// free slots for this sweepgen.
func (c *mcentral) fullSwept(sweepgen uint32) *spanSet {
	return &c.full[sweepgen/2%2]
}

// Allocate a span to use in an mcache.
func (c *mcentral) cacheSpan() *mspan {
	// Deduct credit for this span allocation and sweep if necessary.
	spanBytes := uintptr(class_to_allocnpages[c.spanclass.sizeclass()]) * _PageSize
	deductSweepCredit(spanBytes, 0)

	traceDone := false

		// Clear the second allocCount just to be safe.
		s.allocCountBeforeCache = 0
	}

	// Get a new cached span from the central lists.
	s = mheap_.central[spc].mcentral.cacheSpan()
	if s == nil {
		throw("out of memory")
	}

	if s.allocCount == s.nelems {
		throw("span has no free space")
	}

	// Indicate that this span is cached and prevent asynchronous

//
// * The object reclaimer finds and frees unmarked slots in spans. It
//   can free a whole span if none of the objects are marked, but that
//   isn't its goal. This can be driven either synchronously by
//   mcentral.cacheSpan for mcentral spans, or asynchronously by
//   sweepone, which looks at all the mcentral lists.
//
// * The span reclaimer looks for spans that contain no marked objects

String id=183
	data="runtime.(*mcentral).grow"
String id=184
	data="/usr/local/google/home/mknyszek/work/go-1/src/runtime/mcentral.go"
String id=185
	data="runtime.(*mcentral).cacheSpan"
String id=186
	data="runtime.(*mcache).refill"
String id=187
	data="/usr/local/google/home/mknyszek/work/go-1/src/runtime/mcache.go"
String id=188
	data="runtime.(*mcache).nextFree"
String id=189

String id=53
	data="runtime.(*sweepLocked).sweep"
String id=54
	data="/usr/local/google/home/mknyszek/work/go-1/src/runtime/mgcsweep.go"
String id=55
	data="runtime.(*mcentral).cacheSpan"
String id=56
	data="/usr/local/google/home/mknyszek/work/go-1/src/runtime/mcentral.go"
String id=57
	data="runtime.(*mcache).refill"
String id=58