[clang] [clang][OpenMP] Add OpenMP GPU optimization flag framework (PR #178914)

[Johannes Doerfert via cfe-commits]

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@@ -4012,6 +4016,21 @@ def fopenmp_target_new_runtime : Flag<["-"], "fopenmp-target-new-runtime">,
   Group<f_Group>, Flags<[HelpHidden]>, Visibility<[ClangOption, CC1Option]>;
 def fno_openmp_target_new_runtime : Flag<["-"], "fno-openmp-target-new-runtime">,
   Group<f_Group>, Flags<[HelpHidden]>, Visibility<[ClangOption, CC1Option]>;
+def fopenmp_target_ignore_env_vars : Flag<["-"], "fopenmp-target-ignore-env-vars">,
+  Group<f_Group>, Flags<[NoArgumentUnused, HelpHidden]>,
+  Visibility<[ClangOption, CC1Option]>,
+  HelpText<"Assume that the OpenMP runtime can ignore environment variables during code generation for GPU offload">,
+  MarshallingInfoFlag<LangOpts<"OpenMPTargetIgnoreEnvVars">>;
+def fno_openmp_target_ignore_env_vars : Flag<["-"], "fno-openmp-target-ignore-env-vars">,
+  Group<f_Group>, Flags<[NoArgumentUnused, HelpHidden]>,
+  Visibility<[ClangOption, CC1Option]>;
+def fopenmp_target_fast : Flag<["-"], "fopenmp-target-fast">,
+  Group<f_Group>, Flags<[NoArgumentUnused, HelpHidden]>,
+  Visibility<[ClangOption, CC1Option]>,
+  HelpText<"Convenience flag to enable aggressive OpenMP GPU optimizations">;
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jdoerfert wrote:

It's more than aggressive optimizations. It's "common" assumptions, right? That is a huge difference and should be noted.

https://github.com/llvm/llvm-project/pull/178914