[clang] [NFC][LifetimeSafety]: Track assignment history within a single CFGBlock (PR #196075)

[Utkarsh Saxena via cfe-commits]

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@@ -0,0 +1,33 @@
+//====- OriginFlowChain.h - C++ Lifetime Safety Checker --------*- C++ -*-====//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines buildOriginFlowChain, which is used to build the
+// propagation flow of a given Loan within a specified Origin, starting
+// from a particular ProgramPoint.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_ANALYSIS_ANALYSES_LIFETIMESAFETY_ORIGINFLOWCHAIN_H
+#define LLVM_CLANG_ANALYSIS_ANALYSES_LIFETIMESAFETY_ORIGINFLOWCHAIN_H
+
+#include "clang/Analysis/Analyses/LifetimeSafety/Facts.h"
+#include "clang/Analysis/Analyses/LifetimeSafety/LoanPropagation.h"
+
+namespace clang::lifetimes::internal {
+
+/// Builds a chain of origin flows for a specific loan. It tracks how the Loan
+/// moves and transforms.
+///
+/// This function starts from a given ProgramPoint and builds the propagation
+/// flow of the specified LoanID within the context of a given OriginID.
+llvm::SmallVector<OriginID> buildOriginFlowChain(
+    const FactManager &FactMgr, const LoanPropagationAnalysis &LoanPropagation,
+    ProgramPoint StartPoint, const OriginID StartOID, const LoanID TargetLoan);
+} // namespace clang::lifetimes::internal
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usx95 wrote:

The API looks good to me. Now that it is simplified, I wonder if this can be moved to `LoanPropagationAnalysis` instead of having this in a separate file.

https://github.com/llvm/llvm-project/pull/196075