Basic/Diagnostics: Add a DiagnosticMappingInfo helper class, and switch to

storing mappings with that instead of straying some magic constants about the
source.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@140760 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 54 insertions, 24 deletions

diff --git a/include/clang/Basic/Diagnostic.h b/include/clang/Basic/Diagnostic.h
index 4136b5cc05..a0573c03f0 100644
--- a/include/clang/Basic/Diagnostic.h
+++ b/include/clang/Basic/Diagnostic.h
@@ -175,18 +175,21 @@ private:
   /// the state so that we know what is the diagnostic state at any given
   /// source location.
   class DiagState {
-    llvm::DenseMap<unsigned, unsigned> DiagMap;
+    llvm::DenseMap<unsigned, DiagnosticMappingInfo> DiagMap;
 
   public:
-    typedef llvm::DenseMap<unsigned, unsigned>::const_iterator iterator;
+    typedef llvm::DenseMap<unsigned, DiagnosticMappingInfo>::const_iterator
+      iterator;
 
-    void setMapping(diag::kind Diag, unsigned Map) { DiagMap[Diag] = Map; }
+    void setMappingInfo(diag::kind Diag, DiagnosticMappingInfo Info) {
+      DiagMap[Diag] = Info;
+    }
 
-    diag::Mapping getMapping(diag::kind Diag) const {
+    DiagnosticMappingInfo getMappingInfo(diag::kind Diag) const {
       iterator I = DiagMap.find(Diag);
       if (I != DiagMap.end())
-        return (diag::Mapping)I->second;
-      return diag::Mapping();
+        return I->second;
+      return DiagnosticMappingInfo::MakeUnset();
     }
 
     iterator begin() const { return DiagMap.begin(); }
@@ -563,12 +566,11 @@ private:
   /// \brief Report the delayed diagnostic.
   void ReportDelayed();
 
-  void setDiagnosticMappingInternal(unsigned DiagId, unsigned Map,
+  void setDiagnosticMappingInternal(unsigned DiagId, diag::Mapping Map,
                                     DiagState *State,
                                     bool isUser, bool isPragma) const {
-    if (isUser) Map |= 8;  // Set the high bit for user mappings.
-    if (isPragma) Map |= 0x10;  // Set the bit for diagnostic pragma mappings.
-    State->setMapping((diag::kind)DiagId, Map);
+    State->setMappingInfo((diag::kind)DiagId, DiagnosticMappingInfo::MakeInfo(
+                            Map, isUser, isPragma));
   }
 
   // This is private state used by DiagnosticBuilder.  We put it here instead of
diff --git a/include/clang/Basic/DiagnosticIDs.h b/include/clang/Basic/DiagnosticIDs.h
index c50bc662fb..f11293c6c8 100644
--- a/include/clang/Basic/DiagnosticIDs.h
+++ b/include/clang/Basic/DiagnosticIDs.h
@@ -74,6 +74,34 @@ namespace clang {
     };
   }
 
+class DiagnosticMappingInfo {
+  unsigned Mapping : 3;
+  unsigned IsUser : 1;
+  unsigned IsPragma : 1;
+
+public:
+  static DiagnosticMappingInfo MakeUnset() {
+    DiagnosticMappingInfo Result;
+    Result.Mapping = Result.IsUser = Result.IsPragma = 0;
+    return Result;
+  }
+
+  static DiagnosticMappingInfo MakeInfo(diag::Mapping Mapping,
+                                        bool IsUser, bool IsPragma) {
+    DiagnosticMappingInfo Result;
+    Result.Mapping = Mapping;
+    Result.IsUser = IsUser;
+    Result.IsPragma = IsPragma;
+    return Result;
+  }
+
+  diag::Mapping getMapping() const { return diag::Mapping(Mapping); }
+  bool isUser() const { return IsUser; }
+  bool isPragma() const { return IsPragma; }
+
+  bool isUnset() const { return Mapping == 0; }
+};
+
 /// \brief Used for handling and querying diagnostic IDs. Can be used and shared
 /// by multiple Diagnostics for multiple translation units.
 class DiagnosticIDs : public llvm::RefCountedBase<DiagnosticIDs> {
diff --git a/lib/Basic/DiagnosticIDs.cpp b/lib/Basic/DiagnosticIDs.cpp
index d8a0afc1cc..45d5102714 100644
--- a/lib/Basic/DiagnosticIDs.cpp
+++ b/lib/Basic/DiagnosticIDs.cpp
@@ -183,10 +183,10 @@ static const StaticDiagInfoRec *GetDiagInfo(unsigned DiagID) {
   return Found;
 }
 
-static unsigned GetDefaultDiagMapping(unsigned DiagID) {
+static diag::Mapping GetDefaultDiagMapping(unsigned DiagID) {
   if (const StaticDiagInfoRec *Info = GetDiagInfo(DiagID)) {
     // Compute the effective mapping based on the extra bits.
-    unsigned Mapping = Info->Mapping;
+    diag::Mapping Mapping = (diag::Mapping) Info->Mapping;
 
     if (Info->WarnNoWerror) {
       assert(Mapping == diag::MAP_WARNING &&
@@ -507,20 +507,21 @@ DiagnosticIDs::getDiagnosticLevel(unsigned DiagID, unsigned DiagClass,
   DiagnosticsEngine::DiagState *State = Pos->State;
 
   // Get the mapping information, if unset, compute it lazily.
-  unsigned MappingInfo = State->getMapping((diag::kind) DiagID);
-  if (MappingInfo == 0) {
-    MappingInfo = GetDefaultDiagMapping(DiagID);
-    Diag.setDiagnosticMappingInternal(DiagID, MappingInfo, State, false, false);
+  DiagnosticMappingInfo MappingInfo = State->getMappingInfo((diag::kind)DiagID);
+  if (MappingInfo.isUnset()) {
+    MappingInfo = DiagnosticMappingInfo::MakeInfo(
+      GetDefaultDiagMapping(DiagID), /*IsUser=*/false, /*IsPragma=*/false);
+    State->setMappingInfo((diag::kind) DiagID, MappingInfo);
   }
 
   bool ShouldEmitInSystemHeader = false;
 
-  switch (MappingInfo & 7) {
+  switch (MappingInfo.getMapping()) {
   default: llvm_unreachable("Unknown mapping!");
   case diag::MAP_IGNORE:
     if (Diag.EnableAllWarnings) {
       // Leave the warning disabled if it was explicitly ignored.
-      if ((MappingInfo & 8) != 0)
+      if (MappingInfo.isUser())
         return DiagnosticIDs::Ignored;
      
       Result = Diag.WarningsAsErrors ? DiagnosticIDs::Error 
@@ -530,7 +531,7 @@ DiagnosticIDs::getDiagnosticLevel(unsigned DiagID, unsigned DiagClass,
     // and we're mapping them onto warnings or errors.
     else if (!isBuiltinExtensionDiag(DiagID) ||  // Not an extension
              Diag.ExtBehavior == DiagnosticsEngine::Ext_Ignore || // Ext ignored
-             (MappingInfo & 8) != 0) {           // User explicitly mapped it.
+             MappingInfo.isUser()) {           // User explicitly mapped it.
       return DiagnosticIDs::Ignored;
     }
     else {
@@ -563,7 +564,7 @@ DiagnosticIDs::getDiagnosticLevel(unsigned DiagID, unsigned DiagClass,
     // If this is an extension diagnostic and we're in -pedantic-error mode, and
     // if the user didn't explicitly map it, upgrade to an error.
     if (Diag.ExtBehavior == DiagnosticsEngine::Ext_Error &&
-        (MappingInfo & 8) == 0 &&
+        !MappingInfo.isUser() &&
         isBuiltinExtensionDiag(DiagID))
       Result = DiagnosticIDs::Error;
 
diff --git a/lib/Serialization/ASTWriter.cpp b/lib/Serialization/ASTWriter.cpp
index 5f005a0106..1232900be3 100644
--- a/lib/Serialization/ASTWriter.cpp
+++ b/lib/Serialization/ASTWriter.cpp
@@ -1815,10 +1815,9 @@ void ASTWriter::WritePragmaDiagnosticMappings(const DiagnosticsEngine &Diag) {
     Record.push_back(point.Loc.getRawEncoding());
     for (DiagnosticsEngine::DiagState::iterator
            I = point.State->begin(), E = point.State->end(); I != E; ++I) {
-      unsigned diag = I->first, map = I->second;
-      if (map & 0x10) { // mapping from a diagnostic pragma.
-        Record.push_back(diag);
-        Record.push_back(map & 0x7);
+      if (I->second.isPragma()) {
+        Record.push_back(I->first);
+        Record.push_back(I->second.getMapping());
       }
     }
     Record.push_back(-1); // mark the end of the diag/map pairs for this