Debug in-loop tentative loads to the point that a simple test passes.

Next up: exit-to-failed-path from inside a commits-out-of-line (vararg/shared) function.
Extend failures-inside-functions to cover functions committed out-of-line (i.e. vararg functions and shared functions).

The method is to return a flag or augmented structure-with-flag and case on that at the callsite.

As part of this, switch to always reconstructing calls rather than cloning and setting operands, as setCalledFunction with a differing return type doesn't work properly.