[llvm] [Analysis][NFC] Extract KnownFPClass (PR #133457)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `lldb-aarch64-windows` running on `linaro-armv8-windows-msvc-05` while building `llvm` at step 6 "test".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/141/builds/7431

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 6 (test) failure: build (failure)
...
PASS: lldb-api :: python_api/format/TestFormat.py (1053 of 2104)
PASS: lldb-api :: python_api/formatters/TestFormattersSBAPI.py (1054 of 2104)
PASS: lldb-api :: python_api/frame/TestFrames.py (1055 of 2104)
PASS: lldb-api :: python_api/frame/get-variables/TestGetVariables.py (1056 of 2104)
PASS: lldb-api :: python_api/frame/inlines/TestInlinedFrame.py (1057 of 2104)
UNSUPPORTED: lldb-api :: python_api/function_symbol/TestDisasmAPI.py (1058 of 2104)
UNSUPPORTED: lldb-api :: python_api/function_symbol/TestSymbolAPI.py (1059 of 2104)
PASS: lldb-api :: python_api/get-value-32bit-int/TestGetValue32BitInt.py (1060 of 2104)
UNSUPPORTED: lldb-api :: python_api/global_module_cache/TestGlobalModuleCache.py (1061 of 2104)
TIMEOUT: lldb-api :: functionalities/step-vrs-interrupt/TestStepVrsInterruptTimeout.py (1062 of 2104)
******************** TEST 'lldb-api :: functionalities/step-vrs-interrupt/TestStepVrsInterruptTimeout.py' FAILED ********************
Script:
--
C:/Users/tcwg/scoop/apps/python/current/python.exe C:/Users/tcwg/llvm-worker/lldb-aarch64-windows/llvm-project/lldb\test\API\dotest.py -u CXXFLAGS -u CFLAGS --env LLVM_LIBS_DIR=C:/Users/tcwg/llvm-worker/lldb-aarch64-windows/build/./lib --env LLVM_INCLUDE_DIR=C:/Users/tcwg/llvm-worker/lldb-aarch64-windows/build/include --env LLVM_TOOLS_DIR=C:/Users/tcwg/llvm-worker/lldb-aarch64-windows/build/./bin --arch aarch64 --build-dir C:/Users/tcwg/llvm-worker/lldb-aarch64-windows/build/lldb-test-build.noindex --lldb-module-cache-dir C:/Users/tcwg/llvm-worker/lldb-aarch64-windows/build/lldb-test-build.noindex/module-cache-lldb\lldb-api --clang-module-cache-dir C:/Users/tcwg/llvm-worker/lldb-aarch64-windows/build/lldb-test-build.noindex/module-cache-clang\lldb-api --executable C:/Users/tcwg/llvm-worker/lldb-aarch64-windows/build/./bin/lldb.exe --compiler C:/Users/tcwg/llvm-worker/lldb-aarch64-windows/build/./bin/clang.exe --dsymutil C:/Users/tcwg/llvm-worker/lldb-aarch64-windows/build/./bin/dsymutil.exe --make C:/Users/tcwg/scoop/shims/make.exe --llvm-tools-dir C:/Users/tcwg/llvm-worker/lldb-aarch64-windows/build/./bin --lldb-obj-root C:/Users/tcwg/llvm-worker/lldb-aarch64-windows/build/tools/lldb --lldb-libs-dir C:/Users/tcwg/llvm-worker/lldb-aarch64-windows/build/./lib --skip-category=watchpoint C:\Users\tcwg\llvm-worker\lldb-aarch64-windows\llvm-project\lldb\test\API\functionalities\step-vrs-interrupt -p TestStepVrsInterruptTimeout.py
--
Exit Code: 15
Timeout: Reached timeout of 600 seconds

Command Output (stdout):
--
lldb version 21.0.0git (https://github.com/llvm/llvm-project.git revision 049f179606a4af3ea650d7049626d267e01b79e2)
  clang revision 049f179606a4af3ea650d7049626d267e01b79e2
  llvm revision 049f179606a4af3ea650d7049626d267e01b79e2

--

********************
PASS: lldb-api :: python_api/interpreter/TestCommandInterpreterAPI.py (1063 of 2104)
PASS: lldb-api :: python_api/hello_world/TestHelloWorld.py (1064 of 2104)
PASS: lldb-api :: python_api/interpreter/TestCommandOverrideCallback.py (1065 of 2104)
PASS: lldb-api :: python_api/interpreter/TestRunCommandInterpreterAPI.py (1066 of 2104)
PASS: lldb-api :: python_api/lldbutil/TestSwigVersion.py (1067 of 2104)
PASS: lldb-api :: python_api/interpreter_callback/TestCommandInterepterPrintCallback.py (1068 of 2104)
PASS: lldb-api :: python_api/lldbutil/frame/TestFrameUtils.py (1069 of 2104)
PASS: lldb-api :: python_api/lldbutil/iter/TestRegistersIterator.py (1070 of 2104)
PASS: lldb-api :: python_api/lldbutil/iter/TestLLDBIterator.py (1071 of 2104)
PASS: lldb-api :: python_api/lldbutil/process/TestPrintStackTraces.py (1072 of 2104)
PASS: lldb-api :: python_api/module_spec/TestModuleSpec.py (1073 of 2104)
UNSUPPORTED: lldb-api :: python_api/name_lookup/TestNameLookup.py (1074 of 2104)
UNSUPPORTED: lldb-api :: python_api/objc_type/TestObjCType.py (1075 of 2104)
PASS: lldb-api :: python_api/module_section/TestModuleAndSection.py (1076 of 2104)
PASS: lldb-api :: python_api/process/address-masks/TestAddressMasks.py (1077 of 2104)
PASS: lldb-api :: python_api/process/cancel_attach/TestCancelAttach.py (1078 of 2104)
UNSUPPORTED: lldb-api :: python_api/process/io/TestProcessIO.py (1079 of 2104)
PASS: lldb-api :: python_api/process/TestProcessAPI.py (1080 of 2104)
PASS: lldb-api :: python_api/process/read-mem-cstring/TestReadMemCString.py (1081 of 2104)
XFAIL: lldb-api :: python_api/run_locker/TestRunLocker.py (1082 of 2104)
PASS: lldb-api :: python_api/sbdata/TestSBData.py (1083 of 2104)
PASS: lldb-api :: python_api/sbenvironment/TestSBEnvironment.py (1084 of 2104)

```

</details>

https://github.com/llvm/llvm-project/pull/133457