3 files changed, 98 insertions, 6 deletions

diff --git a/llvm/include/llvm/Analysis/OptimizationDiagnosticInfo.h b/llvm/include/llvm/Analysis/OptimizationDiagnosticInfo.h
index 4c3b0fb949b..aae1b2c1b0c 100644
--- a/llvm/include/llvm/Analysis/OptimizationDiagnosticInfo.h
+++ b/llvm/include/llvm/Analysis/OptimizationDiagnosticInfo.h
@@ -24,7 +24,6 @@
 
 namespace llvm {
 class DebugLoc;
-class LLVMContext;
 class Loop;
 class Pass;
 class Twine;
@@ -71,6 +70,21 @@ public:
   /// optimization record file.
   void emit(DiagnosticInfoOptimizationBase &OptDiag);
 
+  /// \brief Take a lambda that returns a remark which will be emitted.  Second
+  /// argument is only used to restrict this to functions.
+  template <typename T>
+  void emit(T RemarkBuilder, decltype(RemarkBuilder()) * = nullptr) {
+    // Avoid building the remark unless we know there are at least *some*
+    // remarks enabled. We can't currently check whether remarks are requested
+    // for the calling pass since that requires actually building the remark.
+
+    if (F->getContext().getDiagnosticsOutputFile() ||
+        F->getContext().getDiagHandlerPtr()->isAnyRemarkEnabled()) {
+      auto R = RemarkBuilder();
+      emit(R);
+    }
+  }
+
   /// \brief Whether we allow for extra compile-time budget to perform more
   /// analysis to produce fewer false positives.
   ///
diff --git a/llvm/include/llvm/IR/DiagnosticHandler.h b/llvm/include/llvm/IR/DiagnosticHandler.h
index c9a606f02f7..9256d4850df 100644
--- a/llvm/include/llvm/IR/DiagnosticHandler.h
+++ b/llvm/include/llvm/IR/DiagnosticHandler.h
@@ -60,12 +60,15 @@ struct DiagnosticHandler {
   /// to provide different implementation.
   virtual bool isPassedOptRemarkEnabled(StringRef PassName) const;
 
-  /// Return true if any type of remarks are enabled.
+  /// Return true if any type of remarks are enabled for this pass.
   bool isAnyRemarkEnabled(StringRef PassName) const {
     return (isMissedOptRemarkEnabled(PassName) ||
             isPassedOptRemarkEnabled(PassName) ||
             isAnalysisRemarkEnabled(PassName));
   }
+
+  /// Return true if any type of remarks are enabled for any pass.
+  virtual bool isAnyRemarkEnabled() const;
 };
 } // namespace llvm
 
diff --git a/llvm/include/llvm/IR/DiagnosticInfo.h b/llvm/include/llvm/IR/DiagnosticInfo.h
index a2023554a89..1e9bcb67e28 100644
--- a/llvm/include/llvm/IR/DiagnosticInfo.h
+++ b/llvm/include/llvm/IR/DiagnosticInfo.h
@@ -438,10 +438,10 @@ public:
       : DiagnosticInfoWithLocationBase(Kind, Severity, Fn, Loc),
         PassName(PassName), RemarkName(RemarkName) {}
 
-  DiagnosticInfoOptimizationBase &operator<<(StringRef S);
-  DiagnosticInfoOptimizationBase &operator<<(Argument A);
-  DiagnosticInfoOptimizationBase &operator<<(setIsVerbose V);
-  DiagnosticInfoOptimizationBase &operator<<(setExtraArgs EA);
+  void insert(StringRef S);
+  void insert(Argument A);
+  void insert(setIsVerbose V);
+  void insert(setExtraArgs EA);
 
   /// \see DiagnosticInfo::print.
   void print(DiagnosticPrinter &DP) const override;
@@ -511,6 +511,81 @@ protected:
   friend struct yaml::MappingTraits<DiagnosticInfoOptimizationBase *>;
 };
 
+/// Allow the insertion operator to return the actual remark type rather than a
+/// common base class.  This allows returning the result of the insertion
+/// directly by value, e.g. return OptimizationRemarkAnalysis(...) << "blah".
+template <class RemarkT>
+RemarkT &
+operator<<(RemarkT &R,
+           typename std::enable_if<
+               std::is_base_of<DiagnosticInfoOptimizationBase, RemarkT>::value,
+               StringRef>::type S) {
+  R.insert(S);
+  return R;
+}
+
+/// Also allow r-value for the remark to allow insertion into a
+/// temporarily-constructed remark.
+template <class RemarkT>
+RemarkT &
+operator<<(RemarkT &&R,
+           typename std::enable_if<
+               std::is_base_of<DiagnosticInfoOptimizationBase, RemarkT>::value,
+               StringRef>::type S) {
+  R.insert(S);
+  return R;
+}
+
+template <class RemarkT>
+RemarkT &
+operator<<(RemarkT &R,
+           typename std::enable_if<
+               std::is_base_of<DiagnosticInfoOptimizationBase, RemarkT>::value,
+               DiagnosticInfoOptimizationBase::Argument>::type A) {
+  R.insert(A);
+  return R;
+}
+
+template <class RemarkT>
+RemarkT &
+operator<<(RemarkT &&R,
+           typename std::enable_if<
+               std::is_base_of<DiagnosticInfoOptimizationBase, RemarkT>::value,
+               DiagnosticInfoOptimizationBase::Argument>::type A) {
+  R.insert(A);
+  return R;
+}
+
+template <class RemarkT>
+RemarkT &
+operator<<(RemarkT &R,
+           typename std::enable_if<
+               std::is_base_of<DiagnosticInfoOptimizationBase, RemarkT>::value,
+               DiagnosticInfoOptimizationBase::setIsVerbose>::type V) {
+  R.insert(V);
+  return R;
+}
+
+template <class RemarkT>
+RemarkT &
+operator<<(RemarkT &&R,
+           typename std::enable_if<
+               std::is_base_of<DiagnosticInfoOptimizationBase, RemarkT>::value,
+               DiagnosticInfoOptimizationBase::setIsVerbose>::type V) {
+  R.insert(V);
+  return R;
+}
+
+template <class RemarkT>
+RemarkT &
+operator<<(RemarkT &R,
+           typename std::enable_if<
+               std::is_base_of<DiagnosticInfoOptimizationBase, RemarkT>::value,
+               DiagnosticInfoOptimizationBase::setExtraArgs>::type EA) {
+  R.insert(EA);
+  return R;
+}
+
 /// \brief Common features for diagnostics dealing with optimization remarks
 /// that are used by IR passes.
 class DiagnosticInfoIROptimization : public DiagnosticInfoOptimizationBase {