[clang] [llvm] [analyzer] Fix _BitInt support & casting behavior for Z3 symbolic execution (PR #210525)

[via cfe-commits]

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@@ -750,10 +729,8 @@ void ExprEngine::VisitLogicalExpr(const BinaryOperator* B, ExplodedNode *Pred,
       // We evaluate "RHSVal != 0" expression which result in 0 if the value is
       // known to be false, 1 if the value is known to be true and a new symbol
       // when the assumption is unknown.
-      nonloc::ConcreteInt Zero(getBasicVals().getValue(0, B->getType()));
-      X = evalBinOp(N->getState(), BO_NE,
-                    svalBuilder.evalCast(RHSVal, B->getType(), RHS->getType()),
-                    Zero, B->getType());
+      X = evalBinOp(N->getState(), BO_NE, RHSVal,
+                    svalBuilder.makeZeroVal(RHS->getType()), B->getType());
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rdevshp wrote:

I dropped the cast because it incorrectly truncated RHSVal and caused the test to say `FALSE` for the Z3 solver. I have added the test for the normal range solver.

https://github.com/llvm/llvm-project/pull/210525