Update clang to r339409b.

Change-Id: Ied8a188bb072c40035320acedc86164b66d920af
diff --git a/linux-x64/clang/include/llvm/Analysis/IVDescriptors.h b/linux-x64/clang/include/llvm/Analysis/IVDescriptors.h
new file mode 100644
index 0000000..d1d7e5e
--- /dev/null
+++ b/linux-x64/clang/include/llvm/Analysis/IVDescriptors.h
@@ -0,0 +1,352 @@
+//===- llvm/Analysis/IVDescriptors.h - IndVar Descriptors -------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file "describes" induction and recurrence variables.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ANALYSIS_IVDESCRIPTORS_H
+#define LLVM_ANALYSIS_IVDESCRIPTORS_H
+
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/Optional.h"
+#include "llvm/ADT/SetVector.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Analysis/DemandedBits.h"
+#include "llvm/Analysis/EHPersonalities.h"
+#include "llvm/Analysis/MustExecute.h"
+#include "llvm/Analysis/TargetTransformInfo.h"
+#include "llvm/IR/Dominators.h"
+#include "llvm/IR/IRBuilder.h"
+#include "llvm/IR/InstrTypes.h"
+#include "llvm/IR/Operator.h"
+#include "llvm/IR/ValueHandle.h"
+#include "llvm/Support/Casting.h"
+
+namespace llvm {
+
+class AliasSet;
+class AliasSetTracker;
+class BasicBlock;
+class DataLayout;
+class Loop;
+class LoopInfo;
+class OptimizationRemarkEmitter;
+class PredicatedScalarEvolution;
+class PredIteratorCache;
+class ScalarEvolution;
+class SCEV;
+class TargetLibraryInfo;
+class TargetTransformInfo;
+
+/// The RecurrenceDescriptor is used to identify recurrences variables in a
+/// loop. Reduction is a special case of recurrence that has uses of the
+/// recurrence variable outside the loop. The method isReductionPHI identifies
+/// reductions that are basic recurrences.
+///
+/// Basic recurrences are defined as the summation, product, OR, AND, XOR, min,
+/// or max of a set of terms. For example: for(i=0; i<n; i++) { total +=
+/// array[i]; } is a summation of array elements. Basic recurrences are a
+/// special case of chains of recurrences (CR). See ScalarEvolution for CR
+/// references.
+
+/// This struct holds information about recurrence variables.
+class RecurrenceDescriptor {
+public:
+  /// This enum represents the kinds of recurrences that we support.
+  enum RecurrenceKind {
+    RK_NoRecurrence,  ///< Not a recurrence.
+    RK_IntegerAdd,    ///< Sum of integers.
+    RK_IntegerMult,   ///< Product of integers.
+    RK_IntegerOr,     ///< Bitwise or logical OR of numbers.
+    RK_IntegerAnd,    ///< Bitwise or logical AND of numbers.
+    RK_IntegerXor,    ///< Bitwise or logical XOR of numbers.
+    RK_IntegerMinMax, ///< Min/max implemented in terms of select(cmp()).
+    RK_FloatAdd,      ///< Sum of floats.
+    RK_FloatMult,     ///< Product of floats.
+    RK_FloatMinMax    ///< Min/max implemented in terms of select(cmp()).
+  };
+
+  // This enum represents the kind of minmax recurrence.
+  enum MinMaxRecurrenceKind {
+    MRK_Invalid,
+    MRK_UIntMin,
+    MRK_UIntMax,
+    MRK_SIntMin,
+    MRK_SIntMax,
+    MRK_FloatMin,
+    MRK_FloatMax
+  };
+
+  RecurrenceDescriptor() = default;
+
+  RecurrenceDescriptor(Value *Start, Instruction *Exit, RecurrenceKind K,
+                       MinMaxRecurrenceKind MK, Instruction *UAI, Type *RT,
+                       bool Signed, SmallPtrSetImpl<Instruction *> &CI)
+      : StartValue(Start), LoopExitInstr(Exit), Kind(K), MinMaxKind(MK),
+        UnsafeAlgebraInst(UAI), RecurrenceType(RT), IsSigned(Signed) {
+    CastInsts.insert(CI.begin(), CI.end());
+  }
+
+  /// This POD struct holds information about a potential recurrence operation.
+  class InstDesc {
+  public:
+    InstDesc(bool IsRecur, Instruction *I, Instruction *UAI = nullptr)
+        : IsRecurrence(IsRecur), PatternLastInst(I), MinMaxKind(MRK_Invalid),
+          UnsafeAlgebraInst(UAI) {}
+
+    InstDesc(Instruction *I, MinMaxRecurrenceKind K, Instruction *UAI = nullptr)
+        : IsRecurrence(true), PatternLastInst(I), MinMaxKind(K),
+          UnsafeAlgebraInst(UAI) {}
+
+    bool isRecurrence() { return IsRecurrence; }
+
+    bool hasUnsafeAlgebra() { return UnsafeAlgebraInst != nullptr; }
+
+    Instruction *getUnsafeAlgebraInst() { return UnsafeAlgebraInst; }
+
+    MinMaxRecurrenceKind getMinMaxKind() { return MinMaxKind; }
+
+    Instruction *getPatternInst() { return PatternLastInst; }
+
+  private:
+    // Is this instruction a recurrence candidate.
+    bool IsRecurrence;
+    // The last instruction in a min/max pattern (select of the select(icmp())
+    // pattern), or the current recurrence instruction otherwise.
+    Instruction *PatternLastInst;
+    // If this is a min/max pattern the comparison predicate.
+    MinMaxRecurrenceKind MinMaxKind;
+    // Recurrence has unsafe algebra.
+    Instruction *UnsafeAlgebraInst;
+  };
+
+  /// Returns a struct describing if the instruction 'I' can be a recurrence
+  /// variable of type 'Kind'. If the recurrence is a min/max pattern of
+  /// select(icmp()) this function advances the instruction pointer 'I' from the
+  /// compare instruction to the select instruction and stores this pointer in
+  /// 'PatternLastInst' member of the returned struct.
+  static InstDesc isRecurrenceInstr(Instruction *I, RecurrenceKind Kind,
+                                    InstDesc &Prev, bool HasFunNoNaNAttr);
+
+  /// Returns true if instruction I has multiple uses in Insts
+  static bool hasMultipleUsesOf(Instruction *I,
+                                SmallPtrSetImpl<Instruction *> &Insts);
+
+  /// Returns true if all uses of the instruction I is within the Set.
+  static bool areAllUsesIn(Instruction *I, SmallPtrSetImpl<Instruction *> &Set);
+
+  /// Returns a struct describing if the instruction if the instruction is a
+  /// Select(ICmp(X, Y), X, Y) instruction pattern corresponding to a min(X, Y)
+  /// or max(X, Y).
+  static InstDesc isMinMaxSelectCmpPattern(Instruction *I, InstDesc &Prev);
+
+  /// Returns identity corresponding to the RecurrenceKind.
+  static Constant *getRecurrenceIdentity(RecurrenceKind K, Type *Tp);
+
+  /// Returns the opcode of binary operation corresponding to the
+  /// RecurrenceKind.
+  static unsigned getRecurrenceBinOp(RecurrenceKind Kind);
+
+  /// Returns true if Phi is a reduction of type Kind and adds it to the
+  /// RecurrenceDescriptor. If either \p DB is non-null or \p AC and \p DT are
+  /// non-null, the minimal bit width needed to compute the reduction will be
+  /// computed.
+  static bool AddReductionVar(PHINode *Phi, RecurrenceKind Kind, Loop *TheLoop,
+                              bool HasFunNoNaNAttr,
+                              RecurrenceDescriptor &RedDes,
+                              DemandedBits *DB = nullptr,
+                              AssumptionCache *AC = nullptr,
+                              DominatorTree *DT = nullptr);
+
+  /// Returns true if Phi is a reduction in TheLoop. The RecurrenceDescriptor
+  /// is returned in RedDes. If either \p DB is non-null or \p AC and \p DT are
+  /// non-null, the minimal bit width needed to compute the reduction will be
+  /// computed.
+  static bool isReductionPHI(PHINode *Phi, Loop *TheLoop,
+                             RecurrenceDescriptor &RedDes,
+                             DemandedBits *DB = nullptr,
+                             AssumptionCache *AC = nullptr,
+                             DominatorTree *DT = nullptr);
+
+  /// Returns true if Phi is a first-order recurrence. A first-order recurrence
+  /// is a non-reduction recurrence relation in which the value of the
+  /// recurrence in the current loop iteration equals a value defined in the
+  /// previous iteration. \p SinkAfter includes pairs of instructions where the
+  /// first will be rescheduled to appear after the second if/when the loop is
+  /// vectorized. It may be augmented with additional pairs if needed in order
+  /// to handle Phi as a first-order recurrence.
+  static bool
+  isFirstOrderRecurrence(PHINode *Phi, Loop *TheLoop,
+                         DenseMap<Instruction *, Instruction *> &SinkAfter,
+                         DominatorTree *DT);
+
+  RecurrenceKind getRecurrenceKind() { return Kind; }
+
+  MinMaxRecurrenceKind getMinMaxRecurrenceKind() { return MinMaxKind; }
+
+  TrackingVH<Value> getRecurrenceStartValue() { return StartValue; }
+
+  Instruction *getLoopExitInstr() { return LoopExitInstr; }
+
+  /// Returns true if the recurrence has unsafe algebra which requires a relaxed
+  /// floating-point model.
+  bool hasUnsafeAlgebra() { return UnsafeAlgebraInst != nullptr; }
+
+  /// Returns first unsafe algebra instruction in the PHI node's use-chain.
+  Instruction *getUnsafeAlgebraInst() { return UnsafeAlgebraInst; }
+
+  /// Returns true if the recurrence kind is an integer kind.
+  static bool isIntegerRecurrenceKind(RecurrenceKind Kind);
+
+  /// Returns true if the recurrence kind is a floating point kind.
+  static bool isFloatingPointRecurrenceKind(RecurrenceKind Kind);
+
+  /// Returns true if the recurrence kind is an arithmetic kind.
+  static bool isArithmeticRecurrenceKind(RecurrenceKind Kind);
+
+  /// Returns the type of the recurrence. This type can be narrower than the
+  /// actual type of the Phi if the recurrence has been type-promoted.
+  Type *getRecurrenceType() { return RecurrenceType; }
+
+  /// Returns a reference to the instructions used for type-promoting the
+  /// recurrence.
+  SmallPtrSet<Instruction *, 8> &getCastInsts() { return CastInsts; }
+
+  /// Returns true if all source operands of the recurrence are SExtInsts.
+  bool isSigned() { return IsSigned; }
+
+private:
+  // The starting value of the recurrence.
+  // It does not have to be zero!
+  TrackingVH<Value> StartValue;
+  // The instruction who's value is used outside the loop.
+  Instruction *LoopExitInstr = nullptr;
+  // The kind of the recurrence.
+  RecurrenceKind Kind = RK_NoRecurrence;
+  // If this a min/max recurrence the kind of recurrence.
+  MinMaxRecurrenceKind MinMaxKind = MRK_Invalid;
+  // First occurrence of unasfe algebra in the PHI's use-chain.
+  Instruction *UnsafeAlgebraInst = nullptr;
+  // The type of the recurrence.
+  Type *RecurrenceType = nullptr;
+  // True if all source operands of the recurrence are SExtInsts.
+  bool IsSigned = false;
+  // Instructions used for type-promoting the recurrence.
+  SmallPtrSet<Instruction *, 8> CastInsts;
+};
+
+/// A struct for saving information about induction variables.
+class InductionDescriptor {
+public:
+  /// This enum represents the kinds of inductions that we support.
+  enum InductionKind {
+    IK_NoInduction,  ///< Not an induction variable.
+    IK_IntInduction, ///< Integer induction variable. Step = C.
+    IK_PtrInduction, ///< Pointer induction var. Step = C / sizeof(elem).
+    IK_FpInduction   ///< Floating point induction variable.
+  };
+
+public:
+  /// Default constructor - creates an invalid induction.
+  InductionDescriptor() = default;
+
+  /// Get the consecutive direction. Returns:
+  ///   0 - unknown or non-consecutive.
+  ///   1 - consecutive and increasing.
+  ///  -1 - consecutive and decreasing.
+  int getConsecutiveDirection() const;
+
+  Value *getStartValue() const { return StartValue; }
+  InductionKind getKind() const { return IK; }
+  const SCEV *getStep() const { return Step; }
+  BinaryOperator *getInductionBinOp() const { return InductionBinOp; }
+  ConstantInt *getConstIntStepValue() const;
+
+  /// Returns true if \p Phi is an induction in the loop \p L. If \p Phi is an
+  /// induction, the induction descriptor \p D will contain the data describing
+  /// this induction. If by some other means the caller has a better SCEV
+  /// expression for \p Phi than the one returned by the ScalarEvolution
+  /// analysis, it can be passed through \p Expr. If the def-use chain
+  /// associated with the phi includes casts (that we know we can ignore
+  /// under proper runtime checks), they are passed through \p CastsToIgnore.
+  static bool
+  isInductionPHI(PHINode *Phi, const Loop *L, ScalarEvolution *SE,
+                 InductionDescriptor &D, const SCEV *Expr = nullptr,
+                 SmallVectorImpl<Instruction *> *CastsToIgnore = nullptr);
+
+  /// Returns true if \p Phi is a floating point induction in the loop \p L.
+  /// If \p Phi is an induction, the induction descriptor \p D will contain
+  /// the data describing this induction.
+  static bool isFPInductionPHI(PHINode *Phi, const Loop *L, ScalarEvolution *SE,
+                               InductionDescriptor &D);
+
+  /// Returns true if \p Phi is a loop \p L induction, in the context associated
+  /// with the run-time predicate of PSE. If \p Assume is true, this can add
+  /// further SCEV predicates to \p PSE in order to prove that \p Phi is an
+  /// induction.
+  /// If \p Phi is an induction, \p D will contain the data describing this
+  /// induction.
+  static bool isInductionPHI(PHINode *Phi, const Loop *L,
+                             PredicatedScalarEvolution &PSE,
+                             InductionDescriptor &D, bool Assume = false);
+
+  /// Returns true if the induction type is FP and the binary operator does
+  /// not have the "fast-math" property. Such operation requires a relaxed FP
+  /// mode.
+  bool hasUnsafeAlgebra() {
+    return InductionBinOp && !cast<FPMathOperator>(InductionBinOp)->isFast();
+  }
+
+  /// Returns induction operator that does not have "fast-math" property
+  /// and requires FP unsafe mode.
+  Instruction *getUnsafeAlgebraInst() {
+    if (!InductionBinOp || cast<FPMathOperator>(InductionBinOp)->isFast())
+      return nullptr;
+    return InductionBinOp;
+  }
+
+  /// Returns binary opcode of the induction operator.
+  Instruction::BinaryOps getInductionOpcode() const {
+    return InductionBinOp ? InductionBinOp->getOpcode()
+                          : Instruction::BinaryOpsEnd;
+  }
+
+  /// Returns a reference to the type cast instructions in the induction
+  /// update chain, that are redundant when guarded with a runtime
+  /// SCEV overflow check.
+  const SmallVectorImpl<Instruction *> &getCastInsts() const {
+    return RedundantCasts;
+  }
+
+private:
+  /// Private constructor - used by \c isInductionPHI.
+  InductionDescriptor(Value *Start, InductionKind K, const SCEV *Step,
+                      BinaryOperator *InductionBinOp = nullptr,
+                      SmallVectorImpl<Instruction *> *Casts = nullptr);
+
+  /// Start value.
+  TrackingVH<Value> StartValue;
+  /// Induction kind.
+  InductionKind IK = IK_NoInduction;
+  /// Step value.
+  const SCEV *Step = nullptr;
+  // Instruction that advances induction variable.
+  BinaryOperator *InductionBinOp = nullptr;
+  // Instructions used for type-casts of the induction variable,
+  // that are redundant when guarded with a runtime SCEV overflow check.
+  SmallVector<Instruction *, 2> RedundantCasts;
+};
+
+} // end namespace llvm
+
+#endif // LLVM_ANALYSIS_IVDESCRIPTORS_H