Raise the ARCMT functionality in Clang into proper FrontendActions.

These are somewhat special in that they wrap any other FrontendAction,
running various ARC transformations or checks prior to the standard
action's run. To implement them easily, this extends FrontendAction to
have a WrapperFrontendAction utility class which forwards all calls by
default to an inner action setup at construction time. This is then
subclassed to override the specific behavior needed by the different
ARCMT tools.

Finally, FrontendTool is taught how to create these wrapper actions from
the existing flags and options structures.

The result is that clangFrontend no longer depends on clangARCMigrate.
This is very important, as clangARCMigrate *heavily* depends on
clangFrontend. Fundamentally ARCMigrate is at the same layer as
a library like Rewrite, sitting firmly on top of the Frontend, but tied
together with the FrontendTool when building the clang binary itself.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@133161 91177308-0d34-0410-b5e6-96231b3b80d8

9 files changed, 191 insertions, 31 deletions

diff --git a/include/clang/ARCMigrate/ARCMTActions.h b/include/clang/ARCMigrate/ARCMTActions.h
new file mode 100644
index 0000000000..d2d9410b32
--- /dev/null
+++ b/include/clang/ARCMigrate/ARCMTActions.h
@@ -0,0 +1,46 @@
+//===--- ARCMTActions.h - ARC Migrate Tool Frontend Actions -----*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_ARCMIGRATE_ARCMT_ACTION_H
+#define LLVM_CLANG_ARCMIGRATE_ARCMT_ACTION_H
+
+#include "clang/Frontend/FrontendAction.h"
+#include "llvm/ADT/OwningPtr.h"
+
+namespace clang {
+namespace arcmt {
+
+class CheckAction : public WrapperFrontendAction {
+protected:
+  virtual void ExecuteAction();
+
+public:
+  CheckAction(FrontendAction *WrappedAction);
+};
+
+class TransformationAction : public WrapperFrontendAction {
+protected:
+  virtual void ExecuteAction();
+
+public:
+  TransformationAction(FrontendAction *WrappedAction);
+};
+
+class InMemoryTransformationAction : public WrapperFrontendAction {
+protected:
+  virtual void ExecuteAction();
+
+public:
+  InMemoryTransformationAction(FrontendAction *WrappedAction);
+};
+
+}
+}
+
+#endif
diff --git a/include/clang/Frontend/FrontendAction.h b/include/clang/Frontend/FrontendAction.h
index ee0863a477..2538f55aaf 100644
--- a/include/clang/Frontend/FrontendAction.h
+++ b/include/clang/Frontend/FrontendAction.h
@@ -51,6 +51,7 @@ class FrontendAction {
   llvm::OwningPtr<ASTUnit> CurrentASTUnit;
   CompilerInstance *Instance;
   friend class ASTMergeAction;
+  friend class WrapperFrontendAction;
 
 private:
   ASTConsumer* CreateWrappedASTConsumer(CompilerInstance &CI,
@@ -253,6 +254,35 @@ public:
   virtual bool usesPreprocessorOnly() const { return true; }
 };
 
+/// WrapperFrontendAction - A frontend action which simply wraps some other
+/// runtime specified frontend action. Deriving from this class allows an
+/// action to inject custom logic around some existing action's behavior. It
+/// implements every virtual method in the FrontendAction interface by
+/// forwarding to the wrapped action.
+class WrapperFrontendAction : public FrontendAction {
+  llvm::OwningPtr<FrontendAction> WrappedAction;
+
+protected:
+  virtual ASTConsumer *CreateASTConsumer(CompilerInstance &CI,
+                                         llvm::StringRef InFile);
+  virtual bool BeginSourceFileAction(CompilerInstance &CI,
+                                     llvm::StringRef Filename);
+  virtual void ExecuteAction();
+  virtual void EndSourceFileAction();
+
+public:
+  /// Construct a WrapperFrontendAction from an existing action, taking
+  /// ownership of it.
+  WrapperFrontendAction(FrontendAction *WrappedAction);
+
+  virtual bool usesPreprocessorOnly() const;
+  virtual bool usesCompleteTranslationUnit();
+  virtual bool hasPCHSupport() const;
+  virtual bool hasASTFileSupport() const;
+  virtual bool hasIRSupport() const;
+  virtual bool hasCodeCompletionSupport() const;
+};
+
 }  // end namespace clang
 
 #endif
diff --git a/lib/ARCMigrate/ARCMTActions.cpp b/lib/ARCMigrate/ARCMTActions.cpp
new file mode 100644
index 0000000000..a30c2783e3
--- /dev/null
+++ b/lib/ARCMigrate/ARCMTActions.cpp
@@ -0,0 +1,58 @@
+//===--- ARCMTActions.cpp - ARC Migrate Tool Frontend Actions ---*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/ARCMigrate/ARCMTActions.h"
+#include "clang/ARCMigrate/ARCMT.h"
+#include "clang/Frontend/CompilerInstance.h"
+
+using namespace clang;
+using namespace arcmt;
+
+void CheckAction::ExecuteAction() {
+  CompilerInstance &CI = getCompilerInstance();
+  if (arcmt::checkForManualIssues(CI.getInvocation(), getCurrentFile(),
+                                  getCurrentFileKind(),
+                                  CI.getDiagnostics().getClient()))
+    return;
+
+  // We only want to see warnings reported from arcmt::checkForManualIssues.
+  CI.getDiagnostics().setIgnoreAllWarnings(true);
+  WrapperFrontendAction::ExecuteAction();
+}
+
+CheckAction::CheckAction(FrontendAction *WrappedAction)
+  : WrapperFrontendAction(WrappedAction) {}
+
+void TransformationAction::ExecuteAction() {
+  CompilerInstance &CI = getCompilerInstance();
+  if (arcmt::applyTransformations(CI.getInvocation(), getCurrentFile(),
+                                  getCurrentFileKind(),
+                                  CI.getDiagnostics().getClient()))
+    return;
+
+  WrapperFrontendAction::ExecuteAction();
+}
+
+TransformationAction::TransformationAction(FrontendAction *WrappedAction)
+  : WrapperFrontendAction(WrappedAction) {}
+
+void InMemoryTransformationAction::ExecuteAction() {
+  CompilerInstance &CI = getCompilerInstance();
+  if (arcmt::applyTransformationsInMemory(CI.getInvocation(), getCurrentFile(),
+                                          getCurrentFileKind(),
+                                          CI.getDiagnostics().getClient()))
+    return;
+
+  WrapperFrontendAction::ExecuteAction();
+}
+
+InMemoryTransformationAction::InMemoryTransformationAction(
+    FrontendAction *WrappedAction)
+  : WrapperFrontendAction(WrappedAction) {}
+
diff --git a/lib/ARCMigrate/CMakeLists.txt b/lib/ARCMigrate/CMakeLists.txt
index 3645a22356..0049d2ff37 100644
--- a/lib/ARCMigrate/CMakeLists.txt
+++ b/lib/ARCMigrate/CMakeLists.txt
@@ -2,6 +2,7 @@ set(LLVM_USED_LIBS clangBasic clangAST clangParse clangFrontend clangRewrite)
 
 add_clang_library(clangARCMigrate
   ARCMT.cpp
+  ARCMTActions.cpp
   FileRemapper.cpp
   TransformActions.cpp
   Transforms.cpp
diff --git a/lib/Frontend/CMakeLists.txt b/lib/Frontend/CMakeLists.txt
index 5565b7b4a8..7dcbebff39 100644
--- a/lib/Frontend/CMakeLists.txt
+++ b/lib/Frontend/CMakeLists.txt
@@ -1,5 +1,4 @@
 set( LLVM_USED_LIBS
-  clangARCMigrate
   clangAST
   clangBasic
   clangDriver
diff --git a/lib/Frontend/CompilerInstance.cpp b/lib/Frontend/CompilerInstance.cpp
index b05c24a985..38fcfe3c47 100644
--- a/lib/Frontend/CompilerInstance.cpp
+++ b/lib/Frontend/CompilerInstance.cpp
@@ -26,7 +26,6 @@
 #include "clang/Frontend/TextDiagnosticPrinter.h"
 #include "clang/Frontend/VerifyDiagnosticsClient.h"
 #include "clang/Frontend/Utils.h"
-#include "clang/ARCMigrate/ARCMT.h"
 #include "clang/Serialization/ASTReader.h"
 #include "clang/Sema/CodeCompleteConsumer.h"
 #include "llvm/Support/FileSystem.h"
@@ -597,34 +596,6 @@ bool CompilerInstance::ExecuteAction(FrontendAction &Act) {
     if (hasSourceManager())
       getSourceManager().clearIDTables();
 
-    switch (getFrontendOpts().ARCMTAction) {
-    default:
-      break;
-
-    case FrontendOptions::ARCMT_Check:
-      if (arcmt::checkForManualIssues(getInvocation(), InFile,
-                                      getFrontendOpts().Inputs[i].first,
-                                      getDiagnostics().getClient()))
-        continue;
-      // We only want to see warnings reported from arcmt::checkForManualIssues.
-      getDiagnostics().setIgnoreAllWarnings(true);
-      break;
-
-    case FrontendOptions::ARCMT_Modify:
-      if (arcmt::applyTransformations(getInvocation(), InFile,
-                                      getFrontendOpts().Inputs[i].first,
-                                      getDiagnostics().getClient()))
-        continue;
-      break;
-
-    case FrontendOptions::ARCMT_ModifyInMemory:
-      if (arcmt::applyTransformationsInMemory(getInvocation(), InFile,
-                                              getFrontendOpts().Inputs[i].first,
-                                              getDiagnostics().getClient()))
-        continue;
-      break;
-    }
-
     if (Act.BeginSourceFile(*this, InFile, getFrontendOpts().Inputs[i].first)) {
       Act.Execute();
       Act.EndSourceFile();
diff --git a/lib/Frontend/FrontendAction.cpp b/lib/Frontend/FrontendAction.cpp
index 42da44c2c7..0024818ad8 100644
--- a/lib/Frontend/FrontendAction.cpp
+++ b/lib/Frontend/FrontendAction.cpp
@@ -381,3 +381,41 @@ PreprocessorFrontendAction::CreateASTConsumer(CompilerInstance &CI,
                                               llvm::StringRef InFile) {
   llvm_unreachable("Invalid CreateASTConsumer on preprocessor action!");
 }
+
+ASTConsumer *WrapperFrontendAction::CreateASTConsumer(CompilerInstance &CI,
+                                                      llvm::StringRef InFile) {
+  return WrappedAction->CreateASTConsumer(CI, InFile);
+}
+bool WrapperFrontendAction::BeginSourceFileAction(CompilerInstance &CI,
+                                                  llvm::StringRef Filename) {
+  return WrappedAction->BeginSourceFileAction(CI, Filename);
+}
+void WrapperFrontendAction::ExecuteAction() {
+  WrappedAction->ExecuteAction();
+}
+void WrapperFrontendAction::EndSourceFileAction() {
+  WrappedAction->EndSourceFileAction();
+}
+
+bool WrapperFrontendAction::usesPreprocessorOnly() const {
+  return WrappedAction->usesPreprocessorOnly();
+}
+bool WrapperFrontendAction::usesCompleteTranslationUnit() {
+  return WrappedAction->usesCompleteTranslationUnit();
+}
+bool WrapperFrontendAction::hasPCHSupport() const {
+  return WrappedAction->hasPCHSupport();
+}
+bool WrapperFrontendAction::hasASTFileSupport() const {
+  return WrappedAction->hasASTFileSupport();
+}
+bool WrapperFrontendAction::hasIRSupport() const {
+  return WrappedAction->hasIRSupport();
+}
+bool WrapperFrontendAction::hasCodeCompletionSupport() const {
+  return WrappedAction->hasCodeCompletionSupport();
+}
+
+WrapperFrontendAction::WrapperFrontendAction(FrontendAction *WrappedAction)
+  : WrappedAction(WrappedAction) {}
+
diff --git a/lib/FrontendTool/CMakeLists.txt b/lib/FrontendTool/CMakeLists.txt
index 720ce2adf1..b8e4329c07 100644
--- a/lib/FrontendTool/CMakeLists.txt
+++ b/lib/FrontendTool/CMakeLists.txt
@@ -1,5 +1,6 @@
 set(LLVM_USED_LIBS clangDriver clangFrontend clangRewrite clangCodeGen 
-    clangStaticAnalyzerFrontend clangStaticAnalyzerCheckers clangStaticAnalyzerCore)
+    clangStaticAnalyzerFrontend clangStaticAnalyzerCheckers clangStaticAnalyzerCore
+    clangARCMigrate)
 
 add_clang_library(clangFrontendTool
   ExecuteCompilerInvocation.cpp
diff --git a/lib/FrontendTool/ExecuteCompilerInvocation.cpp b/lib/FrontendTool/ExecuteCompilerInvocation.cpp
index 664b53351d..7ad263e14b 100644
--- a/lib/FrontendTool/ExecuteCompilerInvocation.cpp
+++ b/lib/FrontendTool/ExecuteCompilerInvocation.cpp
@@ -14,6 +14,7 @@
 
 #include "clang/FrontendTool/Utils.h"
 #include "clang/StaticAnalyzer/Frontend/FrontendActions.h"
+#include "clang/ARCMigrate/ARCMTActions.h"
 #include "clang/CodeGen/CodeGenAction.h"
 #include "clang/Driver/CC1Options.h"
 #include "clang/Driver/OptTable.h"
@@ -89,6 +90,21 @@ static FrontendAction *CreateFrontendAction(CompilerInstance &CI) {
   if (!Act)
     return 0;
 
+  // Potentially wrap the base FE action in an ARC Migrate Tool action.
+  switch (CI.getFrontendOpts().ARCMTAction) {
+  case FrontendOptions::ARCMT_None:
+    break;
+  case FrontendOptions::ARCMT_Check:
+    Act = new arcmt::CheckAction(Act);
+    break;
+  case FrontendOptions::ARCMT_Modify:
+    Act = new arcmt::TransformationAction(Act);
+    break;
+  case FrontendOptions::ARCMT_ModifyInMemory:
+    Act = new arcmt::InMemoryTransformationAction(Act);
+    break;
+  }
+
   // If there are any AST files to merge, create a frontend action
   // adaptor to perform the merge.
   if (!CI.getFrontendOpts().ASTMergeFiles.empty())