builder: save a slot information within conditional warps
mutator: Swap addresses for swapped ends to keep an order
Fixup builder
locals: Use only reliable addresses

Identifier addresses may come from a further code, thanks to the
elimination process
unwarper: Improve the expression/statement analysis by using the slot information
unwarper: Fix few comment typos
unwaper: An unconditional warp could also be inverted
test: Add more testcases from X:R files