Add doesActionPerformEndOfPipelineActions

For now, force the clang-based actions to skip the end of the pipeline. This restores the previous behavior of the frontend, but may not be desirable in the long run. For example, one may want to dump clang stats after running an -emit-pch job, but that is impossible without forcing the end of the pipeline to be more tolerant of ObjCHeader/modulemap-only inputs.

rdar://68587228

Author: CodaFi

include/swift/Frontend/FrontendOptions.h

@@ -304,6 +304,9 @@ class FrontendOptions {
   /// \return true if the given action requires input files to be provided.
   static bool doesActionRequireInputs(ActionType action);
 
+  /// \return true if the given action requires input files to be provided.
+  static bool doesActionPerformEndOfPipelineActions(ActionType action);
+
   /// Return a hash code of any components from these options that should
   /// contribute to a Swift Bridging PCH hash.
   llvm::hash_code getPCHHashComponents() const {

lib/Frontend/FrontendOptions.cpp

@@ -42,8 +42,8 @@ bool FrontendOptions::needsProperModuleName(ActionType action) {
   case ActionType::DumpScopeMaps:
   case ActionType::DumpTypeRefinementContexts:
   case ActionType::DumpPCM:
-    return false;
   case ActionType::EmitPCH:
+    return false;
   case ActionType::EmitSILGen:
   case ActionType::EmitSIL:
   case ActionType::EmitSIBGen:
@@ -171,6 +171,47 @@ bool FrontendOptions::doesActionRequireInputs(ActionType action) {
   llvm_unreachable("Unknown ActionType");
 }
 
+bool FrontendOptions::doesActionPerformEndOfPipelineActions(ActionType action) {
+  switch (action) {
+  case ActionType::NoneAction:
+  case ActionType::PrintVersion:
+  case ActionType::EmitPCH:
+  case ActionType::EmitPCM:
+  case ActionType::DumpPCM:
+    return false;
+  case ActionType::REPL:
+  case ActionType::Parse:
+  case ActionType::DumpParse:
+  case ActionType::EmitSyntax:
+  case ActionType::DumpInterfaceHash:
+  case ActionType::EmitImportedModules:
+  case ActionType::ScanDependencies:
+  case ActionType::ScanClangDependencies:
+  case ActionType::CompileModuleFromInterface:
+  case ActionType::TypecheckModuleFromInterface:
+  case ActionType::ResolveImports:
+  case ActionType::Typecheck:
+  case ActionType::DumpAST:
+  case ActionType::PrintAST:
+  case ActionType::DumpScopeMaps:
+  case ActionType::DumpTypeRefinementContexts:
+  case ActionType::EmitSILGen:
+  case ActionType::EmitSIL:
+  case ActionType::EmitModuleOnly:
+  case ActionType::MergeModules:
+  case ActionType::EmitSIBGen:
+  case ActionType::EmitSIB:
+  case ActionType::Immediate:
+  case ActionType::EmitAssembly:
+  case ActionType::EmitIR:
+  case ActionType::EmitBC:
+  case ActionType::EmitObject:
+  case ActionType::DumpTypeInfo:
+    return true;
+  }
+  llvm_unreachable("Unknown ActionType");
+}
+
 void FrontendOptions::forAllOutputPaths(
     const InputFile &input, llvm::function_ref<void(StringRef)> fn) const {
   if (RequestedAction != FrontendOptions::ActionType::EmitModuleOnly &&

lib/FrontendTool/FrontendTool.cpp

@@ -1876,8 +1876,6 @@ static bool performAction(CompilerInstance &Instance,
                              "removed; use the LLDB-enhanced REPL instead.");
 
   // MARK: Actions for Clang and Clang Modules
-  // We've been asked to precompile a bridging header or module; we want to
-  // avoid touching any other inputs and just parse, emit and exit.
   case FrontendOptions::ActionType::EmitPCH:
     return precompileBridgingHeader(Instance);
   case FrontendOptions::ActionType::EmitPCM:
@@ -1983,7 +1981,7 @@ static bool performCompile(CompilerInstance &Instance,
   const FrontendOptions::ActionType Action = opts.RequestedAction;
 
   // To compile LLVM IR, just pass it off unmodified.
-  if (Instance.getInvocation().getInputKind() == InputFileKind::LLVM)
+  if (Invocation.getInputKind() == InputFileKind::LLVM)
     return compileLLVMIR(Instance);
 
   // If we aren't in a parse-only context and expect an implicit stdlib import,
@@ -2014,7 +2012,7 @@ static bool performCompile(CompilerInstance &Instance,
   // We might have freed the ASTContext already, but in that case we would
   // have already performed these actions.
   if (Instance.hasASTContext() &&
-      FrontendOptions::doesActionRequireInputs(Action)) {
+      FrontendOptions::doesActionPerformEndOfPipelineActions(Action)) {
     performEndOfPipelineActions(Instance);
     hadError |= Instance.getASTContext().hadError();
   }