Array indices reuse preventing array simplification

[emesare]

Bug Description:
It appears if the array index is reused in another block (or perhaps even the same block) that the array access is not shown (i.e. array[idx]). This is because the current array simplification occurs on a simple expression, and to get that expression (i.e. &array + idx) we must have folded in the index, a reuse of the array index would likely prevent that fold from occurring.

Expected Behavior:
There are a few solutions:

1. Loosen the folding rules when the use sites are all in a probable array access expression (i.e. check for array type), this is probably expensive.
2. In array access simplification we can follow to defsite and fold the array index in while we are doing our transformation, not exactly sure about the implications of doing this, its probably fine so long as we keep the defsite and let it get DCE'd later.

Screenshots/Video Recording:

Working:

Broken:

As you can see there is no reuse of the array index (the highlighted token) in the working sample, but there is in the broken sample.

Binary
array_simpl.zip