Conditionally simplify use of if-then-else conditions

[tautschnig]

When symbolically executing (and dereferencing) statements like *p = *p + 1; where p may point to more than a single object we ended up with nested if-then-else expressions on the right-hand side that would use the very same conditions. In this particular case, we should propagate the conditions into nested if-then-else expressions. This simplification may be expensive, so we don't enable it in general.

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 78.38%. Comparing base (1ed7b2f) to head (830a7f1).

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #8042   +/-   ##
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  Coverage    78.38%   78.38%           
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  Files         1720     1720           
  Lines       187982   188010   +28     
  Branches     18474    18477    +3     
========================================
+ Hits        147346   147376   +30     
+ Misses       40636    40634    -2     

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