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diff --git a/clang-r353983/include/llvm/Analysis/CmpInstAnalysis.h b/clang-r353983/include/llvm/Analysis/CmpInstAnalysis.h
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+//===-- CmpInstAnalysis.h - Utils to help fold compare insts ----*- 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 holds routines to help analyse compare instructions
+// and fold them into constants or other compare instructions
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ANALYSIS_CMPINSTANALYSIS_H
+#define LLVM_ANALYSIS_CMPINSTANALYSIS_H
+
+#include "llvm/IR/InstrTypes.h"
+
+namespace llvm {
+  class ICmpInst;
+  class Value;
+
+  /// Encode a icmp predicate into a three bit mask. These bits are carefully
+  /// arranged to allow folding of expressions such as:
+  ///
+  ///      (A < B) | (A > B) --> (A != B)
+  ///
+  /// Note that this is only valid if the first and second predicates have the
+  /// same sign. It is illegal to do: (A u< B) | (A s> B)
+  ///
+  /// Three bits are used to represent the condition, as follows:
+  ///   0  A > B
+  ///   1  A == B
+  ///   2  A < B
+  ///
+  /// <=>  Value  Definition
+  /// 000     0   Always false
+  /// 001     1   A >  B
+  /// 010     2   A == B
+  /// 011     3   A >= B
+  /// 100     4   A <  B
+  /// 101     5   A != B
+  /// 110     6   A <= B
+  /// 111     7   Always true
+  ///
+  unsigned getICmpCode(const ICmpInst *ICI, bool InvertPred = false);
+
+  /// This is the complement of getICmpCode. It turns a predicate code into
+  /// either a constant true or false or the predicate for a new ICmp.
+  /// The sign is passed in to determine which kind of predicate to use in the
+  /// new ICmp instruction.
+  /// Non-NULL return value will be a true or false constant.
+  /// NULL return means a new ICmp is needed. The predicate is output in Pred.
+  Constant *getPredForICmpCode(unsigned Code, bool Sign, Type *OpTy,
+                               CmpInst::Predicate &Pred);
+
+  /// Return true if both predicates match sign or if at least one of them is an
+  /// equality comparison (which is signless).
+  bool predicatesFoldable(CmpInst::Predicate P1, CmpInst::Predicate P2);
+
+  /// Decompose an icmp into the form ((X & Mask) pred 0) if possible. The
+  /// returned predicate is either == or !=. Returns false if decomposition
+  /// fails.
+  bool decomposeBitTestICmp(Value *LHS, Value *RHS, CmpInst::Predicate &Pred,
+                            Value *&X, APInt &Mask,
+                            bool LookThroughTrunc = true);
+
+} // end namespace llvm
+
+#endif