[llvm-bugs] [Bug 109933] [llvm-cov][MC/DC][Qualification]No MCDC coverage measured big expression

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Issue	109933
Summary	[llvm-cov][MC/DC][Qualification]No MCDC coverage measured big _expression_
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Reporter	escherle-validas

    # No MCDC coverage measured big _expression_
## Criticality: MEDIUM
During qualification of MCDC coverage at Validas we found that 
no MCDC coverage is measured when the term consists of more that 6 atoms.
In the attached example the term "(v7||(!(((v2&&TRUE)&&v3)||(!((!FALSE)||(!((!v0||v2))))))))" is not instrumented at all for MCDC.
We know that this is a known issue and that there are some warnings. Therefore it is not 
so critical, however it has to be documented in the  safety manual, even if there is a work arround.
Commercial coverage tools can measure terms with sizes up to 15.
The problem occurs within Rust and C++ (see attached reduced examples).

### Rust example
![7_atoms_rust](https://github.com/user-attachments/assets/e74c158a-78de-463e-9b55-cb77d0f400ec)

[Test_000003.zip](https://github.com/user-attachments/files/17128550/Test_000003.zip)

### C++ example:

![7_atoms_cpp](https://github.com/user-attachments/assets/3bc3b0ef-4d76-4de2-aaf7-bf5c9633a623)

[Test_000003.zip](https://github.com/user-attachments/files/17128576/Test_000003.zip)

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