[llvm] [InstCombine] Fold more 'fcmp' 'select' instrs idioms into 'fabs' (PR #83381)

[Nikita Popov via llvm-commits]

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nikic wrote:

Adding this kind of test is fine if it tests the whole pipeline (e.g. `-O2`) and is in the PhaseOrdering directory. But if @jcranmer-intel thinks we don't need this, then it's fine.

https://github.com/llvm/llvm-project/pull/83381