[llvm] [KnownFPClass] Refine known classes for `KnownFPClass::bitcast` (PR #215708)

[via llvm-commits]

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+//===- KnownFPClassTest.cpp - KnownFPClass tests --------------------------===//
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ZERICO2005 wrote:

I converted the cases that can be expressed through LLVM IR to `lit` tests.

The remaining unit tests (`BitcastExhaustiveIEEEHalf`, `BitcastConstant`, and `BitcastConflict`) directly exercise `KnownFPClass::bitcast`. They do not use `ValueTracking` or LLVM IR parsing, so I do not think they belong in `unittests/Analysis/ValueTrackingTest.cpp`.

Since `KnownFPClass` is implemented in `Support`, I placed these tests in `unittests/Support/KnownFPClassTest.cpp`. Would you prefer a different location?


https://github.com/llvm/llvm-project/pull/215708