[clang] [clang][CFG] Fix assertion failure in checkIncorrectLogicOperator (PR #142897)

[Ziqing Luo via cfe-commits]

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@@ -1261,6 +1261,28 @@ class CFGBuilder {
         L2Result.Val.getKind() == APValue::Float) {
       llvm::APFloat L1 = L1Result.Val.getFloat();
       llvm::APFloat L2 = L2Result.Val.getFloat();
+      // Note that L1 and L2 do not necessarily have the same type.  For example
+      // `x != 0 || x != 1.0`, if `x` is a float16, the two literals `0` and
+      // `1.0` are float16 and double respectively.  In this case, we should do
+      // a conversion before comparing L1 and L2.  Their types must be
+      // compatible since they are comparing with the same DRE.
+      int8_t Order = Context->getFloatingTypeOrder(NumExpr1->getType(),
+                                                   NumExpr2->getType());
+      bool convertLoseInfo = false;
+
+      if (Order > 0) {
+        // type rank L1 > L2:
+        if (L2.convert(L1.getSemantics(), llvm::APFloat::rmNearestTiesToEven,
+                       &convertLoseInfo))
+          return {};
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ziqingluo-90 wrote:

This branch is for failed conversions, so it no longer matters whether it loses info.

https://github.com/llvm/llvm-project/pull/142897