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

[Tom Eccles via cfe-commits]

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@@ -24,6 +24,11 @@ CODEGENOPT(OptimizationLevel, 2, 0) ///< The -O[0-3] option specified.
 CODEGENOPT(DebugPassManager, 1, 0) ///< Prints debug information for the new
                                    ///< pass manager.
 
+ENUM_CODEGENOPT(ProfileInstr, ProfileInstrKind, 2, ProfileNone)
+ENUM_CODEGENOPT(ProfileUse, ProfileInstrKind, 2, ProfileNone)
+/// Whether emit extra debug info for sample pgo profile collection.
+CODEGENOPT(DebugInfoForProfiling, 1, 0)
+CODEGENOPT(AtomicProfileUpdate , 1, 0) ///< Set -fprofile-update=atomic
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tblah wrote:

`-fprofile-update=atomic` is not currently supported so far as I can tell.

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