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

[Tobias Hieta via cfe-commits]

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@@ -0,0 +1,13 @@
+// This test checks if Window PE file compiled with -flto option contains a magic 
+// string "LTCG" to indicate LTO compilation.
+
+// REQUIRES: system-windows
+
+// RUN: %clang --target=x86_64-pc-windows-msvc -flto -fuse-ld=lld %s -o %t.exe
+// RUN: dumpbin /HEADERS %t.exe | FileCheck %s
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tru wrote:

I don't think I am sure it's correct to rely on dumpbin here. I think we have other tools in LLVM that can extract this info and it would allow us to run this test on another OS as well. 

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