[clang] [LifetimeSafety] Implement multi-level origins (PR #168344)

[Yitzhak Mandelbaum via cfe-commits]

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@@ -186,13 +286,32 @@ void FactsGenerator::VisitConditionalOperator(const ConditionalOperator *CO) {
 void FactsGenerator::VisitCXXOperatorCallExpr(const CXXOperatorCallExpr *OCE) {
   // Assignment operators have special "kill-then-propagate" semantics
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ymand wrote:

We should document somewhere that we assume assignment semantics of all user-defined assignment operators.

https://github.com/llvm/llvm-project/pull/168344