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diff --git a/contrib/llvm-project/llvm/lib/Transforms/ObjCARC/DependencyAnalysis.h b/contrib/llvm-project/llvm/lib/Transforms/ObjCARC/DependencyAnalysis.h
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+++ b/contrib/llvm-project/llvm/lib/Transforms/ObjCARC/DependencyAnalysis.h
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+//===- DependencyAnalysis.h - ObjC ARC Optimization ---*- 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
+//
+//===----------------------------------------------------------------------===//
+/// \file
+///
+/// This file declares special dependency analysis routines used in Objective C
+/// ARC Optimizations.
+///
+/// WARNING: This file knows about certain library functions. It recognizes them
+/// by name, and hardwires knowledge of their semantics.
+///
+/// WARNING: This file knows about how certain Objective-C library functions are
+/// used. Naive LLVM IR transformations which would otherwise be
+/// behavior-preserving may break these assumptions.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_TRANSFORMS_OBJCARC_DEPENDENCYANALYSIS_H
+#define LLVM_LIB_TRANSFORMS_OBJCARC_DEPENDENCYANALYSIS_H
+
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/Analysis/ObjCARCInstKind.h"
+
+namespace llvm {
+  class BasicBlock;
+  class Instruction;
+  class Value;
+}
+
+namespace llvm {
+namespace objcarc {
+
+class ProvenanceAnalysis;
+
+/// \enum DependenceKind
+/// Defines different dependence kinds among various ARC constructs.
+///
+/// There are several kinds of dependence-like concepts in use here.
+///
+enum DependenceKind {
+  NeedsPositiveRetainCount,
+  AutoreleasePoolBoundary,
+  CanChangeRetainCount,
+  RetainAutoreleaseDep,       ///< Blocks objc_retainAutorelease.
+  RetainAutoreleaseRVDep,     ///< Blocks objc_retainAutoreleaseReturnValue.
+  RetainRVDep                 ///< Blocks objc_retainAutoreleasedReturnValue.
+};
+
+/// Find dependent instructions. If there is exactly one dependent instruction,
+/// return it. Otherwise, return null.
+llvm::Instruction *findSingleDependency(DependenceKind Flavor, const Value *Arg,
+                                        BasicBlock *StartBB,
+                                        Instruction *StartInst,
+                                        ProvenanceAnalysis &PA);
+
+bool
+Depends(DependenceKind Flavor, Instruction *Inst, const Value *Arg,
+        ProvenanceAnalysis &PA);
+
+/// Test whether the given instruction can "use" the given pointer's object in a
+/// way that requires the reference count to be positive.
+bool CanUse(const Instruction *Inst, const Value *Ptr, ProvenanceAnalysis &PA,
+            ARCInstKind Class);
+
+/// Test whether the given instruction can result in a reference count
+/// modification (positive or negative) for the pointer's object.
+bool CanAlterRefCount(const Instruction *Inst, const Value *Ptr,
+                      ProvenanceAnalysis &PA, ARCInstKind Class);
+
+/// Returns true if we can not conservatively prove that Inst can not decrement
+/// the reference count of Ptr. Returns false if we can.
+bool CanDecrementRefCount(const Instruction *Inst, const Value *Ptr,
+                          ProvenanceAnalysis &PA, ARCInstKind Class);
+
+static inline bool CanDecrementRefCount(const Instruction *Inst,
+                                        const Value *Ptr,
+                                        ProvenanceAnalysis &PA) {
+  return CanDecrementRefCount(Inst, Ptr, PA, GetARCInstKind(Inst));
+}
+
+} // namespace objcarc
+} // namespace llvm
+
+#endif