[clang] [analyzer] Fix a crash from element region construction during `ArrayInitLoopExpr` analysis (PR #113570)

[Balazs Benics via cfe-commits]

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@@ -513,70 +513,25 @@ ProgramStateRef ExprEngine::updateObjectsUnderConstruction(
 static ProgramStateRef
 bindRequiredArrayElementToEnvironment(ProgramStateRef State,
                                       const ArrayInitLoopExpr *AILE,
-                                      const LocationContext *LCtx, SVal Idx) {
-  // The ctor in this case is guaranteed to be a copy ctor, otherwise we hit a
-  // compile time error.
-  //
-  //  -ArrayInitLoopExpr                <-- we're here
-  //   |-OpaqueValueExpr
-  //   | `-DeclRefExpr                  <-- match this
-  //   `-CXXConstructExpr
-  //     `-ImplicitCastExpr
-  //       `-ArraySubscriptExpr
-  //         |-ImplicitCastExpr
-  //         | `-OpaqueValueExpr
-  //         |   `-DeclRefExpr
-  //         `-ArrayInitIndexExpr
-  //
-  // The resulting expression might look like the one below in an implicit
-  // copy/move ctor.
-  //
-  //   ArrayInitLoopExpr                <-- we're here
-  //   |-OpaqueValueExpr
-  //   | `-MemberExpr                   <-- match this
-  //   |  (`-CXXStaticCastExpr)         <-- move ctor only
-  //   |     `-DeclRefExpr
-  //   `-CXXConstructExpr
-  //     `-ArraySubscriptExpr
-  //       |-ImplicitCastExpr
-  //       | `-OpaqueValueExpr
-  //       |   `-MemberExpr
-  //       |     `-DeclRefExpr
-  //       `-ArrayInitIndexExpr
-  //
-  // The resulting expression for a multidimensional array.
-  // ArrayInitLoopExpr                  <-- we're here
-  // |-OpaqueValueExpr
-  // | `-DeclRefExpr                    <-- match this
-  // `-ArrayInitLoopExpr
-  //   |-OpaqueValueExpr
-  //   | `-ArraySubscriptExpr
-  //   |   |-ImplicitCastExpr
-  //   |   | `-OpaqueValueExpr
-  //   |   |   `-DeclRefExpr
-  //   |   `-ArrayInitIndexExpr
-  //   `-CXXConstructExpr             <-- extract this
-  //     ` ...
-
-  const auto *OVESrc = AILE->getCommonExpr()->getSourceExpr();
+                                      const LocationContext *LCtx, NonLoc Idx) {
+  SValBuilder &SVB = State->getStateManager().getSValBuilder();
+  MemRegionManager &MRMgr = SVB.getRegionManager();
+  ASTContext &Ctx = SVB.getContext();
 
   // HACK: There is no way we can put the index of the array element into the
   // CFG unless we unroll the loop, so we manually select and bind the required
   // parameter to the environment.
-  const auto *CE =
+  const Expr *SourceArray = AILE->getCommonExpr()->getSourceExpr();
+  const auto *Ctor =
       cast<CXXConstructExpr>(extractElementInitializerFromNestedAILE(AILE));
 
-  SVal Base = UnknownVal();
-  if (const auto *ME = dyn_cast<MemberExpr>(OVESrc))
-    Base = State->getSVal(ME, LCtx);
-  else if (const auto *DRE = dyn_cast<DeclRefExpr>(OVESrc))
-    Base = State->getLValue(cast<VarDecl>(DRE->getDecl()), LCtx);
-  else
-    llvm_unreachable("ArrayInitLoopExpr contains unexpected source expression");
-
-  SVal NthElem = State->getLValue(CE->getType(), Idx, Base);
+  const SubRegion *SourceArrayRegion =
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steakhal wrote:

Use const auto here as the type is already spelled in the statement.

https://github.com/llvm/llvm-project/pull/113570