fix compile

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100760 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/CBackend/CBackend.cpp b/lib/Target/CBackend/CBackend.cpp
index 0d0af46..c87fadb 100644
--- a/lib/Target/CBackend/CBackend.cpp
+++ b/lib/Target/CBackend/CBackend.cpp
@@ -274,8 +274,8 @@
     
     // isInlineAsm - Check if the instruction is a call to an inline asm chunk
     static bool isInlineAsm(const Instruction& I) {
-      if (isa<CallInst>(&I) && isa<InlineAsm>(I.getCalledValue()))
-        return true;
+      if (const CallInst *CI = dyn_cast<CallInst>(&I))
+        return isa<InlineAsm>(CI->getCalledValue());
       return false;
     }