Move common code into function

Author: aschwaighofer

lib/Frontend/CompilerInvocation.cpp

@@ -1201,11 +1201,9 @@ static bool ParseIRGenArgs(IRGenOptions &Opts, ArgList &Args,
                      A->getAsString(Args), A->getValue());
     }
   }
-                             
-  // Autolink runtime compatibility libraries, if asked to.
-  if (!Args.hasArg(options::OPT_disable_autolinking_runtime_compatibility)) {
+
+  auto getRuntimeCompatVersion = [&] () -> Optional<llvm::VersionTuple> {
     Optional<llvm::VersionTuple> runtimeCompatibilityVersion;
-    
     if (auto versionArg = Args.getLastArg(
                                   options::OPT_runtime_compatibility_version)) {
       auto version = StringRef(versionArg->getValue());
@@ -1221,31 +1219,18 @@ static bool ParseIRGenArgs(IRGenOptions &Opts, ArgList &Args,
       runtimeCompatibilityVersion =
                            getSwiftRuntimeCompatibilityVersionForTarget(Triple);
     }
-      
-    Opts.AutolinkRuntimeCompatibilityLibraryVersion =
-                                                    runtimeCompatibilityVersion;
+    return runtimeCompatibilityVersion;
+  };
+
+  // Autolink runtime compatibility libraries, if asked to.
+  if (!Args.hasArg(options::OPT_disable_autolinking_runtime_compatibility)) {
+    Opts.AutolinkRuntimeCompatibilityLibraryVersion = getRuntimeCompatVersion();
   }
 
   if (!Args.hasArg(options::
           OPT_disable_autolinking_runtime_compatibility_dynamic_replacements)) {
-    Optional<llvm::VersionTuple> runtimeCompatibilityVersion;
-    if (auto versionArg =
-            Args.getLastArg(options::OPT_runtime_compatibility_version)) {
-      auto version = StringRef(versionArg->getValue());
-      if (version.equals("none")) {
-        runtimeCompatibilityVersion = None;
-      } else if (version.equals("5.0")) {
-        runtimeCompatibilityVersion = llvm::VersionTuple(5, 0);
-      } else {
-        Diags.diagnose(SourceLoc(), diag::error_invalid_arg_value,
-                       versionArg->getAsString(Args), version);
-      }
-    } else {
-      runtimeCompatibilityVersion =
-          getSwiftRuntimeCompatibilityVersionForTarget(Triple);
-    }
     Opts.AutolinkRuntimeCompatibilityDynamicReplacementLibraryVersion =
-        runtimeCompatibilityVersion;
+        getRuntimeCompatVersion();
   }
   return false;
 }