defer func() { f.Cache.freeValueSlice(order) }()

	// Remove dead & duplicate entries from namedValues map.
	s := f.newSparseSet(f.NumValues())
	defer f.retSparseSet(s)
	i := 0
	for _, name := range f.Names {
		j := 0
		s.clear()
		values := f.NamedValues[*name]
		for _, v := range values {
			if live[v.ID] && !s.contains(v.ID) {
				values[j] = v
				j++
				s.add(v.ID)

		for i, v := range b.ControlValues() {
			if v.Op == OpCopy {
				b.ReplaceControl(i, v.Args[0])
			}
		}
	}

	// Update named values.
	for _, name := range f.Names {
		values := f.NamedValues[*name]
		for i, v := range values {
			if v.Op == OpCopy {
				values[i] = v.Args[0]
			}
		}
	}
}

// copySource returns the (non-copy) op which is the
// ultimate source of v.  v must be a copy op.

					p.value(v, live[v.ID])
					printed[v.ID] = true
					n++
				}
				p.endDepCycle()
			}
		}

		p.endBlock(b, reachable[b.ID])
	}
	for _, name := range f.Names {
		p.named(*name, f.NamedValues[*name])
	}