1 files changed, 12 insertions, 0 deletions
diff --git a/lib/Lex/MacroInfo.cpp b/lib/Lex/MacroInfo.cpp
index 7a4964f7d2..ffe31f24d3 100644
--- a/lib/Lex/MacroInfo.cpp
+++ b/lib/Lex/MacroInfo.cpp
@@ -58,6 +58,18 @@ MacroInfo::MacroInfo(const MacroInfo &MI, llvm::BumpPtrAllocator &PPAllocator)
   setArgumentList(MI.ArgumentList, MI.NumArguments, PPAllocator);
 }
 
+const MacroInfo *MacroInfo::findDefinitionAtLoc(SourceLocation L,
+                                                SourceManager &SM) const {
+  assert(L.isValid() && "SourceLocation is invalid.");
+  for (const MacroInfo *MI = this; MI; MI = MI->PreviousDefinition) {
+    if (MI->Location.isInvalid() ||  // For macros defined on the command line.
+        SM.isBeforeInTranslationUnit(MI->Location, L))
+      return (MI->UndefLocation.isInvalid() ||
+              SM.isBeforeInTranslationUnit(L, MI->UndefLocation)) ? MI : NULL;
+  }
+  return NULL;
+}
+
 unsigned MacroInfo::getDefinitionLengthSlow(SourceManager &SM) const {
   assert(!IsDefinitionLengthCached);
   IsDefinitionLengthCached = true;