for _, b := range f.Blocks {
		if reachable[b.ID] {
			f.Blocks[i] = b
			i++
		} else {
			if len(b.Values) > 0 {
				b.Fatalf("live values in unreachable block %v: %v", b, b.Values)
			}
			f.freeBlock(b)
		}
	}
	// zero remainder to help GC
	tail := f.Blocks[i:]
	for j := range tail {
		tail[j] = nil
	}
	f.Blocks = f.Blocks[:i]
}

// removeEdge removes the i'th outgoing edge from b (and

	f.Blocks = append(f.Blocks, b)
	f.invalidateCFG()
	return b
}

func (f *Func) freeBlock(b *Block) {
	if b.Func == nil {
		f.Fatalf("trying to free an already freed block")
	}
	// Clear everything but ID (which we reuse).
	id := b.ID
	*b = Block{}
	b.ID = id
	b.succstorage[0].b = f.freeBlocks
	f.freeBlocks = b
}

// NewValue0 returns a new value in the block with no arguments and zero aux values.

				}
			}
		}
		for _, c := range b.ControlValues() {
			if !valueMark[c.ID] {
				f.Fatalf("control value for %s is missing: %v", b, c)
			}
		}
	}
	for b := f.freeBlocks; b != nil; b = b.succstorage[0].b {
		if blockMark[b.ID] {
			f.Fatalf("used block b%d in free list", b.ID)
		}
	}
	for v := f.freeValues; v != nil; v = v.argstorage[0] {
		if valueMark[v.ID] {