[llvm] r299120 - [InstSimplify] Use APInt::isMaxSignedValue() instead of comparing with ~APInt::getSignBit. NFC

[Craig Topper via llvm-commits]

Author: ctopper
Date: Thu Mar 30 17:10:54 2017
New Revision: 299120

URL: http://llvm.org/viewvc/llvm-project?rev=299120&view=rev
Log:
[InstSimplify] Use APInt::isMaxSignedValue() instead of comparing with ~APInt::getSignBit. NFC

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

Modified: llvm/trunk/lib/Analysis/InstructionSimplify.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/InstructionSimplify.cpp?rev=299120&r1=299119&r2=299120&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/InstructionSimplify.cpp (original)
+++ llvm/trunk/lib/Analysis/InstructionSimplify.cpp Thu Mar 30 17:10:54 2017
@@ -703,7 +703,7 @@ static Value *SimplifySubInst(Value *Op0
     APInt KnownZero(BitWidth, 0);
     APInt KnownOne(BitWidth, 0);
     computeKnownBits(Op1, KnownZero, KnownOne, Q.DL, 0, Q.AC, Q.CxtI, Q.DT);
-    if (KnownZero == ~APInt::getSignBit(BitWidth)) {
+    if (KnownZero.isMaxSignedValue()) {
       // Op1 is either 0 or the minimum signed value. If the sub is NSW, then
       // Op1 must be 0 because negating the minimum signed value is undefined.
       if (isNSW)