fix a memory leak yjasskin pointed out: MCSymbol is bump pointer
allocated and thus not freed.  This is cool except that it contains
and std::string so the string data didn't get freed.  In any case
there is no reason to redundantly store the string data in the 
MCSymbol anyway, just make the MCSymbol ref the string data in the
MCContext StringMap.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98536 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCContext.cpp b/lib/MC/MCContext.cpp
index ae9a30a..70c89a2 100644
--- a/lib/MC/MCContext.cpp
+++ b/lib/MC/MCContext.cpp
@@ -23,18 +23,25 @@
   // we don't need to free them here.
 }
 
-MCSymbol *MCContext::GetOrCreateSymbol(StringRef Name) {
+MCSymbol *MCContext::GetOrCreateSymbol(StringRef Name, bool isTemporary) {
   assert(!Name.empty() && "Normal symbols cannot be unnamed!");
-  MCSymbol *&Entry = Symbols[Name];
-  if (Entry) return Entry;
+  
+  // Do the lookup and get the entire StringMapEntry.  We want access to the
+  // key if we are creating the entry.
+  StringMapEntry<MCSymbol*> &Entry = Symbols.GetOrCreateValue(Name);
+  if (Entry.getValue()) return Entry.getValue();
 
-  return Entry = new (*this) MCSymbol(Name, false);
+  // Ok, the entry doesn't already exist.  Have the MCSymbol object itself refer
+  // to the copy of the string that is embedded in the StringMapEntry.
+  MCSymbol *Result = new (*this) MCSymbol(Entry.getKey(), isTemporary);
+  Entry.setValue(Result);
+  return Result; 
 }
 
-MCSymbol *MCContext::GetOrCreateSymbol(const Twine &Name) {
+MCSymbol *MCContext::GetOrCreateSymbol(const Twine &Name, bool isTemporary) {
   SmallString<128> NameSV;
   Name.toVector(NameSV);
-  return GetOrCreateSymbol(NameSV.str());
+  return GetOrCreateSymbol(NameSV.str(), isTemporary);
 }
 
 MCSymbol *MCContext::CreateTempSymbol() {
@@ -50,10 +57,7 @@
     return GetOrCreateTemporarySymbol(Twine(MAI.getPrivateGlobalPrefix()) +
                                       "tmp" + Twine(NextUniqueID++));
   
-  // Otherwise create as usual.
-  MCSymbol *&Entry = Symbols[Name];
-  if (Entry) return Entry;
-  return Entry = new (*this) MCSymbol(Name, true);
+  return GetOrCreateSymbol(Name, true);
 }
 
 MCSymbol *MCContext::GetOrCreateTemporarySymbol(const Twine &Name) {