Debug Info: clean up usage of Verify.

No functionality change.
It should suffice to check the type of a debug info metadata, instead of
calling Verify. For cases where we know the type of a DI metadata, use
assert.

Also update testing cases to make them conform to the format of DI classes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185135 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp b/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
index 2fb7664..4309dc1 100644
--- a/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
+++ b/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
@@ -112,8 +112,11 @@
       // in a predictable order.
       if (const DbgDeclareInst *DI = dyn_cast<DbgDeclareInst>(I)) {
         MachineModuleInfo &MMI = MF->getMMI();
+        DIVariable DIVar(DI->getVariable());
+        assert((!DIVar || DIVar.isVariable()) &&
+          "Variable in DbgDeclareInst should be either null or a DIVariable.");
         if (MMI.hasDebugInfo() &&
-            DIVariable(DI->getVariable()).Verify() &&
+            DIVar &&
             !DI->getDebugLoc().isUnknown()) {
           // Don't handle byval struct arguments or VLAs, for example.
           // Non-byval arguments are handled here (they refer to the stack