[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:

As this test now does compilation for both x86 and aarch64, it also requires that both those targets are enabled for this test to be runnable - so this test at least needs a matching `REQUIRES:` line. 

While it earlier was raised whether this was x86_64 specific, I wonder if it adds much value here to test both, as it (marginally) limits the set of configurations where this test is possible to run overall.

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