoThread, go122.GoRunnable)

	// it's mentioned, then there's no GoSyscallBegin to
	// connect the P stealing back to at that point. This
	// special state indicates this to the parser, so it
	// doesn't try to find a GoSyscallEndBlocked that
	// corresponds with the ProcSteal.
	traceProcSyscallAbandoned
)

// writeGoStatus emits a GoStatus event as well as any active ranges on the goroutine.