[flang] [clang] [flang]Add support for -moutline-atomics and -mno-outline-atomics (PR #78755)

[Andrzej Warzyński via cfe-commits]

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@@ -354,6 +354,27 @@ void Flang::addTargetOptions(const ArgList &Args,
     CmdArgs.push_back(Args.MakeArgString(CPU));
   }
 
+  if (Arg *A = Args.getLastArg(options::OPT_moutline_atomics,
+                               options::OPT_mno_outline_atomics)) {
+    // Option -moutline-atomics supported for AArch64 target only.
+    if (!Triple.isAArch64()) {
+      D.Diag(diag::warn_drv_moutline_atomics_unsupported_opt)
+          << Triple.getArchName() << A->getOption().getName();
+    } else {
+      if (A->getOption().matches(options::OPT_moutline_atomics)) {
+        CmdArgs.push_back("-target-feature");
+        CmdArgs.push_back("+outline-atomics");
+      } else {
+        CmdArgs.push_back("-target-feature");
+        CmdArgs.push_back("-outline-atomics");
+      }
+    }
+  } else if (Triple.isAArch64() &&
+             getToolChain().IsAArch64OutlineAtomicsDefault(Args)) {
+    CmdArgs.push_back("-target-feature");
+    CmdArgs.push_back("+outline-atomics");
+  }
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banach-space wrote:

That's usually done in places like https://github.com/llvm/llvm-project/blob/main/clang/lib/Driver/ToolChains/CommonArgs.cpp

https://github.com/llvm/llvm-project/pull/78755