[clang] [llvm] [Clang][Lexer] Reland "Detect SSE4.2 availability at runtime in fastParseASCIIIdentifier" (PR #180631)

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github-actions[bot] wrote:

<!--PREMERGE ADVISOR COMMENT: Windows-->
# :window: Windows x64 Test Results

* 81306 tests passed
* 2005 tests skipped

All executed tests passed, but another part of the build **failed**. Click on a failure below to see the details.

<details>
<summary>[code=4294967295] bin/libclang.dll lib/libclang.lib</summary>

```
FAILED: [code=4294967295] bin/libclang.dll lib/libclang.lib
cmd.exe /C "cd . && C:\BuildTools\Common7\IDE\CommonExtensions\Microsoft\CMake\CMake\bin\cmake.exe -E vs_link_dll --intdir=tools\clang\tools\libclang\CMakeFiles\libclang.dir --rc="C:\Program Files (x86)\Windows Kits\10\bin\10.0.19041.0\x64\rc.exe" --mt="C:\Program Files (x86)\Windows Kits\10\bin\10.0.19041.0\x64\mt.exe" --manifests  -- C:\clang\clang-msvc\bin\lld-link.exe /nologo @CMakeFiles\libclang.rsp  /out:bin\libclang.dll /implib:lib\libclang.lib /pdb:bin\libclang.pdb /dll /version:23.0 /MANIFEST:NO /INCREMENTAL:NO  && cd ."
LINK: command "C:\clang\clang-msvc\bin\lld-link.exe /nologo @CMakeFiles\libclang.rsp /out:bin\libclang.dll /implib:lib\libclang.lib /pdb:bin\libclang.pdb /dll /version:23.0 /MANIFEST:NO /INCREMENTAL:NO" failed (exit code 1) with the following output:
lld-link: error: undefined symbol: LLVMInitializeWebAssemblyAsmParser
>>> referenced by tools\clang\tools\libclang\CMakeFiles\libclang.dir\CIndex.cpp.obj:(class clang::CIndexer * __cdecl clang_createIndex_Impl(int, int, unsigned char, unsigned char))
```
</details>

If these failures are unrelated to your changes (for example tests are broken or flaky at HEAD), please open an issue at https://github.com/llvm/llvm-project/issues and add the `infrastructure` label.

https://github.com/llvm/llvm-project/pull/180631