[TableGen] Replace a dyn_cast with isa to avoid an unused variable warning introduced in r355785. NFC

llvm-svn: 355837

1 files changed, 2 insertions, 6 deletions

diff --git a/llvm/utils/TableGen/DAGISelMatcher.cpp b/llvm/utils/TableGen/DAGISelMatcher.cpp
index b2d819cae9e..bebd205ad58 100644
--- a/llvm/utils/TableGen/DAGISelMatcher.cpp
+++ b/llvm/utils/TableGen/DAGISelMatcher.cpp
@@ -414,14 +414,10 @@ bool CheckValueTypeMatcher::isContradictoryImpl(const Matcher *M) const {
 
 bool CheckImmAllOnesVMatcher::isContradictoryImpl(const Matcher *M) const {
   // AllZeros is contradictory.
-  if (const auto *CIAZVM = dyn_cast<CheckImmAllZerosVMatcher>(M))
-    return true;
-  return false;
+  return isa<CheckImmAllZerosVMatcher>(M);
 }
 
 bool CheckImmAllZerosVMatcher::isContradictoryImpl(const Matcher *M) const {
   // AllOnes is contradictory.
-  if (const auto *CIAOVM = dyn_cast<CheckImmAllOnesVMatcher>(M))
-    return true;
-  return false;
+  return isa<CheckImmAllOnesVMatcher>(M);
 }