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diff --git a/clang-r344140b/include/llvm/Analysis/MustExecute.h b/clang-r344140b/include/llvm/Analysis/MustExecute.h
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+//===- MustExecute.h - Is an instruction known to execute--------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+/// \file
+/// Contains a collection of routines for determining if a given instruction is
+/// guaranteed to execute if a given point in control flow is reached.  The most
+/// common example is an instruction within a loop being provably executed if we
+/// branch to the header of it's containing loop.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ANALYSIS_MUSTEXECUTE_H
+#define LLVM_ANALYSIS_MUSTEXECUTE_H
+
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/Analysis/EHPersonalities.h"
+#include "llvm/Analysis/LoopInfo.h"
+#include "llvm/IR/BasicBlock.h"
+#include "llvm/IR/Dominators.h"
+#include "llvm/IR/Instruction.h"
+
+namespace llvm {
+
+class Instruction;
+class DominatorTree;
+class Loop;
+
+/// Captures loop safety information.
+/// It keep information for loop blocks may throw exception or otherwise
+/// exit abnormaly on any iteration of the loop which might actually execute
+/// at runtime.  The primary way to consume this infromation is via
+/// isGuaranteedToExecute below, but some callers bailout or fallback to
+/// alternate reasoning if a loop contains any implicit control flow.
+/// NOTE: LoopSafetyInfo contains cached information regarding loops and their
+/// particular blocks. This information is only dropped on invocation of
+/// computeLoopSafetyInfo. If the loop or any of its block is deleted, or if
+/// any thrower instructions have been added or removed from them, or if the
+/// control flow has changed, or in case of other meaningful modifications, the
+/// LoopSafetyInfo needs to be recomputed. If a meaningful modifications to the
+/// loop were made and the info wasn't recomputed properly, the behavior of all
+/// methods except for computeLoopSafetyInfo is undefined.
+class LoopSafetyInfo {
+  bool MayThrow = false;       // The current loop contains an instruction which
+                               // may throw.
+  bool HeaderMayThrow = false; // Same as previous, but specific to loop header
+
+  /// Collect all blocks from \p CurLoop which lie on all possible paths from
+  /// the header of \p CurLoop (inclusive) to BB (exclusive) into the set
+  /// \p Predecessors. If \p BB is the header, \p Predecessors will be empty.
+  void collectTransitivePredecessors(
+      const Loop *CurLoop, const BasicBlock *BB,
+      SmallPtrSetImpl<const BasicBlock *> &Predecessors) const;
+
+public:
+  // Used to update funclet bundle operands.
+  DenseMap<BasicBlock *, ColorVector> BlockColors;
+
+  /// Returns true iff the header block of the loop for which this info is
+  /// calculated contains an instruction that may throw or otherwise exit
+  /// abnormally.
+  bool headerMayThrow() const;
+
+  /// Returns true iff any block of the loop for which this info is contains an
+  /// instruction that may throw or otherwise exit abnormally.
+  bool anyBlockMayThrow() const;
+
+  /// Return true if we must reach the block \p BB under assumption that the
+  /// loop \p CurLoop is entered and no instruction throws or otherwise exits
+  /// abnormally.
+  bool allLoopPathsLeadToBlock(const Loop *CurLoop, const BasicBlock *BB,
+                               const DominatorTree *DT) const;
+
+  /// Computes safety information for a loop checks loop body & header for
+  /// the possibility of may throw exception, it takes LoopSafetyInfo and loop
+  /// as argument. Updates safety information in LoopSafetyInfo argument.
+  /// Note: This is defined to clear and reinitialize an already initialized
+  /// LoopSafetyInfo.  Some callers rely on this fact.
+  void computeLoopSafetyInfo(Loop *);
+
+  LoopSafetyInfo() = default;
+};
+
+/// Returns true if the instruction in a loop is guaranteed to execute at least
+/// once (under the assumption that the loop is entered).
+bool isGuaranteedToExecute(const Instruction &Inst, const DominatorTree *DT,
+                           const Loop *CurLoop,
+                           const LoopSafetyInfo *SafetyInfo);
+
+}
+
+#endif