[llvm] r176537 - Use dyn_cast instead of isa && cast. No functionality change.

[Jakub Staszak]

Author: kuba
Date: Tue Mar  5 18:16:16 2013
New Revision: 176537

URL: http://llvm.org/viewvc/llvm-project?rev=176537&view=rev
Log:
Use dyn_cast instead of isa && cast. No functionality change.

Modified:
    llvm/trunk/lib/Analysis/ValueTracking.cpp

Modified: llvm/trunk/lib/Analysis/ValueTracking.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/ValueTracking.cpp?rev=176537&r1=176536&r2=176537&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/ValueTracking.cpp (original)
+++ llvm/trunk/lib/Analysis/ValueTracking.cpp Tue Mar  5 18:16:16 2013
@@ -1396,10 +1396,10 @@ bool llvm::CannotBeNegativeZero(const Va
       return true;
 
   // (add x, 0.0) is guaranteed to return +0.0, not -0.0.
-  if (I->getOpcode() == Instruction::FAdd &&
-      isa<ConstantFP>(I->getOperand(1)) &&
-      cast<ConstantFP>(I->getOperand(1))->isNullValue())
-    return true;
+  if (I->getOpcode() == Instruction::FAdd)
+    if (ConstantFP *CFP = dyn_cast<ConstantFP>(I->getOperand(1)))
+      if (CFP->isNullValue())
+        return true;
 
   // sitofp and uitofp turn into +0.0 for zero.
   if (isa<SIToFPInst>(I) || isa<UIToFPInst>(I))