// This must be called with preemption enabled.
func gcAssistAlloc(gp *g) {
	// Don't assist in non-preemptible contexts. These are
	// generally fragile and won't allow the assist to block.
	if getg() == gp.m.g0 {
		return
	}
	if mp := getg().m; mp.locks > 0 || mp.preemptoff != "" {
		return
	}

	// This extremely verbose boolean indicates whether we've
	// entered mark assist from the perspective of the tracer.
	//

			// mark using checkmark bits, to check that we
			// didn't forget to mark anything during the
			// concurrent mark process.
			startCheckmarks()
			gcResetMarkState()
			gcw := &getg().m.p.ptr().gcw
			gcDrain(gcw, 0)
			wbBufFlush1(getg().m.p.ptr())
			gcw.dispose()
			endCheckmarks()
		}

		// marking is complete so we can turn the write barrier off
		setGCPhase(_GCoff)
		stwSwept = gcSweep(work.mode)

	var stw worldStop
	if all {
		stw = stopTheWorld(stwAllGoroutinesStack)
	}

	n := 0
	if len(buf) > 0 {
		gp := getg()
		sp := getcallersp()
		pc := getcallerpc()
		systemstack(func() {
			g0 := getg()
			// Force traceback=1 to override GOTRACEBACK setting,
			// so that Stack's results are consistent.
			// GOTRACEBACK is only about crash dumps.

	}
	call(cgoSymbolizer, noescape(unsafe.Pointer(arg)))
}

// cgoContextPCs gets the PC values from a cgo traceback.
func cgoContextPCs(ctxt uintptr, buf []uintptr) {
	if cgoTraceback == nil {
		return
	}
	call := cgocall
	if panicking.Load() > 0 || getg().m.curg != getg() {
		// We do not want to call into the scheduler when panicking
		// or when on the system stack.

		// Make sure we keep ep alive. We may have stopped referencing
		// ep's data pointer sometime before this point and it's possible
		// for that memory to get freed.
		KeepAlive(ep)
		return
	}

	// stack
	if gp := getg(); gp.m.curg.stack.lo <= uintptr(p) && uintptr(p) < gp.m.curg.stack.hi {
		found := false
		var u unwinder

				} else if size&1 == 0 {
					align = 2
				} else {
					align = 1
				}
			}
			return persistentalloc(size, align, &memstats.other_sys)
		}

		if inittrace.active && inittrace.id == getg().goid {
			// Init functions are executed sequentially in a single goroutine.
			inittrace.allocs += 1
		}
	}

	// assistG is the G to charge for this allocation, or nil if

	lock(&s.lock)
	if getg() != s.g {
		throw("tried to sleep scavenger from another goroutine")
	}

	if worked < minScavWorkTime {
		// This means there wasn't enough work to actually fill up minScavWorkTime.
		// That's fine; we shouldn't try to do anything with this information
		// because it's going result in a short enough sleep request that things
		// will get messy. Just assume we did at least this much work.

type mSpanStateBox struct {
	s atomic.Uint8
}

// It is nosplit to match get, below.

//go:nosplit
func (b *mSpanStateBox) set(s mSpanState) {
	b.s.Store(uint8(s))
}

// It is nosplit because it's called indirectly by typedmemclr,
// which must not be preempted.

//go:nosplit
func (b *mSpanStateBox) get() mSpanState {
	return mSpanState(b.s.Load())
}

	CmdGet.Run = runGet // break init loop
	CmdGet.Flag.Var(&getD, "d", "")
	CmdGet.Flag.Var(&getU, "u", "")
}

func runGet(ctx context.Context, cmd *base.Command, args []string) {
	switch getU.version {
	case "", "upgrade", "patch":
		// ok
	default:
		base.Fatalf("go: unknown upgrade flag -u=%s", getU.rawVersion)
	}
	if getD.set {
		if !getD.value {
			base.Fatalf("go: -d flag may not be set to false")
		}

			c.setMaxIdleMarkWorkers(0)
		} else {
			// TODO(mknyszek): The fundamental reason why we need this is because
			// we can't count on the fractional mark worker to get scheduled.
			// Fix that by ensuring it gets scheduled according to its quota even
			// if the rest of the application is idle.
			c.setMaxIdleMarkWorkers(1)
		}
	} else {