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

[Mikołaj Piróg 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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mikolaj-pirog wrote:

There aren't any specific differences between x86 and aarch64 in this change; I am testing both just in case. I see that this potentially limits the set of configuration of testing, but already many COFF tests limit themselves to x86/aarch64, as these are the only platform modern Windows supports

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