[llvm] ConstraintSystem: replace data structure with Matrix (PR #98895)

[Florian Hahn via llvm-commits]

fhahn wrote:

Looks like Clang crashes with the dry-run version on CTmark https://llvm-compile-time-tracker.com/show_error.php?commit=94bdfca2db58d6e6ff507d073e407acba1046701

https://github.com/llvm/llvm-project/pull/98895