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+//===- llvm/Analysis/ValueTracking.h - Walk computations --------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains routines that help analyze properties that chains of
+// computations have.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ANALYSIS_VALUETRACKING_H
+#define LLVM_ANALYSIS_VALUETRACKING_H
+
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/Optional.h"
+#include "llvm/IR/CallSite.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/Instruction.h"
+#include "llvm/IR/Intrinsics.h"
+#include <cassert>
+#include <cstdint>
+
+namespace llvm {
+
+class AddOperator;
+class APInt;
+class AssumptionCache;
+class DataLayout;
+class DominatorTree;
+class GEPOperator;
+class IntrinsicInst;
+struct KnownBits;
+class Loop;
+class LoopInfo;
+class MDNode;
+class OptimizationRemarkEmitter;
+class StringRef;
+class TargetLibraryInfo;
+class Value;
+
+ /// Determine which bits of V are known to be either zero or one and return
+ /// them in the KnownZero/KnownOne bit sets.
+ ///
+ /// This function is defined on values with integer type, values with pointer
+ /// type, and vectors of integers. In the case
+ /// where V is a vector, the known zero and known one values are the
+ /// same width as the vector element, and the bit is set only if it is true
+ /// for all of the elements in the vector.
+ void computeKnownBits(const Value *V, KnownBits &Known,
+ const DataLayout &DL, unsigned Depth = 0,
+ AssumptionCache *AC = nullptr,
+ const Instruction *CxtI = nullptr,
+ const DominatorTree *DT = nullptr,
+ OptimizationRemarkEmitter *ORE = nullptr);
+
+ /// Returns the known bits rather than passing by reference.
+ KnownBits computeKnownBits(const Value *V, const DataLayout &DL,
+ unsigned Depth = 0, AssumptionCache *AC = nullptr,
+ const Instruction *CxtI = nullptr,
+ const DominatorTree *DT = nullptr,
+ OptimizationRemarkEmitter *ORE = nullptr);
+
+ /// Compute known bits from the range metadata.
+ /// \p KnownZero the set of bits that are known to be zero
+ /// \p KnownOne the set of bits that are known to be one
+ void computeKnownBitsFromRangeMetadata(const MDNode &Ranges,
+ KnownBits &Known);
+
+ /// Return true if LHS and RHS have no common bits set.
+ bool haveNoCommonBitsSet(const Value *LHS, const Value *RHS,
+ const DataLayout &DL,
+ AssumptionCache *AC = nullptr,
+ const Instruction *CxtI = nullptr,
+ const DominatorTree *DT = nullptr);
+
+ /// Return true if the given value is known to have exactly one bit set when
+ /// defined. For vectors return true if every element is known to be a power
+ /// of two when defined. Supports values with integer or pointer type and
+ /// vectors of integers. If 'OrZero' is set, then return true if the given
+ /// value is either a power of two or zero.
+ bool isKnownToBeAPowerOfTwo(const Value *V, const DataLayout &DL,
+ bool OrZero = false, unsigned Depth = 0,
+ AssumptionCache *AC = nullptr,
+ const Instruction *CxtI = nullptr,
+ const DominatorTree *DT = nullptr);
+
+ bool isOnlyUsedInZeroEqualityComparison(const Instruction *CxtI);
+
+ /// Return true if the given value is known to be non-zero when defined. For
+ /// vectors, return true if every element is known to be non-zero when
+ /// defined. For pointers, if the context instruction and dominator tree are
+ /// specified, perform context-sensitive analysis and return true if the
+ /// pointer couldn't possibly be null at the specified instruction.
+ /// Supports values with integer or pointer type and vectors of integers.
+ bool isKnownNonZero(const Value *V, const DataLayout &DL, unsigned Depth = 0,
+ AssumptionCache *AC = nullptr,
+ const Instruction *CxtI = nullptr,
+ const DominatorTree *DT = nullptr);
+
+ /// Returns true if the give value is known to be non-negative.
+ bool isKnownNonNegative(const Value *V, const DataLayout &DL,
+ unsigned Depth = 0,
+ AssumptionCache *AC = nullptr,
+ const Instruction *CxtI = nullptr,
+ const DominatorTree *DT = nullptr);
+
+ /// Returns true if the given value is known be positive (i.e. non-negative
+ /// and non-zero).
+ bool isKnownPositive(const Value *V, const DataLayout &DL, unsigned Depth = 0,
+ AssumptionCache *AC = nullptr,
+ const Instruction *CxtI = nullptr,
+ const DominatorTree *DT = nullptr);
+
+ /// Returns true if the given value is known be negative (i.e. non-positive
+ /// and non-zero).
+ bool isKnownNegative(const Value *V, const DataLayout &DL, unsigned Depth = 0,
+ AssumptionCache *AC = nullptr,
+ const Instruction *CxtI = nullptr,
+ const DominatorTree *DT = nullptr);
+
+ /// Return true if the given values are known to be non-equal when defined.
+ /// Supports scalar integer types only.
+ bool isKnownNonEqual(const Value *V1, const Value *V2, const DataLayout &DL,
+ AssumptionCache *AC = nullptr,
+ const Instruction *CxtI = nullptr,
+ const DominatorTree *DT = nullptr);
+
+ /// Return true if 'V & Mask' is known to be zero. We use this predicate to
+ /// simplify operations downstream. Mask is known to be zero for bits that V
+ /// cannot have.
+ ///
+ /// This function is defined on values with integer type, values with pointer
+ /// type, and vectors of integers. In the case
+ /// where V is a vector, the mask, known zero, and known one values are the
+ /// same width as the vector element, and the bit is set only if it is true
+ /// for all of the elements in the vector.
+ bool MaskedValueIsZero(const Value *V, const APInt &Mask,
+ const DataLayout &DL,
+ unsigned Depth = 0, AssumptionCache *AC = nullptr,
+ const Instruction *CxtI = nullptr,
+ const DominatorTree *DT = nullptr);
+
+ /// Return the number of times the sign bit of the register is replicated into
+ /// the other bits. We know that at least 1 bit is always equal to the sign
+ /// bit (itself), but other cases can give us information. For example,
+ /// immediately after an "ashr X, 2", we know that the top 3 bits are all
+ /// equal to each other, so we return 3. For vectors, return the number of
+ /// sign bits for the vector element with the mininum number of known sign
+ /// bits.
+ unsigned ComputeNumSignBits(const Value *Op, const DataLayout &DL,
+ unsigned Depth = 0, AssumptionCache *AC = nullptr,
+ const Instruction *CxtI = nullptr,
+ const DominatorTree *DT = nullptr);
+
+ /// This function computes the integer multiple of Base that equals V. If
+ /// successful, it returns true and returns the multiple in Multiple. If
+ /// unsuccessful, it returns false. Also, if V can be simplified to an
+ /// integer, then the simplified V is returned in Val. Look through sext only
+ /// if LookThroughSExt=true.
+ bool ComputeMultiple(Value *V, unsigned Base, Value *&Multiple,
+ bool LookThroughSExt = false,
+ unsigned Depth = 0);
+
+ /// Map a call instruction to an intrinsic ID. Libcalls which have equivalent
+ /// intrinsics are treated as-if they were intrinsics.
+ Intrinsic::ID getIntrinsicForCallSite(ImmutableCallSite ICS,
+ const TargetLibraryInfo *TLI);
+
+ /// Return true if we can prove that the specified FP value is never equal to
+ /// -0.0.
+ bool CannotBeNegativeZero(const Value *V, const TargetLibraryInfo *TLI,
+ unsigned Depth = 0);
+
+ /// Return true if we can prove that the specified FP value is either NaN or
+ /// never less than -0.0.
+ ///
+ /// NaN --> true
+ /// +0 --> true
+ /// -0 --> true
+ /// x > +0 --> true
+ /// x < -0 --> false
+ bool CannotBeOrderedLessThanZero(const Value *V, const TargetLibraryInfo *TLI);
+
+ /// Return true if the floating-point scalar value is not a NaN or if the
+ /// floating-point vector value has no NaN elements. Return false if a value
+ /// could ever be NaN.
+ bool isKnownNeverNaN(const Value *V);
+
+ /// Return true if we can prove that the specified FP value's sign bit is 0.
+ ///
+ /// NaN --> true/false (depending on the NaN's sign bit)
+ /// +0 --> true
+ /// -0 --> false
+ /// x > +0 --> true
+ /// x < -0 --> false
+ bool SignBitMustBeZero(const Value *V, const TargetLibraryInfo *TLI);
+
+ /// If the specified value can be set by repeating the same byte in memory,
+ /// return the i8 value that it is represented with. This is true for all i8
+ /// values obviously, but is also true for i32 0, i32 -1, i16 0xF0F0, double
+ /// 0.0 etc. If the value can't be handled with a repeated byte store (e.g.
+ /// i16 0x1234), return null.
+ Value *isBytewiseValue(Value *V);
+
+ /// Given an aggregrate and an sequence of indices, see if the scalar value
+ /// indexed is already around as a register, for example if it were inserted
+ /// directly into the aggregrate.
+ ///
+ /// If InsertBefore is not null, this function will duplicate (modified)
+ /// insertvalues when a part of a nested struct is extracted.
+ Value *FindInsertedValue(Value *V,
+ ArrayRef<unsigned> idx_range,
+ Instruction *InsertBefore = nullptr);
+
+ /// Analyze the specified pointer to see if it can be expressed as a base
+ /// pointer plus a constant offset. Return the base and offset to the caller.
+ Value *GetPointerBaseWithConstantOffset(Value *Ptr, int64_t &Offset,
+ const DataLayout &DL);
+ inline const Value *GetPointerBaseWithConstantOffset(const Value *Ptr,
+ int64_t &Offset,
+ const DataLayout &DL) {
+ return GetPointerBaseWithConstantOffset(const_cast<Value *>(Ptr), Offset,
+ DL);
+ }
+
+ /// Returns true if the GEP is based on a pointer to a string (array of
+ // \p CharSize integers) and is indexing into this string.
+ bool isGEPBasedOnPointerToString(const GEPOperator *GEP,
+ unsigned CharSize = 8);
+
+ /// Represents offset+length into a ConstantDataArray.
+ struct ConstantDataArraySlice {
+ /// ConstantDataArray pointer. nullptr indicates a zeroinitializer (a valid
+ /// initializer, it just doesn't fit the ConstantDataArray interface).
+ const ConstantDataArray *Array;
+
+ /// Slice starts at this Offset.
+ uint64_t Offset;
+
+ /// Length of the slice.
+ uint64_t Length;
+
+ /// Moves the Offset and adjusts Length accordingly.
+ void move(uint64_t Delta) {
+ assert(Delta < Length);
+ Offset += Delta;
+ Length -= Delta;
+ }
+
+ /// Convenience accessor for elements in the slice.
+ uint64_t operator[](unsigned I) const {
+ return Array==nullptr ? 0 : Array->getElementAsInteger(I + Offset);
+ }
+ };
+
+ /// Returns true if the value \p V is a pointer into a ConstantDataArray.
+ /// If successful \p Slice will point to a ConstantDataArray info object
+ /// with an appropriate offset.
+ bool getConstantDataArrayInfo(const Value *V, ConstantDataArraySlice &Slice,
+ unsigned ElementSize, uint64_t Offset = 0);
+
+ /// This function computes the length of a null-terminated C string pointed to
+ /// by V. If successful, it returns true and returns the string in Str. If
+ /// unsuccessful, it returns false. This does not include the trailing null
+ /// character by default. If TrimAtNul is set to false, then this returns any
+ /// trailing null characters as well as any other characters that come after
+ /// it.
+ bool getConstantStringInfo(const Value *V, StringRef &Str,
+ uint64_t Offset = 0, bool TrimAtNul = true);
+
+ /// If we can compute the length of the string pointed to by the specified
+ /// pointer, return 'len+1'. If we can't, return 0.
+ uint64_t GetStringLength(const Value *V, unsigned CharSize = 8);
+
+ /// This method strips off any GEP address adjustments and pointer casts from
+ /// the specified value, returning the original object being addressed. Note
+ /// that the returned value has pointer type if the specified value does. If
+ /// the MaxLookup value is non-zero, it limits the number of instructions to
+ /// be stripped off.
+ Value *GetUnderlyingObject(Value *V, const DataLayout &DL,
+ unsigned MaxLookup = 6);
+ inline const Value *GetUnderlyingObject(const Value *V, const DataLayout &DL,
+ unsigned MaxLookup = 6) {
+ return GetUnderlyingObject(const_cast<Value *>(V), DL, MaxLookup);
+ }
+
+ /// \brief This method is similar to GetUnderlyingObject except that it can
+ /// look through phi and select instructions and return multiple objects.
+ ///
+ /// If LoopInfo is passed, loop phis are further analyzed. If a pointer
+ /// accesses different objects in each iteration, we don't look through the
+ /// phi node. E.g. consider this loop nest:
+ ///
+ /// int **A;
+ /// for (i)
+ /// for (j) {
+ /// A[i][j] = A[i-1][j] * B[j]
+ /// }
+ ///
+ /// This is transformed by Load-PRE to stash away A[i] for the next iteration
+ /// of the outer loop:
+ ///
+ /// Curr = A[0]; // Prev_0
+ /// for (i: 1..N) {
+ /// Prev = Curr; // Prev = PHI (Prev_0, Curr)
+ /// Curr = A[i];
+ /// for (j: 0..N) {
+ /// Curr[j] = Prev[j] * B[j]
+ /// }
+ /// }
+ ///
+ /// Since A[i] and A[i-1] are independent pointers, getUnderlyingObjects
+ /// should not assume that Curr and Prev share the same underlying object thus
+ /// it shouldn't look through the phi above.
+ void GetUnderlyingObjects(Value *V, SmallVectorImpl<Value *> &Objects,
+ const DataLayout &DL, LoopInfo *LI = nullptr,
+ unsigned MaxLookup = 6);
+
+ /// This is a wrapper around GetUnderlyingObjects and adds support for basic
+ /// ptrtoint+arithmetic+inttoptr sequences.
+ bool getUnderlyingObjectsForCodeGen(const Value *V,
+ SmallVectorImpl<Value *> &Objects,
+ const DataLayout &DL);
+
+ /// Return true if the only users of this pointer are lifetime markers.
+ bool onlyUsedByLifetimeMarkers(const Value *V);
+
+ /// Return true if the instruction does not have any effects besides
+ /// calculating the result and does not have undefined behavior.
+ ///
+ /// This method never returns true for an instruction that returns true for
+ /// mayHaveSideEffects; however, this method also does some other checks in
+ /// addition. It checks for undefined behavior, like dividing by zero or
+ /// loading from an invalid pointer (but not for undefined results, like a
+ /// shift with a shift amount larger than the width of the result). It checks
+ /// for malloc and alloca because speculatively executing them might cause a
+ /// memory leak. It also returns false for instructions related to control
+ /// flow, specifically terminators and PHI nodes.
+ ///
+ /// If the CtxI is specified this method performs context-sensitive analysis
+ /// and returns true if it is safe to execute the instruction immediately
+ /// before the CtxI.
+ ///
+ /// If the CtxI is NOT specified this method only looks at the instruction
+ /// itself and its operands, so if this method returns true, it is safe to
+ /// move the instruction as long as the correct dominance relationships for
+ /// the operands and users hold.
+ ///
+ /// This method can return true for instructions that read memory;
+ /// for such instructions, moving them may change the resulting value.
+ bool isSafeToSpeculativelyExecute(const Value *V,
+ const Instruction *CtxI = nullptr,
+ const DominatorTree *DT = nullptr);
+
+ /// Returns true if the result or effects of the given instructions \p I
+ /// depend on or influence global memory.
+ /// Memory dependence arises for example if the instruction reads from
+ /// memory or may produce effects or undefined behaviour. Memory dependent
+ /// instructions generally cannot be reorderd with respect to other memory
+ /// dependent instructions or moved into non-dominated basic blocks.
+ /// Instructions which just compute a value based on the values of their
+ /// operands are not memory dependent.
+ bool mayBeMemoryDependent(const Instruction &I);
+
+ /// Return true if it is an intrinsic that cannot be speculated but also
+ /// cannot trap.
+ bool isAssumeLikeIntrinsic(const Instruction *I);
+
+ /// Return true if it is valid to use the assumptions provided by an
+ /// assume intrinsic, I, at the point in the control-flow identified by the
+ /// context instruction, CxtI.
+ bool isValidAssumeForContext(const Instruction *I, const Instruction *CxtI,
+ const DominatorTree *DT = nullptr);
+
+ enum class OverflowResult { AlwaysOverflows, MayOverflow, NeverOverflows };
+
+ OverflowResult computeOverflowForUnsignedMul(const Value *LHS,
+ const Value *RHS,
+ const DataLayout &DL,
+ AssumptionCache *AC,
+ const Instruction *CxtI,
+ const DominatorTree *DT);
+ OverflowResult computeOverflowForUnsignedAdd(const Value *LHS,
+ const Value *RHS,
+ const DataLayout &DL,
+ AssumptionCache *AC,
+ const Instruction *CxtI,
+ const DominatorTree *DT);
+ OverflowResult computeOverflowForSignedAdd(const Value *LHS, const Value *RHS,
+ const DataLayout &DL,
+ AssumptionCache *AC = nullptr,
+ const Instruction *CxtI = nullptr,
+ const DominatorTree *DT = nullptr);
+ /// This version also leverages the sign bit of Add if known.
+ OverflowResult computeOverflowForSignedAdd(const AddOperator *Add,
+ const DataLayout &DL,
+ AssumptionCache *AC = nullptr,
+ const Instruction *CxtI = nullptr,
+ const DominatorTree *DT = nullptr);
+
+ /// Returns true if the arithmetic part of the \p II 's result is
+ /// used only along the paths control dependent on the computation
+ /// not overflowing, \p II being an <op>.with.overflow intrinsic.
+ bool isOverflowIntrinsicNoWrap(const IntrinsicInst *II,
+ const DominatorTree &DT);
+
+ /// Return true if this function can prove that the instruction I will
+ /// always transfer execution to one of its successors (including the next
+ /// instruction that follows within a basic block). E.g. this is not
+ /// guaranteed for function calls that could loop infinitely.
+ ///
+ /// In other words, this function returns false for instructions that may
+ /// transfer execution or fail to transfer execution in a way that is not
+ /// captured in the CFG nor in the sequence of instructions within a basic
+ /// block.
+ ///
+ /// Undefined behavior is assumed not to happen, so e.g. division is
+ /// guaranteed to transfer execution to the following instruction even
+ /// though division by zero might cause undefined behavior.
+ bool isGuaranteedToTransferExecutionToSuccessor(const Instruction *I);
+
+ /// Returns true if this block does not contain a potential implicit exit.
+ /// This is equivelent to saying that all instructions within the basic block
+ /// are guaranteed to transfer execution to their successor within the basic
+ /// block. This has the same assumptions w.r.t. undefined behavior as the
+ /// instruction variant of this function.
+ bool isGuaranteedToTransferExecutionToSuccessor(const BasicBlock *BB);
+
+ /// Return true if this function can prove that the instruction I
+ /// is executed for every iteration of the loop L.
+ ///
+ /// Note that this currently only considers the loop header.
+ bool isGuaranteedToExecuteForEveryIteration(const Instruction *I,
+ const Loop *L);
+
+ /// Return true if this function can prove that I is guaranteed to yield
+ /// full-poison (all bits poison) if at least one of its operands are
+ /// full-poison (all bits poison).
+ ///
+ /// The exact rules for how poison propagates through instructions have
+ /// not been settled as of 2015-07-10, so this function is conservative
+ /// and only considers poison to be propagated in uncontroversial
+ /// cases. There is no attempt to track values that may be only partially
+ /// poison.
+ bool propagatesFullPoison(const Instruction *I);
+
+ /// Return either nullptr or an operand of I such that I will trigger
+ /// undefined behavior if I is executed and that operand has a full-poison
+ /// value (all bits poison).
+ const Value *getGuaranteedNonFullPoisonOp(const Instruction *I);
+
+ /// Return true if this function can prove that if PoisonI is executed
+ /// and yields a full-poison value (all bits poison), then that will
+ /// trigger undefined behavior.
+ ///
+ /// Note that this currently only considers the basic block that is
+ /// the parent of I.
+ bool programUndefinedIfFullPoison(const Instruction *PoisonI);
+
+ /// \brief Specific patterns of select instructions we can match.
+ enum SelectPatternFlavor {
+ SPF_UNKNOWN = 0,
+ SPF_SMIN, /// Signed minimum
+ SPF_UMIN, /// Unsigned minimum
+ SPF_SMAX, /// Signed maximum
+ SPF_UMAX, /// Unsigned maximum
+ SPF_FMINNUM, /// Floating point minnum
+ SPF_FMAXNUM, /// Floating point maxnum
+ SPF_ABS, /// Absolute value
+ SPF_NABS /// Negated absolute value
+ };
+
+ /// \brief Behavior when a floating point min/max is given one NaN and one
+ /// non-NaN as input.
+ enum SelectPatternNaNBehavior {
+ SPNB_NA = 0, /// NaN behavior not applicable.
+ SPNB_RETURNS_NAN, /// Given one NaN input, returns the NaN.
+ SPNB_RETURNS_OTHER, /// Given one NaN input, returns the non-NaN.
+ SPNB_RETURNS_ANY /// Given one NaN input, can return either (or
+ /// it has been determined that no operands can
+ /// be NaN).
+ };
+
+ struct SelectPatternResult {
+ SelectPatternFlavor Flavor;
+ SelectPatternNaNBehavior NaNBehavior; /// Only applicable if Flavor is
+ /// SPF_FMINNUM or SPF_FMAXNUM.
+ bool Ordered; /// When implementing this min/max pattern as
+ /// fcmp; select, does the fcmp have to be
+ /// ordered?
+
+ /// Return true if \p SPF is a min or a max pattern.
+ static bool isMinOrMax(SelectPatternFlavor SPF) {
+ return SPF != SPF_UNKNOWN && SPF != SPF_ABS && SPF != SPF_NABS;
+ }
+ };
+
+ /// Pattern match integer [SU]MIN, [SU]MAX and ABS idioms, returning the kind
+ /// and providing the out parameter results if we successfully match.
+ ///
+ /// If CastOp is not nullptr, also match MIN/MAX idioms where the type does
+ /// not match that of the original select. If this is the case, the cast
+ /// operation (one of Trunc,SExt,Zext) that must be done to transform the
+ /// type of LHS and RHS into the type of V is returned in CastOp.
+ ///
+ /// For example:
+ /// %1 = icmp slt i32 %a, i32 4
+ /// %2 = sext i32 %a to i64
+ /// %3 = select i1 %1, i64 %2, i64 4
+ ///
+ /// -> LHS = %a, RHS = i32 4, *CastOp = Instruction::SExt
+ ///
+ SelectPatternResult matchSelectPattern(Value *V, Value *&LHS, Value *&RHS,
+ Instruction::CastOps *CastOp = nullptr,
+ unsigned Depth = 0);
+ inline SelectPatternResult
+ matchSelectPattern(const Value *V, const Value *&LHS, const Value *&RHS,
+ Instruction::CastOps *CastOp = nullptr) {
+ Value *L = const_cast<Value*>(LHS);
+ Value *R = const_cast<Value*>(RHS);
+ auto Result = matchSelectPattern(const_cast<Value*>(V), L, R);
+ LHS = L;
+ RHS = R;
+ return Result;
+ }
+
+ /// Return the canonical comparison predicate for the specified
+ /// minimum/maximum flavor.
+ CmpInst::Predicate getMinMaxPred(SelectPatternFlavor SPF,
+ bool Ordered = false);
+
+ /// Return the inverse minimum/maximum flavor of the specified flavor.
+ /// For example, signed minimum is the inverse of signed maximum.
+ SelectPatternFlavor getInverseMinMaxFlavor(SelectPatternFlavor SPF);
+
+ /// Return the canonical inverse comparison predicate for the specified
+ /// minimum/maximum flavor.
+ CmpInst::Predicate getInverseMinMaxPred(SelectPatternFlavor SPF);
+
+ /// Return true if RHS is known to be implied true by LHS. Return false if
+ /// RHS is known to be implied false by LHS. Otherwise, return None if no
+ /// implication can be made.
+ /// A & B must be i1 (boolean) values or a vector of such values. Note that
+ /// the truth table for implication is the same as <=u on i1 values (but not
+ /// <=s!). The truth table for both is:
+ /// | T | F (B)
+ /// T | T | F
+ /// F | T | T
+ /// (A)
+ Optional<bool> isImpliedCondition(const Value *LHS, const Value *RHS,
+ const DataLayout &DL, bool LHSIsTrue = true,
+ unsigned Depth = 0);
+} // end namespace llvm
+
+#endif // LLVM_ANALYSIS_VALUETRACKING_H