[clang] [flang] [llvm] Add IR Profile-Guided Optimization (IR PGO) support to the Flang compiler (PR #136098)

[Tarun Prabhu via cfe-commits]

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@@ -20,8 +20,13 @@
 #include "mlir/IR/OwningOpRef.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/IR/Module.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/PGOOptions.h"
 #include <memory>
 
+namespace llvm {
+extern cl::opt<llvm::PGOOptions::ColdFuncOpt> ClPGOColdFuncAttr;
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tarunprabhu wrote:

We probably don't want to expose this here. It is an experimental option that may be promoted to a proper frontend option at some point. It is better to leave this as a declaration in the .cpp file where this is actually used.

https://github.com/llvm/llvm-project/pull/136098