add new apis for getting/setting !dbg metadata on 
instructions.  In addition to being a convenience,
they are faster than the old apis, particularly when
not going from an MDKindID like people should be
doing.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99982 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/FastISel.cpp b/lib/CodeGen/SelectionDAG/FastISel.cpp
index 3fc30ff..e4e9ef4 100644
--- a/lib/CodeGen/SelectionDAG/FastISel.cpp
+++ b/lib/CodeGen/SelectionDAG/FastISel.cpp
@@ -340,10 +340,9 @@
       StaticAllocaMap.find(AI);
     if (SI == StaticAllocaMap.end()) break; // VLAs.
     int FI = SI->second;
-    if (MMI) {
-      if (MDNode *Dbg = DI->getMetadata("dbg"))
-        MMI->setVariableDbgInfo(DI->getVariable(), FI, Dbg);
-    }
+    if (MDNode *Dbg = DI->getDbgMetadata())
+      MMI->setVariableDbgInfo(DI->getVariable(), FI, Dbg);
+    
     // Building the map above is target independent.  Generating DBG_VALUE
     // inline is target dependent; do this now.
     (void)TargetSelectInstruction(cast<Instruction>(I));