[LVI] Make a precondition explicit rather than handling a case which never happens [NFC]

llvm-svn: 267481
diff --git a/llvm/lib/Analysis/LazyValueInfo.cpp b/llvm/lib/Analysis/LazyValueInfo.cpp
index 98136b8..66b64c5 100644
--- a/llvm/lib/Analysis/LazyValueInfo.cpp
+++ b/llvm/lib/Analysis/LazyValueInfo.cpp
@@ -1116,7 +1116,8 @@
 
 bool getValueFromFromCondition(Value *Val, ICmpInst *ICI,
                                LVILatticeVal &Result, bool isTrueDest) {
-  if (ICI && isa<Constant>(ICI->getOperand(1))) {
+  assert(ICI && "precondition");
+  if (isa<Constant>(ICI->getOperand(1))) {
     if (ICI->isEquality() && ICI->getOperand(0) == Val) {
       // We know that V has the RHS constant if this is a true SETEQ or
       // false SETNE.