// GC checkmarks
//
// In a concurrent garbage collector, one worries about failing to mark
// a live object due to mutations without write barriers or bugs in the
// collector implementation. As a sanity check, the GC has a 'checkmark'
// mode that retraverses the object graph with the world stopped, to make
// sure that everything that should be marked is marked.

package runtime

import (
	"internal/goarch"
	"internal/runtime/atomic"

	ptrs := pp.wbBuf.buf[:n]

	// Poison the buffer to make extra sure nothing is enqueued
	// while we're processing the buffer.
	pp.wbBuf.next = 0

	if useCheckmark {
		// Slow path for checkmark mode.
		for _, ptr := range ptrs {
			shade(ptr)
		}
		pp.wbBuf.reset()
		return
	}

	// Mark all of the pointers in the buffer and record only the