When associating file ranges of macro arguments with their
macro expansion ranges, make sure to check all the FileID
entries that are contained in the spelling range of the
expansion for the macro argument.

Fixes rdar://12537982

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@166359 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Basic/SourceManager.cpp b/lib/Basic/SourceManager.cpp
index 603b385..cd0284a 100644
--- a/lib/Basic/SourceManager.cpp
+++ b/lib/Basic/SourceManager.cpp
@@ -1705,48 +1705,93 @@
     if (!ExpInfo.isMacroArgExpansion())
       continue;
 
-    SourceLocation SpellLoc = ExpInfo.getSpellingLoc();
-    while (!SpellLoc.isFileID()) {
-      std::pair<FileID, unsigned> LocInfo = getDecomposedLoc(SpellLoc);
-      const ExpansionInfo &Info = getSLocEntry(LocInfo.first).getExpansion();
-      if (!Info.isMacroArgExpansion())
-        break;
-      SpellLoc = Info.getSpellingLoc().getLocWithOffset(LocInfo.second);
-    }
-    if (!SpellLoc.isFileID())
-      continue;
-    
-    unsigned BeginOffs;
-    if (!isInFileID(SpellLoc, FID, &BeginOffs))
-      continue;
-
-    unsigned EndOffs = BeginOffs + getFileIDSize(FileID::get(ID));
-
-    // Add a new chunk for this macro argument. A previous macro argument chunk
-    // may have been lexed again, so e.g. if the map is
-    //     0   -> SourceLocation()
-    //     100 -> Expanded loc #1
-    //     110 -> SourceLocation()
-    // and we found a new macro FileID that lexed from offet 105 with length 3,
-    // the new map will be:
-    //     0   -> SourceLocation()
-    //     100 -> Expanded loc #1
-    //     105 -> Expanded loc #2
-    //     108 -> Expanded loc #1
-    //     110 -> SourceLocation()
-    //
-    // Since re-lexed macro chunks will always be the same size or less of
-    // previous chunks, we only need to find where the ending of the new macro
-    // chunk is mapped to and update the map with new begin/end mappings.
-
-    MacroArgsMap::iterator I = MacroArgsCache.upper_bound(EndOffs);
-    --I;
-    SourceLocation EndOffsMappedLoc = I->second;
-    MacroArgsCache[BeginOffs] = SourceLocation::getMacroLoc(Entry.getOffset());
-    MacroArgsCache[EndOffs] = EndOffsMappedLoc;
+    associateFileChunkWithMacroArgExp(MacroArgsCache, FID,
+                                 ExpInfo.getSpellingLoc(),
+                                 SourceLocation::getMacroLoc(Entry.getOffset()),
+                                 getFileIDSize(FileID::get(ID)));
   }
 }
 
+void SourceManager::associateFileChunkWithMacroArgExp(
+                                         MacroArgsMap &MacroArgsCache,
+                                         FileID FID,
+                                         SourceLocation SpellLoc,
+                                         SourceLocation ExpansionLoc,
+                                         unsigned ExpansionLength) const {
+  if (!SpellLoc.isFileID()) {
+    unsigned SpellBeginOffs = SpellLoc.getOffset();
+    unsigned SpellEndOffs = SpellBeginOffs + ExpansionLength;
+
+    // The spelling range for this macro argument expansion can span multiple
+    // consecutive FileID entries. Go through each entry contained in the
+    // spelling range and if one is itself a macro argument expansion, recurse
+    // and associate the file chunk that it represents.
+
+    FileID SpellFID; // Current FileID in the spelling range.
+    unsigned SpellRelativeOffs;
+    llvm::tie(SpellFID, SpellRelativeOffs) = getDecomposedLoc(SpellLoc);
+    while (1) {
+      const SLocEntry &Entry = getSLocEntry(SpellFID);
+      unsigned SpellFIDBeginOffs = Entry.getOffset();
+      unsigned SpellFIDSize = getFileIDSize(SpellFID);
+      unsigned SpellFIDEndOffs = SpellFIDBeginOffs + SpellFIDSize;
+      const ExpansionInfo &Info = Entry.getExpansion();
+      if (Info.isMacroArgExpansion()) {
+        unsigned CurrSpellLength;
+        if (SpellFIDEndOffs < SpellEndOffs)
+          CurrSpellLength = SpellFIDSize - SpellRelativeOffs;
+        else
+          CurrSpellLength = ExpansionLength;
+        associateFileChunkWithMacroArgExp(MacroArgsCache, FID,
+                      Info.getSpellingLoc().getLocWithOffset(SpellRelativeOffs),
+                      ExpansionLoc, CurrSpellLength);
+      }
+
+      if (SpellFIDEndOffs >= SpellEndOffs)
+        return; // we covered all FileID entries in the spelling range.
+
+      // Move to the next FileID entry in the spelling range.
+      unsigned advance = SpellFIDSize - SpellRelativeOffs + 1;
+      ExpansionLoc = ExpansionLoc.getLocWithOffset(advance);
+      ExpansionLength -= advance;
+      ++SpellFID.ID;
+      SpellRelativeOffs = 0;
+    }
+
+  }
+
+  assert(SpellLoc.isFileID());
+
+  unsigned BeginOffs;
+  if (!isInFileID(SpellLoc, FID, &BeginOffs))
+    return;
+
+  unsigned EndOffs = BeginOffs + ExpansionLength;
+
+  // Add a new chunk for this macro argument. A previous macro argument chunk
+  // may have been lexed again, so e.g. if the map is
+  //     0   -> SourceLocation()
+  //     100 -> Expanded loc #1
+  //     110 -> SourceLocation()
+  // and we found a new macro FileID that lexed from offet 105 with length 3,
+  // the new map will be:
+  //     0   -> SourceLocation()
+  //     100 -> Expanded loc #1
+  //     105 -> Expanded loc #2
+  //     108 -> Expanded loc #1
+  //     110 -> SourceLocation()
+  //
+  // Since re-lexed macro chunks will always be the same size or less of
+  // previous chunks, we only need to find where the ending of the new macro
+  // chunk is mapped to and update the map with new begin/end mappings.
+
+  MacroArgsMap::iterator I = MacroArgsCache.upper_bound(EndOffs);
+  --I;
+  SourceLocation EndOffsMappedLoc = I->second;
+  MacroArgsCache[BeginOffs] = ExpansionLoc;
+  MacroArgsCache[EndOffs] = EndOffsMappedLoc;
+}
+
 /// \brief If \arg Loc points inside a function macro argument, the returned
 /// location will be the macro location in which the argument was expanded.
 /// If a macro argument is used multiple times, the expanded location will