Correct the stack-pruning optimization.
Correct the stack-pruning optimization.

The load-back-saved-registers at function epilogues were never optimized
away because of a faulty check. This fixes that.


SimonKagstrom/cibyl,SimonKagstrom/cibyl,SimonKagstrom/cibyl,SimonKagstrom/cibyl,SimonKagstrom/cibyl