[clang] [clang][StaticAnalyzer] Fix crash in SimpleSValBuilder with unsigned __int128 and negative literals (PR #150225)

[via cfe-commits]

github-actions[bot] wrote:

<!--LLVM CODE FORMAT COMMENT: {clang-format}-->


:warning: C/C++ code formatter, clang-format found issues in your code. :warning:

<details>
<summary>
You can test this locally with the following command:
</summary>

``````````bash
git-clang-format --diff HEAD~1 HEAD --extensions cpp,c -- clang/lib/StaticAnalyzer/Checkers/BuiltinFunctionChecker.cpp clang/lib/StaticAnalyzer/Core/BasicValueFactory.cpp clang/lib/StaticAnalyzer/Core/SimpleSValBuilder.cpp clang/test/Analysis/builtin_overflow.c
``````````

</details>

<details>
<summary>
View the diff from clang-format here.
</summary>

``````````diff
diff --git a/clang/lib/StaticAnalyzer/Core/BasicValueFactory.cpp b/clang/lib/StaticAnalyzer/Core/BasicValueFactory.cpp
index e0001acdf..8afb3f340 100644
--- a/clang/lib/StaticAnalyzer/Core/BasicValueFactory.cpp
+++ b/clang/lib/StaticAnalyzer/Core/BasicValueFactory.cpp
@@ -254,13 +254,14 @@ BasicValueFactory::evalAPSInt(BinaryOperator::Opcode Op, const llvm::APSInt &V1,
       if (V1.getBitWidth() >= 128 || V2.getBitWidth() >= 128) {
         // If either operand is zero, result is zero
         if (V1 == 0 || V2 == 0) {
-          return getValue(llvm::APSInt(llvm::APInt::getZero(std::max(V1.getBitWidth(), V2.getBitWidth())),
+          return getValue(llvm::APSInt(llvm::APInt::getZero(std::max(
+                                           V1.getBitWidth(), V2.getBitWidth())),
                                        V1.isUnsigned() && V2.isUnsigned()));
         }
 
-        // For __int128 types, be conservative to avoid crashes in APInt multiplication
-        // This happens when multiplying unsigned __int128 with large values (like negative
-        // numbers converted to unsigned)
+        // For __int128 types, be conservative to avoid crashes in APInt
+        // multiplication This happens when multiplying unsigned __int128 with
+        // large values (like negative numbers converted to unsigned)
         return std::nullopt;
       }
       return getValue(V1 * V2);
diff --git a/clang/lib/StaticAnalyzer/Core/SimpleSValBuilder.cpp b/clang/lib/StaticAnalyzer/Core/SimpleSValBuilder.cpp
index 29a711c81..60a8eed51 100644
--- a/clang/lib/StaticAnalyzer/Core/SimpleSValBuilder.cpp
+++ b/clang/lib/StaticAnalyzer/Core/SimpleSValBuilder.cpp
@@ -223,17 +223,17 @@ SVal SimpleSValBuilder::MakeSymIntVal(const SymExpr *LHS,
     } else {
       APSIntType resultIntTy = BasicVals.getAPSIntType(resultTy);
       if (isNegationValuePreserving(RHS, resultIntTy)) {
-      // For large unsigned types, we need to be careful about the conversion
-      // to avoid issues with very large intermediate values
-      if (resultIntTy.isUnsigned() && resultIntTy.getBitWidth() > 64) {
-        // For large unsigned types, convert the absolute value directly
-        // instead of converting the negative value and then negating
-        llvm::APSInt AbsRHS = RHS;
-        AbsRHS.negate();
-        ConvertedRHS = BasicVals.Convert(resultTy, AbsRHS);
-      } else {
-        ConvertedRHS = BasicVals.getValue(-resultIntTy.convert(RHS));
-      }
+        // For large unsigned types, we need to be careful about the conversion
+        // to avoid issues with very large intermediate values
+        if (resultIntTy.isUnsigned() && resultIntTy.getBitWidth() > 64) {
+          // For large unsigned types, convert the absolute value directly
+          // instead of converting the negative value and then negating
+          llvm::APSInt AbsRHS = RHS;
+          AbsRHS.negate();
+          ConvertedRHS = BasicVals.Convert(resultTy, AbsRHS);
+        } else {
+          ConvertedRHS = BasicVals.getValue(-resultIntTy.convert(RHS));
+        }
         op = (op == BO_Add) ? BO_Sub : BO_Add;
       } else {
         ConvertedRHS = BasicVals.Convert(resultTy, RHS);

``````````

</details>


https://github.com/llvm/llvm-project/pull/150225