[clang] [lld] [llvm] [Windows] Add support for emitting PGO/LTO magic strings in the Windows PE debug directory (PR #114260)

[Martin Storsjö via cfe-commits]

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@@ -0,0 +1,26 @@
+// This test checks if COFF file compiled with
+// -fprofile-generate has magic section ".pgi" to indicate so.
+
+// RUN: %clang --target=x86_64-pc-windows -fprofile-generate %s -c -o %t_x86
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mstorsjo wrote:

Yes - I'm not saying that this should be tested on more platforms - on the contrary.

My point was, consider if we'd have two buildbots, one which only has enabled the x86 target, and another one that only has enabled the aarch64 target - then neither of these will run any of the tests, as they require _both_ x86 and aarch64 to be enabled at the same time. We certainly have lots of build configurations with both targets enabled at the same time though, so it's not a big practical issue though. But if adding the other architecture doesn't add any relevant test coverage, I would just pick one of them (x86 is probably the most often enabled target) and stick with that.

https://github.com/llvm/llvm-project/pull/114260