[clang] [compiler-rt] [ubsan] Limit _BitInt ubsan tests to x86-64 platform only (PR #104494)

[via llvm-commits]

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@@ -1,3 +1,4 @@
+// REQUIRES: x86_64-target-arch
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zmodem wrote:

It seems the test does pass when there are 128-bit runtime routines available on Windows, which means the XFAIL breaks: https://logs.chromium.org/logs/chromium/buildbucket/cr-buildbucket/8739197731419270081/+/u/package_clang/stdout

I'll add `REQUIRES: !windows` for now instead.

https://github.com/llvm/llvm-project/pull/104494