change EH related stuff (other than EH_LABEL) to use MCSymbol
instead of label ID's.  This cleans up and regularizes a bunch 
of code and makes way for future progress.

Unfortunately, this pointed out to me that JITDwarfEmitter.cpp
is largely copy and paste from DwarfException/MachineModuleInfo
and other places.  This is very sad and disturbing. :(

One major change here is that TidyLandingPads moved from being
called in DwarfException::BeginFunction to being called in
DwarfException::EndFunction.  There should not be any 
functionality change from doing this, but I'm not an EH expert.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98459 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/ExecutionEngine/JIT/JITEmitter.cpp b/lib/ExecutionEngine/JIT/JITEmitter.cpp
index 26353f7..83acb5d 100644
--- a/lib/ExecutionEngine/JIT/JITEmitter.cpp
+++ b/lib/ExecutionEngine/JIT/JITEmitter.cpp
@@ -341,7 +341,7 @@
 
     /// LabelLocations - This vector is a mapping from Label ID's to their
     /// address.
-    std::vector<uintptr_t> LabelLocations;
+    DenseMap<MCSymbol*, uintptr_t> LabelLocations;
 
     /// MMI - Machine module info for exception informations
     MachineModuleInfo* MMI;
@@ -459,16 +459,13 @@
 
     virtual void processDebugLoc(DebugLoc DL, bool BeforePrintingInsn);
 
-    virtual void emitLabel(uint64_t LabelID) {
-      if (LabelLocations.size() <= LabelID)
-        LabelLocations.resize((LabelID+1)*2);
-      LabelLocations[LabelID] = getCurrentPCValue();
+    virtual void emitLabel(MCSymbol *Label) {
+      LabelLocations[Label] = getCurrentPCValue();
     }
 
-    virtual uintptr_t getLabelAddress(uint64_t LabelID) const {
-      assert(LabelLocations.size() > (unsigned)LabelID &&
-             LabelLocations[LabelID] && "Label not emitted!");
-      return LabelLocations[LabelID];
+    virtual uintptr_t getLabelAddress(MCSymbol *Label) const {
+      assert(LabelLocations.count(Label) && "Label not emitted!");
+      return LabelLocations.find(Label)->second;
     }
 
     virtual void setModuleInfo(MachineModuleInfo* Info) {