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

[Reid Kleckner via cfe-commits]

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@@ -112,6 +112,8 @@ class MCTargetOptions {
   // Whether or not to use full register names on PowerPC.
   bool PPCUseFullRegisterNames : 1;
 
+  bool PgoInstrumentation = false;
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rnk wrote:

Target options like this don't play well with (thin)LTO , because they don't carry over naturally from the frontend compilation step to the backend compilation step, which LTO separates. Is there an existing global named metadata flag you can look for instead to control this debug info setting?

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