CodeGen: Stop using DIDescriptor::is*() and auto-casting

Same as r234255, but for lib/CodeGen and lib/Target.

llvm-svn: 234258
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index fdfdd15..9080e34 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -5902,7 +5902,7 @@
 SDDbgValue *SelectionDAG::getDbgValue(MDNode *Var, MDNode *Expr, SDNode *N,
                                       unsigned R, bool IsIndirect, uint64_t Off,
                                       DebugLoc DL, unsigned O) {
-  assert(DIVariable(Var)->isValidLocationForIntrinsic(DL) &&
+  assert(cast<MDLocalVariable>(Var)->isValidLocationForIntrinsic(DL) &&
          "Expected inlined-at fields to agree");
   return new (Allocator) SDDbgValue(Var, Expr, N, R, IsIndirect, Off, DL, O);
 }
@@ -5911,7 +5911,7 @@
 SDDbgValue *SelectionDAG::getConstantDbgValue(MDNode *Var, MDNode *Expr,
                                               const Value *C, uint64_t Off,
                                               DebugLoc DL, unsigned O) {
-  assert(DIVariable(Var)->isValidLocationForIntrinsic(DL) &&
+  assert(cast<MDLocalVariable>(Var)->isValidLocationForIntrinsic(DL) &&
          "Expected inlined-at fields to agree");
   return new (Allocator) SDDbgValue(Var, Expr, C, Off, DL, O);
 }
@@ -5920,7 +5920,7 @@
 SDDbgValue *SelectionDAG::getFrameIndexDbgValue(MDNode *Var, MDNode *Expr,
                                                 unsigned FI, uint64_t Off,
                                                 DebugLoc DL, unsigned O) {
-  assert(DIVariable(Var)->isValidLocationForIntrinsic(DL) &&
+  assert(cast<MDLocalVariable>(Var)->isValidLocationForIntrinsic(DL) &&
          "Expected inlined-at fields to agree");
   return new (Allocator) SDDbgValue(Var, Expr, FI, Off, DL, O);
 }