SMT2: typecasts to the source type

[kroening]

This adds support for typecast expressions that cast to the type of the operand to the SMT2 converter.

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[tautschnig]

Seems fine and should be supported for sure, but why are we running into this at all? The simplifier should have gotten rid of this, so I suppose there is code that never sees the simplifier.

[kroening]

Seems fine and should be supported for sure, but why are we running into this at all? The simplifier should have gotten rid of this, so I suppose there is code that never sees the simplifier.

Yes, we never made an effort to ensure that only simplified expressions are given to solvers.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 80.00%. Comparing base (05c2649) to head (a6997dd).
⚠️ Report is 2 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #8828   +/-   ##
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  Coverage    80.00%   80.00%           
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  Files         1700     1700           
  Lines       188332   188335    +3     
  Branches        73       73           
========================================
+ Hits        150679   150685    +6     
+ Misses       37653    37650    -3     

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[tautschnig]

Yes, we never made an effort to ensure that only simplified expressions are given to solvers.

I don't think that should be a requirement either, but it may point to a missed opportunity to use the simplifier.