llvm::ScalarEvolution Class Reference

The main scalar evolution driver. More...

#include "llvm/Analysis/ScalarEvolution.h"

Classes
struct	LoopInvariantPredicate

Public Types
enum	LoopDisposition { LoopVariant, LoopInvariant, LoopComputable }
	An enum describing the relationship between a SCEV and a loop. More...
enum	BlockDisposition { DoesNotDominateBlock, DominatesBlock, ProperlyDominatesBlock }
	An enum describing the relationship between a SCEV and a basic block. More...
enum	ExitCountKind { Exact, ConstantMaximum, SymbolicMaximum }
	The terms "backedge taken count" and "exit count" are used interchangeably to refer to the number of times the backedge of a loop has executed before the loop is exited. More...
enum	MonotonicPredicateType { MonotonicallyIncreasing, MonotonicallyDecreasing }
	A predicate is said to be monotonically increasing if may go from being false to being true as the loop iterates, but never the other way around. More...

Public Member Functions
	ScalarEvolution (Function &F, TargetLibraryInfo &TLI, AssumptionCache &AC, DominatorTree &DT, LoopInfo &LI)
	ScalarEvolution (ScalarEvolution &&Arg)
	~ScalarEvolution ()
LLVMContext &	getContext () const
bool	isSCEVable (Type *Ty) const
	Test if values of the given type are analyzable within the SCEV framework. More...
uint64_t	getTypeSizeInBits (Type *Ty) const
	Return the size in bits of the specified type, for which isSCEVable must return true. More...
Type *	getEffectiveSCEVType (Type *Ty) const
	Return a type with the same bitwidth as the given type and which represents how SCEV will treat the given type, for which isSCEVable must return true. More...
Type *	getWiderType (Type *Ty1, Type *Ty2) const
bool	instructionCouldExistWitthOperands (const SCEV *A, const SCEV *B)
	Return true if there exists a point in the program at which both A and B could be operands to the same instruction. More...
bool	containsAddRecurrence (const SCEV *S)
	Return true if the SCEV is a scAddRecExpr or it contains scAddRecExpr. More...
bool	willNotOverflow (Instruction::BinaryOps BinOp, bool Signed, const SCEV *LHS, const SCEV *RHS)
	Is operation BinOp between LHS and RHS provably does not have a signed/unsigned overflow (Signed)? More...
std::pair< SCEV::NoWrapFlags, bool >	getStrengthenedNoWrapFlagsFromBinOp (const OverflowingBinaryOperator *OBO)
	Parse NSW/NUW flags from add/sub/mul IR binary operation Op into SCEV no-wrap flags, and deduce flag[s] that aren't known yet. More...
void	registerUser (const SCEV *User, ArrayRef< const SCEV * > Ops)
	Notify this ScalarEvolution that User directly uses SCEVs in Ops. More...
bool	containsUndefs (const SCEV *S) const
	Return true if the SCEV expression contains an undef value. More...
bool	containsErasedValue (const SCEV *S) const
	Return true if the SCEV expression contains a Value that has been optimised out and is now a nullptr. More...
const SCEV *	getSCEV (Value *V)
	Return a SCEV expression for the full generality of the specified expression. More...
const SCEV *	getConstant (ConstantInt *V)
const SCEV *	getConstant (const APInt &Val)
const SCEV *	getConstant (Type *Ty, uint64_t V, bool isSigned=false)
const SCEV *	getLosslessPtrToIntExpr (const SCEV *Op, unsigned Depth=0)
const SCEV *	getPtrToIntExpr (const SCEV *Op, Type *Ty)
const SCEV *	getTruncateExpr (const SCEV *Op, Type *Ty, unsigned Depth=0)
const SCEV *	getZeroExtendExpr (const SCEV *Op, Type *Ty, unsigned Depth=0)
const SCEV *	getSignExtendExpr (const SCEV *Op, Type *Ty, unsigned Depth=0)
const SCEV *	getCastExpr (SCEVTypes Kind, const SCEV *Op, Type *Ty)
const SCEV *	getAnyExtendExpr (const SCEV *Op, Type *Ty)
	getAnyExtendExpr - Return a SCEV for the given operand extended with unspecified bits out to the given type. More...
const SCEV *	getAddExpr (SmallVectorImpl< const SCEV * > &Ops, SCEV::NoWrapFlags Flags=SCEV::FlagAnyWrap, unsigned Depth=0)
	Get a canonical add expression, or something simpler if possible. More...
const SCEV *	getAddExpr (const SCEV *LHS, const SCEV *RHS, SCEV::NoWrapFlags Flags=SCEV::FlagAnyWrap, unsigned Depth=0)
const SCEV *	getAddExpr (const SCEV *Op0, const SCEV *Op1, const SCEV *Op2, SCEV::NoWrapFlags Flags=SCEV::FlagAnyWrap, unsigned Depth=0)
const SCEV *	getMulExpr (SmallVectorImpl< const SCEV * > &Ops, SCEV::NoWrapFlags Flags=SCEV::FlagAnyWrap, unsigned Depth=0)
	Get a canonical multiply expression, or something simpler if possible. More...
const SCEV *	getMulExpr (const SCEV *LHS, const SCEV *RHS, SCEV::NoWrapFlags Flags=SCEV::FlagAnyWrap, unsigned Depth=0)
const SCEV *	getMulExpr (const SCEV *Op0, const SCEV *Op1, const SCEV *Op2, SCEV::NoWrapFlags Flags=SCEV::FlagAnyWrap, unsigned Depth=0)
const SCEV *	getUDivExpr (const SCEV *LHS, const SCEV *RHS)
	Get a canonical unsigned division expression, or something simpler if possible. More...
const SCEV *	getUDivExactExpr (const SCEV *LHS, const SCEV *RHS)
	Get a canonical unsigned division expression, or something simpler if possible. More...
const SCEV *	getURemExpr (const SCEV *LHS, const SCEV *RHS)
	Represents an unsigned remainder expression based on unsigned division. More...
const SCEV *	getAddRecExpr (const SCEV *Start, const SCEV *Step, const Loop *L, SCEV::NoWrapFlags Flags)
	Get an add recurrence expression for the specified loop. More...
const SCEV *	getAddRecExpr (SmallVectorImpl< const SCEV * > &Operands, const Loop *L, SCEV::NoWrapFlags Flags)
	Get an add recurrence expression for the specified loop. More...
const SCEV *	getAddRecExpr (const SmallVectorImpl< const SCEV * > &Operands, const Loop *L, SCEV::NoWrapFlags Flags)
Optional< std::pair< const SCEV *, SmallVector< const SCEVPredicate *, 3 > > >	createAddRecFromPHIWithCasts (const SCEVUnknown *SymbolicPHI)
	Checks if SymbolicPHI can be rewritten as an AddRecExpr under some Predicates. More...
const SCEV *	getGEPExpr (GEPOperator *GEP, const SmallVectorImpl< const SCEV * > &IndexExprs)
	Returns an expression for a GEP. More...
const SCEV *	getAbsExpr (const SCEV *Op, bool IsNSW)
const SCEV *	getMinMaxExpr (SCEVTypes Kind, SmallVectorImpl< const SCEV * > &Operands)
const SCEV *	getSequentialMinMaxExpr (SCEVTypes Kind, SmallVectorImpl< const SCEV * > &Operands)
const SCEV *	getSMaxExpr (const SCEV *LHS, const SCEV *RHS)
const SCEV *	getSMaxExpr (SmallVectorImpl< const SCEV * > &Operands)
const SCEV *	getUMaxExpr (const SCEV *LHS, const SCEV *RHS)
const SCEV *	getUMaxExpr (SmallVectorImpl< const SCEV * > &Operands)
const SCEV *	getSMinExpr (const SCEV *LHS, const SCEV *RHS)
const SCEV *	getSMinExpr (SmallVectorImpl< const SCEV * > &Operands)
const SCEV *	getUMinExpr (const SCEV *LHS, const SCEV *RHS, bool Sequential=false)
const SCEV *	getUMinExpr (SmallVectorImpl< const SCEV * > &Operands, bool Sequential=false)
const SCEV *	getUnknown (Value *V)
const SCEV *	getCouldNotCompute ()
const SCEV *	getZero (Type *Ty)
	Return a SCEV for the constant 0 of a specific type. More...
const SCEV *	getOne (Type *Ty)
	Return a SCEV for the constant 1 of a specific type. More...
const SCEV *	getMinusOne (Type *Ty)
	Return a SCEV for the constant -1 of a specific type. More...
const SCEV *	getSizeOfScalableVectorExpr (Type *IntTy, ScalableVectorType *ScalableTy)
	Return an expression for sizeof ScalableTy that is type IntTy, where ScalableTy is a scalable vector type. More...
const SCEV *	getSizeOfExpr (Type *IntTy, Type *AllocTy)
	Return an expression for the alloc size of AllocTy that is type IntTy. More...
const SCEV *	getStoreSizeOfExpr (Type *IntTy, Type *StoreTy)
	Return an expression for the store size of StoreTy that is type IntTy. More...
const SCEV *	getOffsetOfExpr (Type *IntTy, StructType *STy, unsigned FieldNo)
	Return an expression for offsetof on the given field with type IntTy. More...
const SCEV *	getNegativeSCEV (const SCEV *V, SCEV::NoWrapFlags Flags=SCEV::FlagAnyWrap)
	Return the SCEV object corresponding to -V. More...
const SCEV *	getNotSCEV (const SCEV *V)
	Return the SCEV object corresponding to ~V. More...
const SCEV *	getMinusSCEV (const SCEV *LHS, const SCEV *RHS, SCEV::NoWrapFlags Flags=SCEV::FlagAnyWrap, unsigned Depth=0)
	Return LHS-RHS. More...
const SCEV *	getUDivCeilSCEV (const SCEV *N, const SCEV *D)
	Compute ceil(N / D). More...
const SCEV *	getTruncateOrZeroExtend (const SCEV *V, Type *Ty, unsigned Depth=0)
	Return a SCEV corresponding to a conversion of the input value to the specified type. More...
const SCEV *	getTruncateOrSignExtend (const SCEV *V, Type *Ty, unsigned Depth=0)
	Return a SCEV corresponding to a conversion of the input value to the specified type. More...
const SCEV *	getNoopOrZeroExtend (const SCEV *V, Type *Ty)
	Return a SCEV corresponding to a conversion of the input value to the specified type. More...
const SCEV *	getNoopOrSignExtend (const SCEV *V, Type *Ty)
	Return a SCEV corresponding to a conversion of the input value to the specified type. More...
const SCEV *	getNoopOrAnyExtend (const SCEV *V, Type *Ty)
	Return a SCEV corresponding to a conversion of the input value to the specified type. More...
const SCEV *	getTruncateOrNoop (const SCEV *V, Type *Ty)
	Return a SCEV corresponding to a conversion of the input value to the specified type. More...
const SCEV *	getUMaxFromMismatchedTypes (const SCEV *LHS, const SCEV *RHS)
	Promote the operands to the wider of the types using zero-extension, and then perform a umax operation with them. More...
const SCEV *	getUMinFromMismatchedTypes (const SCEV *LHS, const SCEV *RHS, bool Sequential=false)
	Promote the operands to the wider of the types using zero-extension, and then perform a umin operation with them. More...
const SCEV *	getUMinFromMismatchedTypes (SmallVectorImpl< const SCEV * > &Ops, bool Sequential=false)
	Promote the operands to the wider of the types using zero-extension, and then perform a umin operation with them. More...
const SCEV *	getPointerBase (const SCEV *V)
	Transitively follow the chain of pointer-type operands until reaching a SCEV that does not have a single pointer operand. More...
const SCEV *	removePointerBase (const SCEV *S)
	Compute an expression equivalent to S - getPointerBase(S). More...
const SCEV *	getSCEVAtScope (const SCEV *S, const Loop *L)
	Return a SCEV expression for the specified value at the specified scope in the program. More...
const SCEV *	getSCEVAtScope (Value *V, const Loop *L)
	This is a convenience function which does getSCEVAtScope(getSCEV(V), L). More...
bool	isLoopEntryGuardedByCond (const Loop *L, ICmpInst::Predicate Pred, const SCEV *LHS, const SCEV *RHS)
	Test whether entry to the loop is protected by a conditional between LHS and RHS. More...
bool	isBasicBlockEntryGuardedByCond (const BasicBlock *BB, ICmpInst::Predicate Pred, const SCEV *LHS, const SCEV *RHS)
	Test whether entry to the basic block is protected by a conditional between LHS and RHS. More...
bool	isLoopBackedgeGuardedByCond (const Loop *L, ICmpInst::Predicate Pred, const SCEV *LHS, const SCEV *RHS)
	Test whether the backedge of the loop is protected by a conditional between LHS and RHS. More...
const SCEV *	getTripCountFromExitCount (const SCEV *ExitCount, bool Extend=true)
	Convert from an "exit count" (i.e. More...
unsigned	getSmallConstantTripCount (const Loop *L)
	Returns the exact trip count of the loop if we can compute it, and the result is a small constant. More...
unsigned	getSmallConstantTripCount (const Loop *L, const BasicBlock *ExitingBlock)
	Return the exact trip count for this loop if we exit through ExitingBlock. More...
unsigned	getSmallConstantMaxTripCount (const Loop *L)
	Returns the upper bound of the loop trip count as a normal unsigned value. More...
const SCEV *	getConstantMaxTripCountFromArray (const Loop *L)
	Returns the upper bound of the loop trip count infered from array size. More...
unsigned	getSmallConstantTripMultiple (const Loop *L, const SCEV *ExitCount)
	Returns the largest constant divisor of the trip count as a normal unsigned value, if possible. More...
unsigned	getSmallConstantTripMultiple (const Loop *L)
	Returns the largest constant divisor of the trip count of the loop. More...
unsigned	getSmallConstantTripMultiple (const Loop *L, const BasicBlock *ExitingBlock)
	Returns the largest constant divisor of the trip count of this loop as a normal unsigned value, if possible. More...
const SCEV *	getExitCount (const Loop *L, const BasicBlock *ExitingBlock, ExitCountKind Kind=Exact)
	Return the number of times the backedge executes before the given exit would be taken; if not exactly computable, return SCEVCouldNotCompute. More...
const SCEV *	getBackedgeTakenCount (const Loop *L, ExitCountKind Kind=Exact)
	If the specified loop has a predictable backedge-taken count, return it, otherwise return a SCEVCouldNotCompute object. More...
const SCEV *	getPredicatedBackedgeTakenCount (const Loop *L, SmallVector< const SCEVPredicate *, 4 > &Predicates)
	Similar to getBackedgeTakenCount, except it will add a set of SCEV predicates to Predicates that are required to be true in order for the answer to be correct. More...
const SCEV *	getConstantMaxBackedgeTakenCount (const Loop *L)
	When successful, this returns a SCEVConstant that is greater than or equal to (i.e. More...
const SCEV *	getSymbolicMaxBackedgeTakenCount (const Loop *L)
	When successful, this returns a SCEV that is greater than or equal to (i.e. More...
bool	isBackedgeTakenCountMaxOrZero (const Loop *L)
	Return true if the backedge taken count is either the value returned by getConstantMaxBackedgeTakenCount or zero. More...
bool	hasLoopInvariantBackedgeTakenCount (const Loop *L)
	Return true if the specified loop has an analyzable loop-invariant backedge-taken count. More...
void	forgetAllLoops ()
void	forgetLoop (const Loop *L)
	This method should be called by the client when it has changed a loop in a way that may effect ScalarEvolution's ability to compute a trip count, or if the loop is deleted. More...
void	forgetTopmostLoop (const Loop *L)
void	forgetValue (Value *V)
	This method should be called by the client when it has changed a value in a way that may effect its value, or which may disconnect it from a def-use chain linking it to a loop. More...
void	forgetLoopDispositions (const Loop *L)
	Called when the client has changed the disposition of values in this loop. More...
uint32_t	GetMinTrailingZeros (const SCEV *S)
	Determine the minimum number of zero bits that S is guaranteed to end in (at every loop iteration). More...
ConstantRange	getUnsignedRange (const SCEV *S)
	Determine the unsigned range for a particular SCEV. More...
APInt	getUnsignedRangeMin (const SCEV *S)
	Determine the min of the unsigned range for a particular SCEV. More...
APInt	getUnsignedRangeMax (const SCEV *S)
	Determine the max of the unsigned range for a particular SCEV. More...
ConstantRange	getSignedRange (const SCEV *S)
	Determine the signed range for a particular SCEV. More...
APInt	getSignedRangeMin (const SCEV *S)
	Determine the min of the signed range for a particular SCEV. More...
APInt	getSignedRangeMax (const SCEV *S)
	Determine the max of the signed range for a particular SCEV. More...
bool	isKnownNegative (const SCEV *S)
	Test if the given expression is known to be negative. More...
bool	isKnownPositive (const SCEV *S)
	Test if the given expression is known to be positive. More...
bool	isKnownNonNegative (const SCEV *S)
	Test if the given expression is known to be non-negative. More...
bool	isKnownNonPositive (const SCEV *S)
	Test if the given expression is known to be non-positive. More...
bool	isKnownNonZero (const SCEV *S)
	Test if the given expression is known to be non-zero. More...
std::pair< const SCEV *, const SCEV * >	SplitIntoInitAndPostInc (const Loop *L, const SCEV *S)
	Splits SCEV expression S into two SCEVs. More...
bool	isKnownViaInduction (ICmpInst::Predicate Pred, const SCEV *LHS, const SCEV *RHS)
	We'd like to check the predicate on every iteration of the most dominated loop between loops used in LHS and RHS. More...
bool	isKnownPredicate (ICmpInst::Predicate Pred, const SCEV *LHS, const SCEV *RHS)
	Test if the given expression is known to satisfy the condition described by Pred, LHS, and RHS. More...
Optional< bool >	evaluatePredicate (ICmpInst::Predicate Pred, const SCEV *LHS, const SCEV *RHS)
	Check whether the condition described by Pred, LHS, and RHS is true or false. More...
bool	isKnownPredicateAt (ICmpInst::Predicate Pred, const SCEV *LHS, const SCEV *RHS, const Instruction *CtxI)
	Test if the given expression is known to satisfy the condition described by Pred, LHS, and RHS in the given Context. More...
Optional< bool >	evaluatePredicateAt (ICmpInst::Predicate Pred, const SCEV *LHS, const SCEV *RHS, const Instruction *CtxI)
	Check whether the condition described by Pred, LHS, and RHS is true or false in the given Context. More...
bool	isKnownOnEveryIteration (ICmpInst::Predicate Pred, const SCEVAddRecExpr *LHS, const SCEV *RHS)
	Test if the condition described by Pred, LHS, RHS is known to be true on every iteration of the loop of the recurrency LHS. More...
Optional< MonotonicPredicateType >	getMonotonicPredicateType (const SCEVAddRecExpr *LHS, ICmpInst::Predicate Pred)
	If, for all loop invariant X, the predicate "LHS `Pred` X" is monotonically increasing or decreasing, returns Some(MonotonicallyIncreasing) and Some(MonotonicallyDecreasing) respectively. More...
Optional< LoopInvariantPredicate >	getLoopInvariantPredicate (ICmpInst::Predicate Pred, const SCEV *LHS, const SCEV *RHS, const Loop *L)
	If the result of the predicate LHS Pred RHS is loop invariant with respect to L, return a LoopInvariantPredicate with LHS and RHS being invariants, available at L's entry. More...
Optional< LoopInvariantPredicate >	getLoopInvariantExitCondDuringFirstIterations (ICmpInst::Predicate Pred, const SCEV *LHS, const SCEV *RHS, const Loop *L, const Instruction *CtxI, const SCEV *MaxIter)
	If the result of the predicate LHS Pred RHS is loop invariant with respect to L at given Context during at least first MaxIter iterations, return a LoopInvariantPredicate with LHS and RHS being invariants, available at L's entry. More...
bool	SimplifyICmpOperands (ICmpInst::Predicate &Pred, const SCEV *&LHS, const SCEV *&RHS, unsigned Depth=0, bool ControllingFiniteLoop=false)
	Simplify LHS and RHS in a comparison with predicate Pred. More...
LoopDisposition	getLoopDisposition (const SCEV *S, const Loop *L)
	Return the "disposition" of the given SCEV with respect to the given loop. More...
bool	isLoopInvariant (const SCEV *S, const Loop *L)
	Return true if the value of the given SCEV is unchanging in the specified loop. More...
bool	isAvailableAtLoopEntry (const SCEV *S, const Loop *L)
	Determine if the SCEV can be evaluated at loop's entry. More...
bool	hasComputableLoopEvolution (const SCEV *S, const Loop *L)
	Return true if the given SCEV changes value in a known way in the specified loop. More...
BlockDisposition	getBlockDisposition (const SCEV *S, const BasicBlock *BB)
	Return the "disposition" of the given SCEV with respect to the given block. More...
bool	dominates (const SCEV *S, const BasicBlock *BB)
	Return true if elements that makes up the given SCEV dominate the specified basic block. More...
bool	properlyDominates (const SCEV *S, const BasicBlock *BB)
	Return true if elements that makes up the given SCEV properly dominate the specified basic block. More...
bool	hasOperand (const SCEV *S, const SCEV *Op) const
	Test whether the given SCEV has Op as a direct or indirect operand. More...
const SCEV *	getElementSize (Instruction *Inst)
	Return the size of an element read or written by Inst. More...
void	print (raw_ostream &OS) const
void	verify () const
bool	invalidate (Function &F, const PreservedAnalyses &PA, FunctionAnalysisManager::Invalidator &Inv)
const DataLayout &	getDataLayout () const
	Return the DataLayout associated with the module this SCEV instance is operating on. More...
const SCEVPredicate *	getEqualPredicate (const SCEV *LHS, const SCEV *RHS)
const SCEVPredicate *	getComparePredicate (ICmpInst::Predicate Pred, const SCEV *LHS, const SCEV *RHS)
const SCEVPredicate *	getWrapPredicate (const SCEVAddRecExpr *AR, SCEVWrapPredicate::IncrementWrapFlags AddedFlags)
const SCEV *	rewriteUsingPredicate (const SCEV *S, const Loop *L, const SCEVPredicate &A)
	Re-writes the SCEV according to the Predicates in A. More...
const SCEVAddRecExpr *	convertSCEVToAddRecWithPredicates (const SCEV *S, const Loop *L, SmallPtrSetImpl< const SCEVPredicate * > &Preds)
	Tries to convert the S expression to an AddRec expression, adding additional predicates to Preds as required. More...
Optional< APInt >	computeConstantDifference (const SCEV *LHS, const SCEV *RHS)
	Compute LHS - RHS and returns the result as an APInt if it is a constant, and None if it isn't. More...
void	setNoWrapFlags (SCEVAddRecExpr *AddRec, SCEV::NoWrapFlags Flags)
	Update no-wrap flags of an AddRec. More...
const SCEV *	applyLoopGuards (const SCEV *Expr, const Loop *L)
	Try to apply information from loop guards for L to Expr. More...
bool	loopHasNoAbnormalExits (const Loop *L)
	Return true if the loop has no abnormal exits. More...
bool	loopIsFiniteByAssumption (const Loop *L)
	Return true if this loop is finite by assumption. More...

Static Public Member Functions
static LLVM_NODISCARD SCEV::NoWrapFlags	maskFlags (SCEV::NoWrapFlags Flags, int Mask)
	Convenient NoWrapFlags manipulation that hides enum casts and is visible in the ScalarEvolution name space. More...
static LLVM_NODISCARD SCEV::NoWrapFlags	setFlags (SCEV::NoWrapFlags Flags, SCEV::NoWrapFlags OnFlags)
static LLVM_NODISCARD SCEV::NoWrapFlags	clearFlags (SCEV::NoWrapFlags Flags, SCEV::NoWrapFlags OffFlags)
static LLVM_NODISCARD bool	hasFlags (SCEV::NoWrapFlags Flags, SCEV::NoWrapFlags TestFlags)

Friends
class	ScalarEvolutionsTest
class	SCEVCallbackVH
class	SCEVExpander
class	SCEVUnknown

Detailed Description

The main scalar evolution driver.

Because client code (intentionally) can't do much with the SCEV objects directly, they must ask this class for services.

Definition at line 449 of file ScalarEvolution.h.

Member Enumeration Documentation

BlockDisposition

enum llvm::ScalarEvolution::BlockDisposition

An enum describing the relationship between a SCEV and a basic block.

Enumerator
DoesNotDominateBlock	The SCEV does not dominate the block.
DominatesBlock	The SCEV dominates the block.
ProperlyDominatesBlock	The SCEV properly dominates the block.

Definition at line 461 of file ScalarEvolution.h.

ExitCountKind

enum llvm::ScalarEvolution::ExitCountKind

The terms "backedge taken count" and "exit count" are used interchangeably to refer to the number of times the backedge of a loop has executed before the loop is exited.

Enumerator
Exact	An expression exactly describing the number of times the backedge has executed when a loop is exited.
ConstantMaximum	A constant which provides an upper bound on the exact trip count.
SymbolicMaximum	An expression which provides an upper bound on the exact trip count.

Definition at line 845 of file ScalarEvolution.h.

LoopDisposition

enum llvm::ScalarEvolution::LoopDisposition

An enum describing the relationship between a SCEV and a loop.

Enumerator
LoopVariant	The SCEV is loop-variant (unknown).
LoopInvariant	The SCEV is loop-invariant.
LoopComputable	The SCEV varies predictably with the loop.

Definition at line 454 of file ScalarEvolution.h.

MonotonicPredicateType

enum llvm::ScalarEvolution::MonotonicPredicateType

A predicate is said to be monotonically increasing if may go from being false to being true as the loop iterates, but never the other way around.

A predicate is said to be monotonically decreasing if may go from being true to being false as the loop iterates, but never the other way around.

Enumerator
MonotonicallyIncreasing
MonotonicallyDecreasing

Definition at line 1063 of file ScalarEvolution.h.

Constructor & Destructor Documentation

ScalarEvolution() [1/2]

ScalarEvolution::ScalarEvolution	(	Function &	F,
		TargetLibraryInfo &	TLI,
		AssumptionCache &	AC,
		DominatorTree &	DT,
		LoopInfo &	LI
	)

Definition at line 12894 of file ScalarEvolution.cpp.

References F, and llvm::Intrinsic::getName().

Referenced by willNotOverflow().

ScalarEvolution() [2/2]

ScalarEvolution::ScalarEvolution

(

ScalarEvolution &&

Arg

)

Definition at line 12915 of file ScalarEvolution.cpp.

References Arg.

~ScalarEvolution()

ScalarEvolution::~ScalarEvolution

(

)

Definition at line 12946 of file ScalarEvolution.cpp.

References assert(), and llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::clear().

Member Function Documentation

applyLoopGuards()

const SCEV * ScalarEvolution::applyLoopGuards	(	const SCEV *	Expr,
		const Loop *	L
	)

Try to apply information from loop guards for L to Expr.

Definition at line 14375 of file ScalarEvolution.cpp.

References llvm::AssumptionCache::assumptions(), C1, Cond, containsAddRecurrence(), llvm::DominatorTree::dominates(), E, llvm::SmallVectorImpl< T >::emplace_back(), llvm::DenseMapBase< DenseMap< KeyT, ValueT, DenseMapInfo< KeyT >, llvm::detail::DenseMapPair< KeyT, ValueT > >, KeyT, ValueT, DenseMapInfo< KeyT >, llvm::detail::DenseMapPair< KeyT, ValueT > >::empty(), llvm::DenseMapBase< DenseMap< KeyT, ValueT, DenseMapInfo< KeyT >, llvm::detail::DenseMapPair< KeyT, ValueT > >, KeyT, ValueT, DenseMapInfo< KeyT >, llvm::detail::DenseMapPair< KeyT, ValueT > >::erase(), getAddExpr(), llvm::BranchInst::getCondition(), getConstant(), llvm::LoopBase< BlockT, LoopT >::getHeader(), llvm::LoopBase< BlockT, LoopT >::getLoopPredecessor(), getMinusSCEV(), getMulExpr(), getOne(), getSCEV(), getSMaxExpr(), getSMinExpr(), llvm::BranchInst::getSuccessor(), llvm::CmpInst::getSwappedPredicate(), llvm::Value::getType(), getUDivExpr(), getUMaxExpr(), getUMinExpr(), llvm::SCEVConstant::getValue(), I, llvm::CmpInst::ICMP_EQ, llvm::CmpInst::ICMP_NE, llvm::CmpInst::ICMP_SGE, llvm::CmpInst::ICMP_SGT, llvm::CmpInst::ICMP_SLE, llvm::CmpInst::ICMP_SLT, llvm::CmpInst::ICMP_UGE, llvm::CmpInst::ICMP_UGT, llvm::CmpInst::ICMP_ULE, llvm::CmpInst::ICMP_ULT, llvm::DenseMapBase< DenseMap< KeyT, ValueT, DenseMapInfo< KeyT >, llvm::detail::DenseMapPair< KeyT, ValueT > >, KeyT, ValueT, DenseMapInfo< KeyT >, llvm::detail::DenseMapPair< KeyT, ValueT > >::insert(), llvm::SmallPtrSetImpl< PtrType >::insert(), llvm::Constant::isNullValue(), llvm::BranchInst::isUnconditional(), LHS, llvm::PatternMatch::m_LogicalAnd(), llvm::PatternMatch::m_LogicalOr(), llvm::PatternMatch::m_Value(), llvm::ConstantRange::makeExactICmpRegion(), llvm::PatternMatch::match(), llvm::SmallVectorImpl< T >::pop_back_val(), llvm::reverse(), Rewriter, RHS, llvm::ConstantRange::sub(), and std::swap().

Referenced by llvm::LoopVectorizationCostModel::computeMaxVF(), and getSmallConstantTripMultiple().

clearFlags()

static LLVM_NODISCARD SCEV::NoWrapFlags llvm::ScalarEvolution::clearFlags ( SCEV::NoWrapFlags  Flags, SCEV::NoWrapFlags  OffFlags  )

inlinestatic

Definition at line 478 of file ScalarEvolution.h.

computeConstantDifference()

Optional< APInt > ScalarEvolution::computeConstantDifference	(	const SCEV *	LHS,
		const SCEV *	RHS
	)

Compute LHS - RHS and returns the result as an APInt if it is a constant, and None if it isn't.

This is intended to be a cheaper version of getMinusSCEV. We can be frugal here since we just bail out of actually constructing and canonicalizing an expression in the cases where the result isn't going to be a constant.

Definition at line 11364 of file ScalarEvolution.cpp.

References C1, llvm::SCEV::getType(), getTypeSizeInBits(), llvm::CodeGenOpt::Less, M, and llvm::None.

Referenced by SalvageDVI().

containsAddRecurrence()

bool ScalarEvolution::containsAddRecurrence

(

const SCEV *

S

)

Return true if the SCEV is a scAddRecExpr or it contains scAddRecExpr.

The result will be cached in HasRecMap.

Definition at line 4352 of file ScalarEvolution.cpp.

References llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::end(), llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::find(), I, llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::insert(), S, and llvm::SCEVExprContains().

Referenced by applyLoopGuards().

containsErasedValue()

bool ScalarEvolution::containsErasedValue

(

const SCEV *

S

)

const

Return true if the SCEV expression contains a Value that has been optimised out and is now a nullptr.

Definition at line 12824 of file ScalarEvolution.cpp.

References S, and llvm::SCEVExprContains().

Referenced by SalvageDVI().

containsUndefs()

bool ScalarEvolution::containsUndefs

(

const SCEV *

S

)

const

Return true if the SCEV expression contains an undef value.

Definition at line 12815 of file ScalarEvolution.cpp.

References S, and llvm::SCEVExprContains().

Referenced by DbgGatherSalvagableDVI(), GetInductionVariable(), SalvageDVI(), and verify().

convertSCEVToAddRecWithPredicates()

const SCEVAddRecExpr * ScalarEvolution::convertSCEVToAddRecWithPredicates	(	const SCEV *	S,
		const Loop *	L,
		SmallPtrSetImpl< const SCEVPredicate * > &	Preds
	)

Tries to convert the S expression to an AddRec expression, adding additional predicates to Preds as required.

Definition at line 13965 of file ScalarEvolution.cpp.

References llvm::SmallPtrSetImpl< PtrType >::insert(), P, rewrite(), and S.

Referenced by llvm::PredicatedScalarEvolution::getAsAddRec().

createAddRecFromPHIWithCasts()

Optional< std::pair< const SCEV *, SmallVector< const SCEVPredicate *, 3 > > > ScalarEvolution::createAddRecFromPHIWithCasts

(

const SCEVUnknown *

SymbolicPHI

)

Checks if SymbolicPHI can be rewritten as an AddRecExpr under some Predicates.

If successful return these <AddRecExpr, Predicates>; The function is intended to be called from PSCEV (the caller will decide whether to actually add the predicates and carry out the rewrites).

Definition at line 5501 of file ScalarEvolution.cpp.

References assert(), llvm::SCEVUnknown::getValue(), I, isIntegerLoopHeaderPHI(), and llvm::None.

dominates()

bool ScalarEvolution::dominates	(	const SCEV *	S,
		const BasicBlock *	BB
	)

Return true if elements that makes up the given SCEV dominate the specified basic block.

Definition at line 13334 of file ScalarEvolution.cpp.

References BB, DominatesBlock, getBlockDisposition(), and S.

Referenced by llvm::isSafeToExpandAt().

evaluatePredicate()

Optional< bool > ScalarEvolution::evaluatePredicate	(	ICmpInst::Predicate	Pred,
		const SCEV *	LHS,
		const SCEV *	RHS
	)

Check whether the condition described by Pred, LHS, and RHS is true or false.

If we know it, return the evaluation of this condition. If neither is proved, return None.

Definition at line 10418 of file ScalarEvolution.cpp.

References llvm::CmpInst::getInversePredicate(), isKnownPredicate(), LHS, llvm::None, and RHS.

Referenced by countToEliminateCompares(), and evaluatePredicateAt().

evaluatePredicateAt()

Optional< bool > ScalarEvolution::evaluatePredicateAt	(	ICmpInst::Predicate	Pred,
		const SCEV *	LHS,
		const SCEV *	RHS,
		const Instruction *	CtxI
	)

Check whether the condition described by Pred, LHS, and RHS is true or false in the given Context.

If we know it, return the evaluation of this condition. If neither is proved, return None.

Definition at line 10436 of file ScalarEvolution.cpp.

References evaluatePredicate(), llvm::CmpInst::getInversePredicate(), llvm::Instruction::getParent(), isBasicBlockEntryGuardedByCond(), LHS, llvm::None, and RHS.

forgetAllLoops()

void ScalarEvolution::forgetAllLoops

(

)

Definition at line 8006 of file ScalarEvolution.cpp.

References llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::clear().

Referenced by llvm::UnrollLoop().

forgetLoop()

void ScalarEvolution::forgetLoop

(

const Loop *

L

)

This method should be called by the client when it has changed a loop in a way that may effect ScalarEvolution's ability to compute a trip count, or if the loop is deleted.

This call is potentially expensive for large loop bodies.

Definition at line 8030 of file ScalarEvolution.cpp.

References I, and llvm::SmallVectorImpl< T >::pop_back_val().

Referenced by llvm::breakLoopBackedge(), llvm::deleteDeadLoop(), deleteLoopIfDead(), DoFlattenLoopPair(), llvm::InnerLoopVectorizer::fixVectorizedLoop(), forgetTopmostLoop(), llvm::formLCSSA(), separateNestedLoop(), llvm::splitLoopBound(), llvm::UnrollAndJamLoop(), unswitchNontrivialInvariants(), unswitchTrivialBranch(), and unswitchTrivialSwitch().

forgetLoopDispositions()

void ScalarEvolution::forgetLoopDispositions

(

const Loop *

L

)

Called when the client has changed the disposition of values in this loop.

We don't have a way to invalidate per-loop dispositions. Clear and recompute is simpler.

Definition at line 8117 of file ScalarEvolution.cpp.

Referenced by isLoopDead(), simplifyOneLoop(), and sinkLoopInvariantInstructions().

forgetTopmostLoop()

void ScalarEvolution::forgetTopmostLoop

(

const Loop *

L

)

Definition at line 8086 of file ScalarEvolution.cpp.

References forgetLoop(), and llvm::LoopBase< BlockT, LoopT >::getOutermostLoop().

Referenced by llvm::peelLoop(), simplifyLoopCFG(), llvm::UnrollLoop(), llvm::UnrollRuntimeLoopRemainder(), unswitchNontrivialInvariants(), unswitchTrivialBranch(), and unswitchTrivialSwitch().

forgetValue()

void ScalarEvolution::forgetValue

(

Value *

V

)

This method should be called by the client when it has changed a value in a way that may effect its value, or which may disconnect it from a def-use chain linking it to a loop.

Definition at line 8090 of file ScalarEvolution.cpp.

References llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::end(), llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::find_as(), I, llvm::SmallPtrSetImpl< PtrType >::insert(), llvm::SmallVectorImpl< T >::pop_back_val(), and PushDefUseChildren().

Referenced by cloneLoopBlocks(), llvm::formLCSSAForInstructions(), moveInstructionBefore(), llvm::rewriteLoopExitValues(), RewriteUsesOfClonedInstructions(), simplifyOneLoop(), and GeneratedRTChecks::~GeneratedRTChecks().

getAbsExpr()

const SCEV * ScalarEvolution::getAbsExpr	(	const SCEV *	Op,
		bool	IsNSW
	)

Definition at line 3754 of file ScalarEvolution.cpp.

References llvm::SCEV::FlagAnyWrap, llvm::SCEV::FlagNSW, getNegativeSCEV(), and getSMaxExpr().

getAddExpr() [1/3]

const SCEV* llvm::ScalarEvolution::getAddExpr ( const SCEV *  LHS, const SCEV *  RHS, SCEV::NoWrapFlags  Flags = SCEV::FlagAnyWrap, unsigned  Depth = 0  )

inline

Definition at line 569 of file ScalarEvolution.h.

References llvm::Depth, getAddExpr(), LHS, and RHS.

getAddExpr() [2/3]

const SCEV* llvm::ScalarEvolution::getAddExpr ( const SCEV *  Op0, const SCEV *  Op1, const SCEV *  Op2, SCEV::NoWrapFlags  Flags = SCEV::FlagAnyWrap, unsigned  Depth = 0  )

inline

Definition at line 575 of file ScalarEvolution.h.

References llvm::Depth, and getAddExpr().

getAddExpr() [3/3]

const SCEV * ScalarEvolution::getAddExpr	(	SmallVectorImpl< const SCEV * > &	Ops,
		SCEV::NoWrapFlags	Flags = SCEV::FlagAnyWrap,
		unsigned	Depth = 0
	)

Get a canonical add expression, or something simpler if possible.

Definition at line 2453 of file ScalarEvolution.cpp.

References llvm::APInt::abs(), AddOpsInlineThreshold, llvm::SmallVectorImpl< T >::append(), assert(), B, llvm::BasicBlock::begin(), llvm::BitWidth, C1, llvm::SmallVectorImpl< T >::clear(), CollectAddOperandsWithScales(), llvm::count_if(), llvm::Depth, llvm::DominatorTree::dominates(), llvm::numbers::e, llvm::SmallVectorImpl< T >::erase(), f(), llvm::SCEV::FlagAnyWrap, llvm::SCEV::FlagNSW, llvm::SCEV::FlagNUW, llvm::SCEV::FlagNW, getAddRecExpr(), getAnyExtendExpr(), getConstant(), getEffectiveSCEVType(), llvm::LoopBase< BlockT, LoopT >::getHeader(), llvm::SCEVAddRecExpr::getLoop(), getMulExpr(), llvm::SCEVNAryExpr::getNoWrapFlags(), llvm::User::getNumOperands(), llvm::SCEVNAryExpr::getNumOperands(), getOne(), llvm::User::getOperand(), llvm::SCEVNAryExpr::getOperand(), llvm::SCEVAddRecExpr::getStart(), getTruncateExpr(), llvm::Intrinsic::getType(), getTypeSizeInBits(), getUDivExpr(), getZero(), GroupByComplexity(), hasFlags(), hasHugeExpression(), i, isAvailableAtLoopEntry(), llvm::APInt::isSignBitSet(), j(), LHS, M, maskFlags(), MaxArithDepth, Mul, llvm::SCEVNAryExpr::op_begin(), llvm::User::op_begin(), llvm::SCEVNAryExpr::op_end(), llvm::User::op_end(), llvm::SCEVNAryExpr::operands(), RHS, S, llvm::scAddExpr, llvm::scAddRecExpr, llvm::scMulExpr, setFlags(), StrengthenNoWrapFlags(), llvm::APInt::ule(), X, and Y.

Referenced by applyLoopGuards(), llvm::calculateUpperBound(), llvm::LoopVectorizationCostModel::computeMaxVF(), countToEliminateCompares(), createNodeForSelectViaUMinSeq(), llvm::SCEVAddRecExpr::evaluateAtIteration(), ExtractImmediate(), ExtractSymbol(), FactorOutConstant(), genLoopLimit(), getAddExpr(), getConstantMaxTripCountFromArray(), getExactSDiv(), getExtendAddRecStart(), getGEPExpr(), getLosslessPtrToIntExpr(), getMinusSCEV(), getMulExpr(), getNewAlignment(), llvm::InnerLoopVectorizer::getOrCreateTripCount(), llvm::SCEVAddRecExpr::getPostIncExpr(), getPreStartForExtend(), getSignExtendExpr(), getTripCount(), getTripCountFromExitCount(), getTruncateExpr(), getUDivCeilSCEV(), getUDivExpr(), getZeroExtendExpr(), llvm::RuntimePointerChecking::insert(), llvm::ARMTTIImpl::isHardwareLoopProfitable(), IsIncrementNSW(), IsIncrementNUW(), isSafeDecreasingBound(), isSafeIncreasingBound(), removePointerBase(), SimplifyAddOperands(), SimplifyICmpOperands(), llvm::UnrollRuntimeLoopRemainder(), llvm::SCEVDivision::visitAddExpr(), llvm::SCEVRewriteVisitor< SCEVLoopGuardRewriter >::visitAddExpr(), and willNotOverflow().

getAddRecExpr() [1/3]

const SCEV * ScalarEvolution::getAddRecExpr	(	const SCEV *	Start,
		const SCEV *	Step,
		const Loop *	L,
		SCEV::NoWrapFlags	Flags
	)

Get an add recurrence expression for the specified loop.

Simplify the expression as much as possible.

Definition at line 3575 of file ScalarEvolution.cpp.

References llvm::SCEV::FlagNW, maskFlags(), and Operands.

Referenced by CollectSubexprs(), DoInitialMatch(), ExtractImmediate(), ExtractSymbol(), FactorOutConstant(), getAddExpr(), getAddRecExpr(), getAnyExtendExpr(), getExactSDiv(), getMulExpr(), llvm::SCEVAddRecExpr::getNumIterationsInRange(), llvm::SCEVAddRecExpr::getPostIncExpr(), getPreStartForExtend(), getSignExtendExpr(), llvm::SCEVAddRecExpr::getStepRecurrence(), getTruncateExpr(), getUDivExpr(), getZeroExtendExpr(), isLoopBackedgeGuardedByCond(), removePointerBase(), SplitAddRecs(), llvm::SCEVDivision::visitAddRecExpr(), llvm::SCEVRewriteVisitor< SCEVLoopGuardRewriter >::visitAddRecExpr(), and llvm::SCEVLoopAddRecRewriter::visitAddRecExpr().

getAddRecExpr() [2/3]

const SCEV* llvm::ScalarEvolution::getAddRecExpr ( const SmallVectorImpl< const SCEV * > &  Operands, const Loop *  L, SCEV::NoWrapFlags  Flags  )

inline

Definition at line 603 of file ScalarEvolution.h.

References getAddRecExpr(), and Operands.

getAddRecExpr() [3/3]

const SCEV * ScalarEvolution::getAddRecExpr	(	SmallVectorImpl< const SCEV * > &	Operands,
		const Loop *	L,
		SCEV::NoWrapFlags	Flags
	)

Get an add recurrence expression for the specified loop.

Simplify the expression as much as possible.

Definition at line 3593 of file ScalarEvolution.cpp.

References llvm::all_of(), assert(), llvm::LoopBase< BlockT, LoopT >::contains(), llvm::DominatorTree::dominates(), llvm::numbers::e, llvm::SCEV::FlagAnyWrap, llvm::SCEV::FlagNW, getAddRecExpr(), getEffectiveSCEVType(), llvm::LoopBase< BlockT, LoopT >::getHeader(), llvm::LoopBase< BlockT, LoopT >::getLoopDepth(), llvm::Intrinsic::getType(), i, isLoopInvariant(), maskFlags(), Operands, llvm::scAddRecExpr, and StrengthenNoWrapFlags().

getAnyExtendExpr()

const SCEV * ScalarEvolution::getAnyExtendExpr	(	const SCEV *	Op,
		Type *	Ty
	)

getAnyExtendExpr - Return a SCEV for the given operand extended with unspecified bits out to the given type.

Definition at line 2151 of file ScalarEvolution.cpp.

References assert(), llvm::SCEV::FlagNW, getAddRecExpr(), getEffectiveSCEVType(), getSignExtendExpr(), getTruncateOrNoop(), llvm::SCEV::getType(), getTypeSizeInBits(), getZeroExtendExpr(), isSCEVable(), and llvm::PPCISD::SC.

Referenced by getAddExpr(), and getNoopOrAnyExtend().

getBackedgeTakenCount()

const SCEV * ScalarEvolution::getBackedgeTakenCount	(	const Loop *	L,
		ExitCountKind	Kind = Exact
	)

If the specified loop has a predictable backedge-taken count, return it, otherwise return a SCEVCouldNotCompute object.

The backedge-taken count is the number of times the loop header will be branched to from within the loop, assuming there are no abnormal exists like exception throws. This is one less than the trip count of the loop, since it doesn't count the first iteration, when the header is branched to from outside the loop.

Note that it is not valid to call this method on a loop without a loop-invariant backedge-taken count (see hasLoopInvariantBackedgeTakenCount).

Definition at line 7900 of file ScalarEvolution.cpp.

References ConstantMaximum, Exact, llvm_unreachable, and SymbolicMaximum.

Referenced by breakBackedgeIfNotTaken(), computeTripCount(), getConstantMaxBackedgeTakenCount(), getPreStartForExtend(), getSmallConstantTripCount(), getSymbolicMaxBackedgeTakenCount(), hasLoopInvariantBackedgeTakenCount(), llvm::ARMTTIImpl::isHardwareLoopProfitable(), llvm::IVUsers::print(), PrintLoopInfo(), verify(), and verifyTripCount().

getBlockDisposition()

ScalarEvolution::BlockDisposition ScalarEvolution::getBlockDisposition	(	const SCEV *	S,
		const BasicBlock *	BB
	)

Return the "disposition" of the given SCEV with respect to the given block.

Definition at line 13248 of file ScalarEvolution.cpp.

References BB, D, DoesNotDominateBlock, llvm::reverse(), and S.

Referenced by dominates(), and properlyDominates().

getCastExpr()

const SCEV * ScalarEvolution::getCastExpr	(	SCEVTypes	Kind,
		const SCEV *	Op,
		Type *	Ty
	)

Definition at line 2133 of file ScalarEvolution.cpp.

References getPtrToIntExpr(), getSignExtendExpr(), getTruncateExpr(), getZeroExtendExpr(), llvm_unreachable, llvm::scPtrToInt, llvm::scSignExtend, llvm::scTruncate, and llvm::scZeroExtend.

getComparePredicate()

const SCEVPredicate * ScalarEvolution::getComparePredicate	(	ICmpInst::Predicate	Pred,
		const SCEV *	LHS,
		const SCEV *	RHS
	)

Definition at line 13801 of file ScalarEvolution.cpp.

References assert(), llvm::Value::getType(), LHS, llvm::SCEVPredicate::P_Compare, RHS, and S.

Referenced by getEqualPredicate().

getConstant() [1/3]

const SCEV * ScalarEvolution::getConstant

(

const APInt &

Val

)

Definition at line 472 of file ScalarEvolution.cpp.

References llvm::ConstantInt::get(), getConstant(), and getContext().

getConstant() [2/3]

const SCEV * ScalarEvolution::getConstant

(

ConstantInt *

V

)

Definition at line 461 of file ScalarEvolution.cpp.

References S, and llvm::scConstant.

Referenced by applyLoopGuards(), BinomialCoefficient(), llvm::calculateUpperBound(), llvm::cannotBeMaxInLoop(), llvm::cannotBeMinInLoop(), CollectSubexprs(), llvm::LoopVectorizationCostModel::computeMaxVF(), llvm::IndexedReference::computeRefCost(), computeTripCount(), countToEliminateCompares(), DoInitialMatch(), EvaluateConstantChrecAtConstant(), ExtractImmediate(), ExtractSymbol(), FactorOutConstant(), getAddExpr(), getConstant(), getConstantMaxTripCountFromArray(), getExactSDiv(), getMinMaxExpr(), getMinusOne(), getMulExpr(), getNegativeSCEV(), getNotSCEV(), getOffsetOfExpr(), getOne(), getSignedOverflowLimitForStep(), getSignExtendExpr(), getSizeOfExpr(), getStoreSizeOfExpr(), getTruncateExpr(), getUDivExactExpr(), getUDivExpr(), getUnsignedOverflowLimitForStep(), getZero(), getZeroExtendExpr(), llvm::InductionDescriptor::isInductionPHI(), isSafeDecreasingBound(), isSafeDependenceDistance(), isSafeIncreasingBound(), SimplifyAddOperands(), SimplifyICmpOperands(), SolveLinEquationWithOverflow(), SplitAddRecs(), llvm::UnrolledInstAnalyzer::UnrolledInstAnalyzer(), llvm::UnrollRuntimeLoopRemainder(), verify(), and llvm::SCEVDivision::visitConstant().

getConstant() [3/3]

const SCEV * ScalarEvolution::getConstant	(	Type *	Ty,
		uint64_t	V,
		bool	isSigned = false
	)

Definition at line 477 of file ScalarEvolution.cpp.

References llvm::ConstantInt::get(), getConstant(), and getEffectiveSCEVType().

getConstantMaxBackedgeTakenCount()

const SCEV* llvm::ScalarEvolution::getConstantMaxBackedgeTakenCount ( const Loop *  L )

inline

When successful, this returns a SCEVConstant that is greater than or equal to (i.e.

a "conservative over-approximation") of the value returend by getBackedgeTakenCount. If such a value cannot be computed, it returns the SCEVCouldNotCompute object.

Definition at line 887 of file ScalarEvolution.h.

References ConstantMaximum, and getBackedgeTakenCount().

Referenced by breakBackedgeIfNotTaken(), getSignExtendExpr(), getSmallConstantMaxTripCount(), getZeroExtendExpr(), isLoopDead(), mustBeFiniteCountedLoop(), and PrintLoopInfo().

getConstantMaxTripCountFromArray()

const SCEV * ScalarEvolution::getConstantMaxTripCountFromArray

(

const Loop *

L

)

Returns the upper bound of the loop trip count infered from array size.

Can not access bytes starting outside the statically allocated size without being immediate UB. Returns SCEVCouldNotCompute if the trip count could not inferred from array accesses.

Definition at line 7697 of file ScalarEvolution.cpp.

References assert(), BB, llvm::LoopBase< BlockT, LoopT >::contains(), DL, llvm::DominatorTree::dominates(), GEP, getAddExpr(), llvm::AllocaInst::getAllocatedType(), llvm::AllocaInst::getArraySize(), llvm::LoopBase< BlockT, LoopT >::getBlocks(), getConstant(), getCouldNotCompute(), getDataLayout(), getElementSize(), llvm::LoopBase< BlockT, LoopT >::getExitingBlock(), llvm::getLoadStorePointerOperand(), llvm::LoopBase< BlockT, LoopT >::getLoopLatch(), getOne(), llvm::Instruction::getParent(), getPointerBase(), getSCEV(), llvm::SCEVAddRecExpr::getStart(), llvm::SCEVAddRecExpr::getStepRecurrence(), llvm::SCEV::getType(), getUDivCeilSCEV(), getUMinFromMismatchedTypes(), llvm::LoopBase< BlockT, LoopT >::isInnermost(), isLoopInvariant(), llvm::Loop::isLoopSimplifyForm(), and llvm::SCEV::isZero().

getContext()

LLVMContext& llvm::ScalarEvolution::getContext ( ) const

inline

Definition at line 491 of file ScalarEvolution.h.

References F.

Referenced by BinomialCoefficient(), FactorOutConstant(), getConstant(), getMinMaxExpr(), getPreStartForExtend(), getSignExtendExpr(), getUDivExpr(), getURemExpr(), getZeroExtendExpr(), isAddRecSExtable(), isAddSExtable(), isMulSExtable(), SimplifyICmpOperands(), SolveQuadraticAddRecExact(), and SolveQuadraticAddRecRange().

getCouldNotCompute()

const SCEV * ScalarEvolution::getCouldNotCompute

(

)

Definition at line 4339 of file ScalarEvolution.cpp.

Referenced by BinomialCoefficient(), getConstantMaxTripCountFromArray(), getLosslessPtrToIntExpr(), getMinAnalyzeableBackedgeTakenCount(), getMinusSCEV(), llvm::SCEVAddRecExpr::getNumIterationsInRange(), getSmallConstantTripMultiple(), getTripCountFromExitCount(), isKnownViaInduction(), isLoopBackedgeGuardedByCond(), SolveLinEquationWithOverflow(), SplitIntoInitAndPostInc(), and verify().

getDataLayout()

const DataLayout& llvm::ScalarEvolution::getDataLayout ( ) const

inline

Return the DataLayout associated with the module this SCEV instance is operating on.

Definition at line 1157 of file ScalarEvolution.h.

References llvm::Module::getDataLayout(), and llvm::GlobalValue::getParent().

Referenced by CreateStepValue(), getConstantMaxTripCountFromArray(), getEffectiveSCEVType(), getLosslessPtrToIntExpr(), getOffsetOfExpr(), getSizeOfExpr(), getStoreSizeOfExpr(), getTypeSizeInBits(), and llvm::simplifyLoopIVs().

getEffectiveSCEVType()

Type * ScalarEvolution::getEffectiveSCEVType

(

Type *

Ty

)

const

Return a type with the same bitwidth as the given type and which represents how SCEV will treat the given type, for which isSCEVable must return true.

For pointer types, this is the pointer-sized integer type.

For pointer types, this is the pointer index sized integer type.

Definition at line 4309 of file ScalarEvolution.cpp.

References assert(), getDataLayout(), llvm::DataLayout::getIndexType(), llvm::Type::isIntegerTy(), llvm::Type::isPointerTy(), and isSCEVable().

Referenced by canBeCheaplyTransformed(), canComputePointerDiff(), DoInitialMatch(), genLoopLimit(), getAddExpr(), getAddRecExpr(), getAnyExtendExpr(), getConstant(), getElementSize(), getGEPExpr(), getLosslessPtrToIntExpr(), getMinMaxExpr(), getNegativeSCEV(), getNewAlignment(), getNotSCEV(), getSequentialMinMaxExpr(), getSignExtendExpr(), getTruncateExpr(), getURemExpr(), getZeroExtendExpr(), isExistingPhi(), and visitIVCast().

getElementSize()

const SCEV * ScalarEvolution::getElementSize

(

Instruction *

Inst

)

Return the size of an element read or written by Inst.

Definition at line 12833 of file ScalarEvolution.cpp.

References getEffectiveSCEVType(), getSizeOfExpr(), llvm::PointerType::getUnqual(), llvm::SPII::Load, and llvm::SPII::Store.

Referenced by getConstantMaxTripCountFromArray().

getEqualPredicate()

const SCEVPredicate * ScalarEvolution::getEqualPredicate	(	const SCEV *	LHS,
		const SCEV *	RHS
	)

Definition at line 13795 of file ScalarEvolution.cpp.

References getComparePredicate(), llvm::CmpInst::ICMP_EQ, LHS, and RHS.

Referenced by llvm::PredicatedScalarEvolution::areAddRecsEqualWithPreds(), and llvm::replaceSymbolicStrideSCEV().

getExitCount()

const SCEV * ScalarEvolution::getExitCount	(	const Loop *	L,
		const BasicBlock *	ExitingBlock,
		ExitCountKind	Kind = Exact
	)

Return the number of times the backedge executes before the given exit would be taken; if not exactly computable, return SCEVCouldNotCompute.

For a single exit loop, this value is equivelent to the result of getBackedgeTakenCount. The loop is guaranteed to exit (via some exit) before the backedge is executed (ExitCount + 1) times. Note that there is no guarantee about which exit is taken on the exiting iteration.

Definition at line 7881 of file ScalarEvolution.cpp.

References ConstantMaximum, Exact, llvm_unreachable, and SymbolicMaximum.

Referenced by llvm::calculateUpperBound(), getMinAnalyzeableBackedgeTakenCount(), getSmallConstantTripCount(), getSmallConstantTripMultiple(), llvm::hasIterationCountInvariantInParent(), llvm::HardwareLoopInfo::isHardwareLoopCandidate(), mustBeFiniteCountedLoop(), PrintLoopInfo(), llvm::rewriteLoopExitValues(), and llvm::UnrollRuntimeLoopRemainder().

getGEPExpr()

const SCEV * ScalarEvolution::getGEPExpr	(	GEPOperator *	GEP,
		const SmallVectorImpl< const SCEV * > &	IndexExprs
	)

Returns an expression for a GEP.

GEP The GEP. The indices contained in the GEP itself are ignored, instead we use IndexExprs. IndexExprs The expressions for the indices.

Definition at line 3670 of file ScalarEvolution.cpp.

References assert(), llvm::SCEV::FlagAnyWrap, llvm::SCEV::FlagNSW, llvm::SCEV::FlagNUW, GEP, getAddExpr(), getEffectiveSCEVType(), getMulExpr(), getOffsetOfExpr(), getSCEV(), getSizeOfExpr(), getTruncateOrSignExtend(), llvm::SCEV::getType(), llvm::GetElementPtrInst::getTypeAtIndex(), llvm::ConstantInt::getValue(), llvm::APInt::getZExtValue(), and isKnownNonNegative().

getLoopDisposition()

ScalarEvolution::LoopDisposition ScalarEvolution::getLoopDisposition	(	const SCEV *	S,
		const Loop *	L
	)

Return the "disposition" of the given SCEV with respect to the given loop.

Definition at line 13139 of file ScalarEvolution.cpp.

References D, LoopVariant, llvm::reverse(), and S.

Referenced by hasComputableLoopEvolution(), llvm::hasIterationCountInvariantInParent(), isLoopInvariant(), and print().

getLoopInvariantExitCondDuringFirstIterations()

Optional< ScalarEvolution::LoopInvariantPredicate > ScalarEvolution::getLoopInvariantExitCondDuringFirstIterations	(	ICmpInst::Predicate	Pred,
		const SCEV *	LHS,
		const SCEV *	RHS,
		const Loop *	L,
		const Instruction *	CtxI,
		const SCEV *	MaxIter
	)

If the result of the predicate LHS Pred RHS is loop invariant with respect to L at given Context during at least first MaxIter iterations, return a LoopInvariantPredicate with LHS and RHS being invariants, available at L's entry.

Otherwise, return None. The predicate should be the loop's exit condition.

Definition at line 10574 of file ScalarEvolution.cpp.

References llvm::SCEVAddRecExpr::evaluateAtIteration(), llvm::SCEVAddRecExpr::getLoop(), getNegativeSCEV(), getOne(), llvm::SCEVAddRecExpr::getStart(), llvm::SCEVAddRecExpr::getStepRecurrence(), llvm::CmpInst::getSwappedPredicate(), llvm::SCEV::getType(), llvm::SCEVAddRecExpr::getType(), llvm::CmpInst::ICMP_SLE, llvm::CmpInst::ICMP_ULE, isKnownPredicateAt(), isLoopBackedgeGuardedByCond(), isLoopInvariant(), llvm::ICmpInst::isRelational(), llvm::CmpInst::isSigned(), LHS, llvm::None, RHS, and std::swap().

Referenced by optimizeLoopExitWithUnknownExitCount().

getLoopInvariantPredicate()

Optional< ScalarEvolution::LoopInvariantPredicate > ScalarEvolution::getLoopInvariantPredicate	(	ICmpInst::Predicate	Pred,
		const SCEV *	LHS,
		const SCEV *	RHS,
		const Loop *	L
	)

If the result of the predicate LHS Pred RHS is loop invariant with respect to L, return a LoopInvariantPredicate with LHS and RHS being invariants, available at L's entry.

Otherwise, return None.

Definition at line 10527 of file ScalarEvolution.cpp.

References llvm::CmpInst::getInversePredicate(), llvm::SCEVAddRecExpr::getLoop(), getMonotonicPredicateType(), llvm::SCEVAddRecExpr::getStart(), llvm::CmpInst::getSwappedPredicate(), isLoopBackedgeGuardedByCond(), isLoopInvariant(), LHS, MonotonicallyIncreasing, llvm::None, P, RHS, and std::swap().

getLosslessPtrToIntExpr()

const SCEV * ScalarEvolution::getLosslessPtrToIntExpr	(	const SCEV *	Op,
		unsigned	Depth = 0
	)

The SCEVPtrToIntSinkingRewriter takes a scalar evolution expression, which computes a pointer-typed value, and rewrites the whole expression tree so that all the computations are done on integers, and the only pointer-typed operands in the expression are SCEVUnknown.

Definition at line 1069 of file ScalarEvolution.cpp.

References assert(), llvm::sampleprof::Base, llvm::Depth, getAddExpr(), getCouldNotCompute(), getDataLayout(), getEffectiveSCEVType(), llvm::DataLayout::getIntPtrType(), getLosslessPtrToIntExpr(), getMulExpr(), llvm::SCEVNAryExpr::getNoWrapFlags(), llvm::SCEV::getType(), llvm::SCEVUnknown::getType(), getTypeSizeInBits(), getZero(), llvm::Type::isIntegerTy(), llvm::Type::isPointerTy(), Operands, llvm::SCEVNAryExpr::operands(), registerUser(), rewrite(), Rewriter, S, and llvm::scPtrToInt.

Referenced by getLosslessPtrToIntExpr(), and getPtrToIntExpr().

getMinMaxExpr()

const SCEV * ScalarEvolution::getMinMaxExpr	(	SCEVTypes	Kind,
		SmallVectorImpl< const SCEV * > &	Operands
	)

Definition at line 3759 of file ScalarEvolution.cpp.

References llvm::BumpPtrAllocatorImpl< AllocatorT, SlabSize, SizeThreshold, GrowthDelay >::Allocate(), llvm::SmallVectorImpl< T >::append(), assert(), llvm::numbers::e, llvm::SmallVectorImpl< T >::erase(), llvm::ConstantInt::get(), getConstant(), getContext(), getEffectiveSCEVType(), llvm::Intrinsic::getType(), GroupByComplexity(), i, llvm::CmpInst::ICMP_SGE, llvm::CmpInst::ICMP_SLE, llvm::CmpInst::ICMP_UGE, llvm::CmpInst::ICMP_ULE, LHS, llvm_unreachable, llvm::RISCVFenceField::O, llvm::SCEVNAryExpr::op_begin(), llvm::SCEVNAryExpr::op_end(), registerUser(), RHS, S, llvm::scSMaxExpr, llvm::scSMinExpr, llvm::scUMaxExpr, llvm::scUMinExpr, llvm::APIntOps::smax(), llvm::APIntOps::smin(), llvm::APIntOps::umax(), and llvm::APIntOps::umin().

Referenced by getNotSCEV(), getSequentialMinMaxExpr(), getSMaxExpr(), getSMinExpr(), getUMaxExpr(), and getUMinExpr().

GetMinTrailingZeros()

uint32_t ScalarEvolution::GetMinTrailingZeros

(

const SCEV *

S

)

Determine the minimum number of zero bits that S is guaranteed to end in (at every loop iteration).

It is, at the same time, the minimum number of times S is divisible by 2. For example, given {4,+,8} it returns 2. If S is guaranteed to be 0, it returns the bitwidth of S.

Definition at line 6251 of file ScalarEvolution.cpp.

References assert(), I, and S.

Referenced by extractConstantWithoutWrapping(), getSmallConstantTripMultiple(), getTruncateExpr(), and SolveLinEquationWithOverflow().

getMinusOne()

const SCEV* llvm::ScalarEvolution::getMinusOne ( Type *  Ty )

inline

Return a SCEV for the constant -1 of a specific type.

Definition at line 648 of file ScalarEvolution.h.

References getConstant().

Referenced by getNegativeSCEV(), getNotSCEV(), and optimizeLoopExitWithUnknownExitCount().

getMinusSCEV()

const SCEV * ScalarEvolution::getMinusSCEV	(	const SCEV *	LHS,
		const SCEV *	RHS,
		SCEV::NoWrapFlags	Flags = SCEV::FlagAnyWrap,
		unsigned	Depth = 0
	)

Return LHS-RHS.

Minus is represented in SCEV as A+B*-1.

If the LHS and RHS are pointers which don't share a common base (according to getPointerBase()), this returns a SCEVCouldNotCompute. To compute the difference between two unrelated pointers, you can explicitly convert the arguments using getPtrToIntExpr(), for pointer types that support it.

Definition at line 4523 of file ScalarEvolution.cpp.

References llvm::Depth, llvm::SCEV::FlagAnyWrap, llvm::SCEV::FlagNSW, getAddExpr(), getCouldNotCompute(), getNegativeSCEV(), getPointerBase(), getSignedRangeMin(), llvm::Value::getType(), getZero(), hasFlags(), isKnownNonNegative(), llvm::APInt::isMinSignedValue(), llvm::Type::isPointerTy(), LHS, removePointerBase(), and RHS.

Referenced by llvm::SCEVAAResult::alias(), applyLoopGuards(), BinomialCoefficient(), canBeCheaplyTransformed(), createNodeForSelectViaUMinSeq(), getMinFromExprs(), getNewAlignment(), getNotSCEV(), llvm::getPointersDiff(), getStartForNegStride(), getUDivCeilSCEV(), getURemExpr(), llvm::IndexedReference::hasSpacialReuse(), isSafeDecreasingBound(), isSafeDependenceDistance(), isSafeIncreasingBound(), optimizeLoopExitWithUnknownExitCount(), verify(), llvm::SCEVDivision::visitMulExpr(), and willNotOverflow().

getMonotonicPredicateType()

Optional< ScalarEvolution::MonotonicPredicateType > ScalarEvolution::getMonotonicPredicateType	(	const SCEVAddRecExpr *	LHS,
		ICmpInst::Predicate	Pred
	)

If, for all loop invariant X, the predicate "LHS `Pred` X" is monotonically increasing or decreasing, returns Some(MonotonicallyIncreasing) and Some(MonotonicallyDecreasing) respectively.

If we could not prove either of these facts, returns None.

Definition at line 10462 of file ScalarEvolution.cpp.

References assert(), llvm::CmpInst::getSwappedPredicate(), and LHS.

Referenced by countToEliminateCompares(), getLoopInvariantPredicate(), and isSafeToTruncateWideIVType().

getMulExpr() [1/3]

const SCEV* llvm::ScalarEvolution::getMulExpr ( const SCEV *  LHS, const SCEV *  RHS, SCEV::NoWrapFlags  Flags = SCEV::FlagAnyWrap, unsigned  Depth = 0  )

inline

Definition at line 584 of file ScalarEvolution.h.

References llvm::Depth, getMulExpr(), LHS, and RHS.

getMulExpr() [2/3]

const SCEV* llvm::ScalarEvolution::getMulExpr ( const SCEV *  Op0, const SCEV *  Op1, const SCEV *  Op2, SCEV::NoWrapFlags  Flags = SCEV::FlagAnyWrap, unsigned  Depth = 0  )

inline

Definition at line 590 of file ScalarEvolution.h.

References llvm::Depth, and getMulExpr().

getMulExpr() [3/3]

const SCEV * ScalarEvolution::getMulExpr	(	SmallVectorImpl< const SCEV * > &	Ops,
		SCEV::NoWrapFlags	Flags = SCEV::FlagAnyWrap,
		unsigned	Depth = 0
	)

Get a canonical multiply expression, or something simpler if possible.

Definition at line 3050 of file ScalarEvolution.cpp.

References llvm::SmallVectorImpl< T >::append(), assert(), Choose(), containsConstantInAddMulChain(), llvm::Depth, llvm::numbers::e, llvm::SmallVectorImpl< T >::erase(), llvm::SCEV::FlagAnyWrap, llvm::SCEV::FlagNSW, llvm::SCEV::FlagNUW, llvm::SCEV::FlagNW, getAddExpr(), getAddRecExpr(), getConstant(), llvm::SCEVAddRecExpr::getLoop(), llvm::SCEVNAryExpr::getNoWrapFlags(), llvm::SCEVNAryExpr::getNumOperands(), llvm::SCEVNAryExpr::getOperand(), llvm::Intrinsic::getType(), llvm::SCEVAddRecExpr::getType(), getTypeSizeInBits(), getZero(), GroupByComplexity(), hasHugeExpression(), i, isAvailableAtLoopEntry(), llvm::Type::isPointerTy(), LHS, maskFlags(), llvm::max(), MaxAddRecSize, MaxArithDepth, llvm::min(), Mul, MulOpsInlineThreshold, llvm::User::op_begin(), llvm::User::op_end(), Operands, llvm::SmallVectorImpl< T >::reserve(), RHS, S, llvm::scAddRecExpr, llvm::scMulExpr, StrengthenNoWrapFlags(), umul_ov(), x, y, and z.

Referenced by applyLoopGuards(), BinomialCoefficient(), CollectAddOperandsWithScales(), CollectSubexprs(), llvm::IndexedReference::computeRefCost(), DoInitialMatch(), llvm::SCEVAddRecExpr::evaluateAtIteration(), FactorOutConstant(), findArrayDimensionsRec(), getAddExpr(), getExactSDiv(), getGEPExpr(), getLosslessPtrToIntExpr(), getMulExpr(), getNegativeSCEV(), getNumBytes(), getSignExtendExpr(), getStartForNegStride(), getTruncateExpr(), getUDivExactExpr(), getUDivExpr(), getURemExpr(), getZeroExtendExpr(), isSafeDependenceDistance(), removeConstantFactors(), SolveLinEquationWithOverflow(), llvm::SCEVDivision::visitMulExpr(), llvm::SCEVRewriteVisitor< SCEVLoopGuardRewriter >::visitMulExpr(), and willNotOverflow().

getNegativeSCEV()

const SCEV * ScalarEvolution::getNegativeSCEV	(	const SCEV *	V,
		SCEV::NoWrapFlags	Flags = SCEV::FlagAnyWrap
	)

Return the SCEV object corresponding to -V.

Return a SCEV corresponding to -V = -1*V.

Definition at line 4437 of file ScalarEvolution.cpp.

References getConstant(), getEffectiveSCEVType(), getMinusOne(), getMulExpr(), llvm::ConstantExpr::getNeg(), llvm::SCEV::getType(), and llvm::AArch64CC::VC.

Referenced by llvm::IndexedReference::computeRefCost(), detectShiftUntilZeroIdiom(), getAbsExpr(), getLoopInvariantExitCondDuringFirstIterations(), getMinusSCEV(), getTripCount(), isOneDimensionalArray(), and isSafeDependenceDistance().

getNoopOrAnyExtend()

const SCEV * ScalarEvolution::getNoopOrAnyExtend	(	const SCEV *	V,
		Type *	Ty
	)

Return a SCEV corresponding to a conversion of the input value to the specified type.

If the type must be extended, it is extended with unspecified bits. The conversion must not be narrowing.

Definition at line 4622 of file ScalarEvolution.cpp.

References assert(), getAnyExtendExpr(), llvm::SCEV::getType(), getTypeSizeInBits(), and llvm::Type::isIntOrPtrTy().

Referenced by llvm::IndexedReference::computeRefCost().

getNoopOrSignExtend()

const SCEV * ScalarEvolution::getNoopOrSignExtend	(	const SCEV *	V,
		Type *	Ty
	)

Return a SCEV corresponding to a conversion of the input value to the specified type.

If the type must be extended, it is sign extended. The conversion must not be narrowing.

Definition at line 4610 of file ScalarEvolution.cpp.

References assert(), getSignExtendExpr(), llvm::SCEV::getType(), getTypeSizeInBits(), and llvm::Type::isIntOrPtrTy().

Referenced by getNewAlignment(), isSafeDependenceDistance(), and NoopOrExtend().

getNoopOrZeroExtend()

const SCEV * ScalarEvolution::getNoopOrZeroExtend	(	const SCEV *	V,
		Type *	Ty
	)

Return a SCEV corresponding to a conversion of the input value to the specified type.

If the type must be extended, it is zero extended. The conversion must not be narrowing.

Definition at line 4598 of file ScalarEvolution.cpp.

References assert(), llvm::SCEV::getType(), getTypeSizeInBits(), getZeroExtendExpr(), and llvm::Type::isIntOrPtrTy().

Referenced by llvm::InnerLoopVectorizer::getOrCreateTripCount(), getTripCountFromExitCount(), getUMaxFromMismatchedTypes(), getUMinFromMismatchedTypes(), and NoopOrExtend().

getNotSCEV()

const SCEV * ScalarEvolution::getNotSCEV

(

const SCEV *

V

)

Return the SCEV object corresponding to ~V.

Return a SCEV corresponding to ~V = -1-V.

Definition at line 4464 of file ScalarEvolution.cpp.

References assert(), getConstant(), getEffectiveSCEVType(), getMinMaxExpr(), getMinusOne(), getMinusSCEV(), llvm::ConstantExpr::getNot(), llvm::SCEV::getType(), llvm::Type::isPointerTy(), MatchNotExpr(), llvm::SCEVMinMaxExpr::negate(), and llvm::AArch64CC::VC.

Referenced by createNodeForSelectViaUMinSeq().

getOffsetOfExpr()

const SCEV * ScalarEvolution::getOffsetOfExpr	(	Type *	IntTy,
		StructType *	STy,
		unsigned	FieldNo
	)

Return an expression for offsetof on the given field with type IntTy.

Definition at line 4252 of file ScalarEvolution.cpp.

References getConstant(), and getDataLayout().

Referenced by getGEPExpr().

getOne()

const SCEV* llvm::ScalarEvolution::getOne ( Type *  Ty )

inline

Return a SCEV for the constant 1 of a specific type.

Definition at line 645 of file ScalarEvolution.h.

References getConstant().

Referenced by applyLoopGuards(), llvm::calculateUpperBound(), llvm::LoopVectorizationCostModel::computeMaxVF(), genLoopLimit(), getAddExpr(), getConstantMaxTripCountFromArray(), getLoopInvariantExitCondDuringFirstIterations(), llvm::InnerLoopVectorizer::getOrCreateTripCount(), getTripCount(), getTripCountFromExitCount(), getUDivCeilSCEV(), llvm::ARMTTIImpl::isHardwareLoopProfitable(), isLoopBackedgeGuardedByCond(), isSafeDecreasingBound(), isSafeIncreasingBound(), optimizeLoopExitWithUnknownExitCount(), and llvm::replaceSymbolicStrideSCEV().

getPointerBase()

const SCEV * ScalarEvolution::getPointerBase

(

const SCEV *

V

)

Transitively follow the chain of pointer-type operands until reaching a SCEV that does not have a single pointer operand.

This returns a SCEVUnknown pointer for well-formed pointer-type expressions, but corner cases do exist.

Definition at line 4691 of file ScalarEvolution.cpp.

References assert(), llvm::SCEV::getType(), and llvm::Type::isPointerTy().

Referenced by llvm::DependenceInfo::depends(), getConstantMaxTripCountFromArray(), getMinusSCEV(), and llvm::tryDelinearizeFixedSizeImpl().

getPredicatedBackedgeTakenCount()

const SCEV * ScalarEvolution::getPredicatedBackedgeTakenCount	(	const Loop *	L,
		SmallVector< const SCEVPredicate *, 4 > &	Predicates
	)

Similar to getBackedgeTakenCount, except it will add a set of SCEV predicates to Predicates that are required to be true in order for the answer to be correct.

Predicates can be checked with run-time checks and can be used to perform loop versioning.

Definition at line 7895 of file ScalarEvolution.cpp.

Referenced by llvm::PredicatedScalarEvolution::getBackedgeTakenCount(), and PrintLoopInfo().

getPtrToIntExpr()

const SCEV * ScalarEvolution::getPtrToIntExpr	(	const SCEV *	Op,
		Type *	Ty
	)

Definition at line 1193 of file ScalarEvolution.cpp.

References assert(), getLosslessPtrToIntExpr(), getTruncateOrZeroExtend(), and llvm::Type::isIntegerTy().

Referenced by getCastExpr(), and llvm::SCEVRewriteVisitor< SCEVLoopGuardRewriter >::visitPtrToIntExpr().

getSCEV()

const SCEV * ScalarEvolution::getSCEV

(

Value *

V

)

Return a SCEV expression for the full generality of the specified expression.

Return an existing SCEV if it exists, otherwise analyze the expression and create a new one.

Definition at line 4406 of file ScalarEvolution.cpp.

References assert(), llvm::Value::getType(), llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::insert(), isSCEVable(), S, and SCEVCallbackVH.

Referenced by llvm::RecurrenceDescriptor::AddReductionVar(), llvm::IVUsers::AddUsersIfInteresting(), llvm::SCEVAAResult::alias(), llvm::analyzeICmp(), applyLoopGuards(), canOverlap(), canTailPredicateLoop(), countToEliminateCompares(), createNodeForSelectViaUMinSeq(), DbgGatherSalvagableDVI(), DbgRewriteSalvageableDVIs(), llvm::DependenceInfo::depends(), detectShiftUntilZeroIdiom(), DoInitialMatch(), llvm::AlignmentFromAssumptionsPass::extractAlignmentInfo(), findIVOperand(), FindLoopCounter(), genLoopLimit(), llvm::PredicatedScalarEvolution::getAsAddRec(), llvm::Loop::LoopBounds::getBounds(), getBoundsCheckCond(), getConstantMaxTripCountFromArray(), getFalkorUnrollingPreferences(), getGEPExpr(), llvm::getIndexExpressionsFromGEP(), GetInductionVariable(), getNewAlignment(), llvm::getPointersDiff(), llvm::IVUsers::getReplacementExpr(), llvm::PredicatedScalarEvolution::getSCEV(), getSCEVAtScope(), llvm::DependenceInfo::getSplitIteration(), getStrengthenedNoWrapFlagsFromBinOp(), llvm::getStrideFromPointer(), llvm::isDereferenceableAndAlignedInLoop(), isExistingPhi(), isHighCostExpansion(), llvm::InductionDescriptor::isInductionPHI(), llvm::LoopVectorizationLegality::isInvariantAddressOfReduction(), isLoopCounter(), isProfitableChain(), isSimpleIVUser(), llvm::LoopAccessInfo::isUniform(), print(), llvm::PredicatedScalarEvolution::print(), llvm::AlignmentFromAssumptionsPass::processAssumption(), llvm::replaceSymbolicStrideSCEV(), llvm::rewriteLoopExitValues(), llvm::splitLoopBound(), llvm::storeToSameAddress(), llvm::stripGetElementPtr(), verify(), verifyTripCount(), and llvm::VPlanTransforms::VPInstructionsToVPRecipes().

getSCEVAtScope() [1/2]

const SCEV * ScalarEvolution::getSCEVAtScope	(	const SCEV *	S,
		const Loop *	L
	)

Return a SCEV expression for the specified value at the specified scope in the program.

The L value specifies a loop nest to evaluate the expression at, where null is the top-level or a specified loop is immediately inside of the loop.

This method can be used to compute the exit value for a variable defined in a loop by querying what the value will hold in the parent loop.

In the case that a relevant loop exit value cannot be computed, the original value V is returned.

Definition at line 9236 of file ScalarEvolution.cpp.

References llvm::AArch64CC::LS, and llvm::reverse().

Referenced by computeUnrollAndJamCount(), getSCEVAtScope(), isInteresting(), optimizeLoopExitWithUnknownExitCount(), print(), and llvm::rewriteLoopExitValues().

getSCEVAtScope() [2/2]

const SCEV * ScalarEvolution::getSCEVAtScope	(	Value *	V,
		const Loop *	L
	)

This is a convenience function which does getSCEVAtScope(getSCEV(V), L).

Definition at line 9589 of file ScalarEvolution.cpp.

References getSCEV(), and getSCEVAtScope().

getSequentialMinMaxExpr()

const SCEV * ScalarEvolution::getSequentialMinMaxExpr	(	SCEVTypes	Kind,
		SmallVectorImpl< const SCEV * > &	Operands
	)

Definition at line 4073 of file ScalarEvolution.cpp.

References llvm::BumpPtrAllocatorImpl< AllocatorT, SlabSize, SizeThreshold, GrowthDelay >::Allocate(), assert(), llvm::numbers::e, llvm::SmallVectorImpl< T >::erase(), getEffectiveSCEVType(), llvm::SCEVSequentialMinMaxExpr::getEquivalentNonSequentialSCEVType(), getMinMaxExpr(), llvm::Intrinsic::getType(), getZero(), i, llvm::CmpInst::ICMP_NE, llvm::CmpInst::ICMP_ULE, llvm::impliesPoison(), llvm::SmallVectorImpl< T >::insert(), llvm_unreachable, llvm::RISCVFenceField::O, registerUser(), S, and llvm::scSequentialUMinExpr.

Referenced by getUMinExpr().

getSignedRange()

ConstantRange llvm::ScalarEvolution::getSignedRange ( const SCEV *  S )

inline

Determine the signed range for a particular SCEV.

NOTE: This returns a copy of the reference returned by getRangeRef.

Definition at line 962 of file ScalarEvolution.h.

References S.

Referenced by getSignExtendExpr(), print(), and StrengthenNoWrapFlags().

getSignedRangeMax()

APInt llvm::ScalarEvolution::getSignedRangeMax ( const SCEV *  S )

inline

Determine the max of the signed range for a particular SCEV.

Definition at line 972 of file ScalarEvolution.h.

References llvm::ConstantRange::getSignedMax(), and S.

Referenced by getSignedOverflowLimitForStep(), isKnownNegative(), isKnownNonPositive(), and SimplifyICmpOperands().

getSignedRangeMin()

APInt llvm::ScalarEvolution::getSignedRangeMin ( const SCEV *  S )

inline

Determine the min of the signed range for a particular SCEV.

Definition at line 967 of file ScalarEvolution.h.

References llvm::ConstantRange::getSignedMin(), and S.

Referenced by getMinusSCEV(), getSignedOverflowLimitForStep(), getZeroExtendExpr(), isKnownNonNegative(), isKnownPositive(), and SimplifyICmpOperands().

getSignExtendExpr()

const SCEV * ScalarEvolution::getSignExtendExpr	(	const SCEV *	Op,
		Type *	Ty,
		unsigned	Depth = 0
	)

Definition at line 1896 of file ScalarEvolution.cpp.

References assert(), llvm::BitWidth, llvm::ConstantRange::contains(), D, llvm::Depth, extractConstantWithoutWrapping(), llvm::SCEV::FlagAnyWrap, llvm::SCEV::FlagNSW, llvm::SCEV::FlagNUW, llvm::SCEV::FlagNW, llvm::IntegerType::get(), getAddExpr(), getAddRecExpr(), getConstant(), getConstantMaxBackedgeTakenCount(), getContext(), getEffectiveSCEVType(), getMulExpr(), llvm::ConstantExpr::getSExt(), getSignedRange(), getTruncateOrSignExtend(), getTruncateOrZeroExtend(), llvm::SCEV::getType(), getTypeSizeInBits(), getZeroExtendExpr(), isKnownNonNegative(), isSCEVable(), MaxCastDepth, registerUser(), S, llvm::PPCISD::SC, llvm::scSignExtend, setNoWrapFlags(), llvm::ConstantRange::sextOrTrunc(), llvm::ConstantRange::signExtend(), llvm::X86AS::SS, llvm::ARM_MB::ST, llvm::ConstantRange::truncate(), and X.

Referenced by getAnyExtendExpr(), getCastExpr(), getNoopOrSignExtend(), getTruncateOrSignExtend(), getZeroExtendExpr(), isAddRecSExtable(), isAddSExtable(), IsIncrementNSW(), isMulSExtable(), llvm::SCEVRewriteVisitor< SCEVLoopGuardRewriter >::visitSignExtendExpr(), and willNotOverflow().

getSizeOfExpr()

const SCEV * ScalarEvolution::getSizeOfExpr	(	Type *	IntTy,
		Type *	AllocTy
	)

Return an expression for the alloc size of AllocTy that is type IntTy.

Definition at line 4234 of file ScalarEvolution.cpp.

References getConstant(), getDataLayout(), and getSizeOfScalableVectorExpr().

Referenced by getElementSize(), and getGEPExpr().

getSizeOfScalableVectorExpr()

const SCEV * ScalarEvolution::getSizeOfScalableVectorExpr	(	Type *	IntTy,
		ScalableVectorType *	ScalableTy
	)

Return an expression for sizeof ScalableTy that is type IntTy, where ScalableTy is a scalable vector type.

Definition at line 4223 of file ScalarEvolution.cpp.

References GEP, llvm::ConstantInt::get(), llvm::ConstantExpr::getGetElementPtr(), llvm::Constant::getNullValue(), llvm::Type::getPointerTo(), llvm::ConstantExpr::getPtrToInt(), and getUnknown().

Referenced by getSizeOfExpr(), and getStoreSizeOfExpr().

getSmallConstantMaxTripCount()

unsigned ScalarEvolution::getSmallConstantMaxTripCount

(

const Loop *

L

)

Returns the upper bound of the loop trip count as a normal unsigned value.

Returns 0 if the trip count is unknown or not constant.

Definition at line 7691 of file ScalarEvolution.cpp.

References getConstantMaxBackedgeTakenCount(), and getConstantTripCount().

Referenced by llvm::HexagonTTIImpl::getPeelingPreferences(), getSmallBestKnownTC(), llvm::isDereferenceableAndAlignedInLoop(), llvm::LoopVectorizationCostModel::isMoreProfitable(), tryToUnrollLoop(), and llvm::UnrollLoop().

getSmallConstantTripCount() [1/2]

unsigned ScalarEvolution::getSmallConstantTripCount

(

const Loop *

L

)

Returns the exact trip count of the loop if we can compute it, and the result is a small constant.

'0' is used to represent an unknown or non-constant trip count. Note that a trip count is simply one more than the backedge taken count for the loop.

Definition at line 7675 of file ScalarEvolution.cpp.

References Exact, getBackedgeTakenCount(), and getConstantTripCount().

Referenced by llvm::CacheCost::CacheCost(), llvm::LoopVectorizationCostModel::computeMaxVF(), llvm::HexagonTTIImpl::getPeelingPreferences(), getSmallBestKnownTC(), llvm::PPCTTIImpl::isHardwareLoopProfitable(), tryToUnrollAndJamLoop(), tryToUnrollLoop(), and llvm::UnrollLoop().

getSmallConstantTripCount() [2/2]

unsigned ScalarEvolution::getSmallConstantTripCount	(	const Loop *	L,
		const BasicBlock *	ExitingBlock
	)

Return the exact trip count for this loop if we exit through ExitingBlock.

'0' is used to represent an unknown or non-constant trip count. Note that a trip count is simply one more than the backedge taken count for the same exit. This "trip count" assumes that control exits via ExitingBlock. More precisely, it is the number of times that control will reach ExitingBlock before taking the branch. For loops with multiple exits, it may not be the number times that the loop header executes if the loop exits prematurely via another branch.

Definition at line 7681 of file ScalarEvolution.cpp.

References assert(), getConstantTripCount(), getExitCount(), and llvm::LoopBase< BlockT, LoopT >::isLoopExiting().

getSmallConstantTripMultiple() [1/3]

unsigned ScalarEvolution::getSmallConstantTripMultiple

(

const Loop *

L

)

Returns the largest constant divisor of the trip count of the loop.

Will return 1 if no trip count could be computed, or if a divisor could not be found.

Definition at line 7817 of file ScalarEvolution.cpp.

References llvm::LoopBase< BlockT, LoopT >::getExitingBlocks(), getSmallConstantTripMultiple(), llvm::GreatestCommonDivisor64(), llvm::None, and llvm::Optional< T >::value_or().

getSmallConstantTripMultiple() [2/3]

unsigned ScalarEvolution::getSmallConstantTripMultiple	(	const Loop *	L,
		const BasicBlock *	ExitingBlock
	)

Returns the largest constant divisor of the trip count of this loop as a normal unsigned value, if possible.

This means that the actual trip count is always a multiple of the returned value (don't forget the trip count could very well be zero as well!). As explained in the comments for getSmallConstantTripCount, this assumes that control exits the loop via ExitingBlock.

This means that the actual trip count is always a multiple of the returned value (don't forget the trip count could very well be zero as well!).

Returns 1 if the trip count is unknown or not guaranteed to be the multiple of a constant (which is also the case if the trip count is simply constant, use getSmallConstantTripCount for that case), Will also return 1 if the trip count is very large (>= 2^32).

As explained in the comments for getSmallConstantTripCount, this assumes that control exits the loop via ExitingBlock.

Definition at line 7872 of file ScalarEvolution.cpp.

References assert(), getExitCount(), getSmallConstantTripMultiple(), and llvm::LoopBase< BlockT, LoopT >::isLoopExiting().

getSmallConstantTripMultiple() [3/3]

unsigned ScalarEvolution::getSmallConstantTripMultiple	(	const Loop *	L,
		const SCEV *	ExitCount
	)

Returns the largest constant divisor of the trip count as a normal unsigned value, if possible.

This means that the actual trip count is always a multiple of the returned value. Returns 1 if the trip count is unknown or not guaranteed to be the multiple of a constant., Will also return 1 if the trip count is very large (>= 2^32). Note that the argument is an exit count for loop L, NOT a trip count.

Definition at line 7831 of file ScalarEvolution.cpp.

References applyLoopGuards(), getCouldNotCompute(), GetMinTrailingZeros(), getTripCountFromExitCount(), llvm::SCEVConstant::getValue(), and llvm::min().

Referenced by getSmallConstantTripMultiple(), PrintLoopInfo(), tryToUnrollAndJamLoop(), tryToUnrollLoop(), and llvm::UnrollLoop().

getSMaxExpr() [1/2]

const SCEV * ScalarEvolution::getSMaxExpr	(	const SCEV *	LHS,
		const SCEV *	RHS
	)

Definition at line 4182 of file ScalarEvolution.cpp.

References LHS, and RHS.

Referenced by applyLoopGuards(), getAbsExpr(), IntersectSignedRange(), and llvm::SCEVRewriteVisitor< SCEVLoopGuardRewriter >::visitSMaxExpr().

getSMaxExpr() [2/2]

const SCEV * ScalarEvolution::getSMaxExpr

(

SmallVectorImpl< const SCEV * > &

Operands

)

Definition at line 4187 of file ScalarEvolution.cpp.

References getMinMaxExpr(), and llvm::scSMaxExpr.

getSMinExpr() [1/2]

const SCEV * ScalarEvolution::getSMinExpr	(	const SCEV *	LHS,
		const SCEV *	RHS
	)

Definition at line 4200 of file ScalarEvolution.cpp.

References LHS, and RHS.

Referenced by applyLoopGuards(), IntersectSignedRange(), llvm::splitLoopBound(), and llvm::SCEVRewriteVisitor< SCEVLoopGuardRewriter >::visitSMinExpr().

getSMinExpr() [2/2]

const SCEV * ScalarEvolution::getSMinExpr

(

SmallVectorImpl< const SCEV * > &

Operands

)

Definition at line 4206 of file ScalarEvolution.cpp.

References getMinMaxExpr(), and llvm::scSMinExpr.

getStoreSizeOfExpr()

const SCEV * ScalarEvolution::getStoreSizeOfExpr	(	Type *	IntTy,
		Type *	StoreTy
	)

Return an expression for the store size of StoreTy that is type IntTy.

Definition at line 4243 of file ScalarEvolution.cpp.

References getConstant(), getDataLayout(), and getSizeOfScalableVectorExpr().

Referenced by llvm::RuntimePointerChecking::insert().

getStrengthenedNoWrapFlagsFromBinOp()

std::pair< SCEV::NoWrapFlags, bool > ScalarEvolution::getStrengthenedNoWrapFlagsFromBinOp

(

const OverflowingBinaryOperator *

OBO

)

Parse NSW/NUW flags from add/sub/mul IR binary operation Op into SCEV no-wrap flags, and deduce flag[s] that aren't known yet.

Does not mutate the original instruction.

Definition at line 2323 of file ScalarEvolution.cpp.

References llvm::MCID::Add, llvm::SCEV::FlagNSW, llvm::SCEV::FlagNUW, llvm::Operator::getOpcode(), llvm::User::getOperand(), getSCEV(), llvm::OverflowingBinaryOperator::hasNoSignedWrap(), llvm::OverflowingBinaryOperator::hasNoUnsignedWrap(), LHS, Mul, RHS, setFlags(), and willNotOverflow().

getSymbolicMaxBackedgeTakenCount()

const SCEV* llvm::ScalarEvolution::getSymbolicMaxBackedgeTakenCount ( const Loop *  L )

inline

When successful, this returns a SCEV that is greater than or equal to (i.e.

a "conservative over-approximation") of the value returend by getBackedgeTakenCount. If such a value cannot be computed, it returns the SCEVCouldNotCompute object.

Definition at line 895 of file ScalarEvolution.h.

References getBackedgeTakenCount(), and SymbolicMaximum.

getTripCountFromExitCount()

const SCEV * ScalarEvolution::getTripCountFromExitCount	(	const SCEV *	ExitCount,
		bool	Extend = true
	)

Convert from an "exit count" (i.e.

"backedge taken count") to a "trip count". A "trip count" is the number of times the header of the loop will execute if an exit is taken after the specified number of backedges have been taken. (e.g. TripCount = ExitCount + 1). Note that the expression can overflow if ExitCount = UINT_MAX. Extend controls how potential overflow is handled. If true, a wider result type is returned. ex: EC = 255 (i8), TC = 256 (i9). If false, result unsigned wraps with 2s-complement semantics. ex: EC = 255 (i8), TC = 0 (i8)

Definition at line 7644 of file ScalarEvolution.cpp.

References assert(), getAddExpr(), getCouldNotCompute(), llvm::Type::getIntNTy(), getNoopOrZeroExtend(), getOne(), and llvm::SCEV::getType().

Referenced by computeTripCount(), getSmallConstantTripMultiple(), and verifyTripCount().

getTruncateExpr()

const SCEV * ScalarEvolution::getTruncateExpr	(	const SCEV *	Op,
		Type *	Ty,
		unsigned	Depth = 0
	)

Definition at line 1203 of file ScalarEvolution.cpp.

References assert(), llvm::Depth, llvm::numbers::e, llvm::SCEV::FlagAnyWrap, getAddExpr(), getAddRecExpr(), getConstant(), getEffectiveSCEVType(), GetMinTrailingZeros(), getMulExpr(), llvm::ConstantExpr::getTrunc(), getTruncateOrSignExtend(), getTruncateOrZeroExtend(), getTypeSizeInBits(), getZero(), i, isSCEVable(), llvm_unreachable, MaxCastDepth, Operands, registerUser(), S, llvm::PPCISD::SC, llvm::scTruncate, llvm::X86AS::SS, and llvm::ARM_MB::ST.

Referenced by generateLoopLatchCheck(), genLoopLimit(), getAddExpr(), getCastExpr(), getTruncateOrNoop(), getTruncateOrSignExtend(), getTruncateOrZeroExtend(), getURemExpr(), getZeroExtendExpr(), optimizeLoopExitWithUnknownExitCount(), and llvm::SCEVRewriteVisitor< SCEVLoopGuardRewriter >::visitTruncateExpr().

getTruncateOrNoop()

const SCEV * ScalarEvolution::getTruncateOrNoop	(	const SCEV *	V,
		Type *	Ty
	)

Return a SCEV corresponding to a conversion of the input value to the specified type.

The conversion must not be widening.

Definition at line 4634 of file ScalarEvolution.cpp.

References assert(), getTruncateExpr(), llvm::SCEV::getType(), getTypeSizeInBits(), and llvm::Type::isIntOrPtrTy().

Referenced by canBeCheaplyTransformed(), getAnyExtendExpr(), and llvm::InnerLoopVectorizer::getOrCreateTripCount().

getTruncateOrSignExtend()

const SCEV * ScalarEvolution::getTruncateOrSignExtend	(	const SCEV *	V,
		Type *	Ty,
		unsigned	Depth = 0
	)

Return a SCEV corresponding to a conversion of the input value to the specified type.

If the type must be extended, it is sign extended.

Definition at line 4585 of file ScalarEvolution.cpp.

References assert(), llvm::Depth, getSignExtendExpr(), getTruncateExpr(), llvm::SCEV::getType(), getTypeSizeInBits(), and llvm::Type::isIntOrPtrTy().

Referenced by getGEPExpr(), getSignExtendExpr(), and getTruncateExpr().

getTruncateOrZeroExtend()

const SCEV * ScalarEvolution::getTruncateOrZeroExtend	(	const SCEV *	V,
		Type *	Ty,
		unsigned	Depth = 0
	)

Return a SCEV corresponding to a conversion of the input value to the specified type.

If the type must be extended, it is zero extended.

Definition at line 4573 of file ScalarEvolution.cpp.

References assert(), llvm::Depth, getTruncateExpr(), llvm::SCEV::getType(), getTypeSizeInBits(), getZeroExtendExpr(), and llvm::Type::isIntOrPtrTy().

Referenced by BinomialCoefficient(), llvm::AlignmentFromAssumptionsPass::extractAlignmentInfo(), genLoopLimit(), getNewAlignment(), getNumBytes(), getPtrToIntExpr(), getSignExtendExpr(), getStartForNegStride(), getTripCount(), getTruncateExpr(), and getZeroExtendExpr().

getTypeSizeInBits()

uint64_t ScalarEvolution::getTypeSizeInBits

(

Type *

Ty

)

const

Return the size in bits of the specified type, for which isSCEVable must return true.

Definition at line 4299 of file ScalarEvolution.cpp.

References assert(), getDataLayout(), llvm::DataLayout::getIndexTypeSizeInBits(), llvm::DataLayout::getTypeSizeInBits(), llvm::Type::isPointerTy(), and isSCEVable().

Referenced by llvm::IVUsers::AddUsersIfInteresting(), llvm::SCEVAAResult::alias(), BinomialCoefficient(), computeConstantDifference(), FindLoopCounter(), genLoopLimit(), getAddExpr(), getAnyExtendExpr(), getLosslessPtrToIntExpr(), getMulExpr(), getNoopOrAnyExtend(), getNoopOrSignExtend(), getNoopOrZeroExtend(), llvm::SCEVAddRecExpr::getNumIterationsInRange(), llvm::InnerLoopVectorizer::getOrCreateTripCount(), getPreStartForExtend(), getSignedOverflowLimitForStep(), getSignExtendExpr(), getTruncateExpr(), getTruncateOrNoop(), getTruncateOrSignExtend(), getTruncateOrZeroExtend(), getUDivExpr(), getUMaxFromMismatchedTypes(), getUnsignedOverflowLimitForStep(), getWiderType(), getZeroExtendExpr(), isAddRecSExtable(), isAddSExtable(), llvm::HardwareLoopInfo::isHardwareLoopCandidate(), isMulSExtable(), isSimpleCastedPHI(), optimizeLoopExitWithUnknownExitCount(), SolveLinEquationWithOverflow(), SolveQuadraticAddRecRange(), verify(), and visitIVCast().

getUDivCeilSCEV()

const SCEV * ScalarEvolution::getUDivCeilSCEV	(	const SCEV *	N,
		const SCEV *	D
	)

Compute ceil(N / D).

N and D are treated as unsigned values.

Since SCEV doesn't have native ceiling division, this generates a SCEV expression of the following form:

umin(N, 1) + floor((N - umin(N, 1)) / D)

A denominator of zero or poison is handled the same way as getUDivExpr().

Definition at line 12134 of file ScalarEvolution.cpp.

References D, getAddExpr(), getMinusSCEV(), getOne(), getUDivExpr(), getUMinExpr(), and N.

Referenced by getConstantMaxTripCountFromArray().

getUDivExactExpr()

const SCEV * ScalarEvolution::getUDivExactExpr	(	const SCEV *	LHS,
		const SCEV *	RHS
	)

Get a canonical unsigned division expression, or something simpler if possible.

There is no representation for an exact udiv in SCEV IR, but we can attempt to remove factors from the LHS and RHS. We can't do this when it's not exact because the udiv may be clearing bits.

Definition at line 3521 of file ScalarEvolution.cpp.

References llvm::drop_begin(), llvm::numbers::e, gcd(), getConstant(), getMulExpr(), llvm::User::getNumOperands(), llvm::User::getOperand(), getUDivExpr(), llvm::Instruction::hasNoUnsignedWrap(), i, llvm::APInt::isIntN(), LHS, Mul, llvm::User::op_begin(), llvm::User::op_end(), Operands, llvm::User::operands(), and RHS.

Referenced by SolveLinEquationWithOverflow().

getUDivExpr()

const SCEV * ScalarEvolution::getUDivExpr	(	const SCEV *	LHS,
		const SCEV *	RHS
	)

Get a canonical unsigned division expression, or something simpler if possible.

Get a canonical UDivExpr for a recurrence. {X,+,N}/C => {Y,+,N}/C where Y=X-(XN). Safe when CN=0.

Definition at line 3345 of file ScalarEvolution.cpp.

References assert(), llvm::numbers::e, llvm::SCEV::FlagAnyWrap, llvm::SCEV::FlagNW, llvm::IntegerType::get(), getAddExpr(), getAddRecExpr(), llvm::SCEVConstant::getAPInt(), getConstant(), getContext(), getMulExpr(), llvm::Value::getType(), getTypeSizeInBits(), llvm::ConstantExpr::getUDiv(), getZeroExtendExpr(), i, llvm::Type::isPointerTy(), LHS, M, Operands, registerUser(), RHS, S, llvm::scUDivExpr, llvm::APInt::umul_ov(), and llvm::APInt::urem().

Referenced by applyLoopGuards(), BinomialCoefficient(), llvm::IndexedReference::computeRefCost(), getAddExpr(), getUDivCeilSCEV(), getUDivExactExpr(), getURemExpr(), getZeroExtendExpr(), and llvm::SCEVRewriteVisitor< SCEVLoopGuardRewriter >::visitUDivExpr().

getUMaxExpr() [1/2]

const SCEV * ScalarEvolution::getUMaxExpr	(	const SCEV *	LHS,
		const SCEV *	RHS
	)

Definition at line 4191 of file ScalarEvolution.cpp.

References LHS, and RHS.

Referenced by applyLoopGuards(), getUMaxFromMismatchedTypes(), llvm::RuntimePointerChecking::insert(), IntersectUnsignedRange(), and llvm::SCEVRewriteVisitor< SCEVLoopGuardRewriter >::visitUMaxExpr().

getUMaxExpr() [2/2]

const SCEV * ScalarEvolution::getUMaxExpr

(

SmallVectorImpl< const SCEV * > &

Operands

)

Definition at line 4196 of file ScalarEvolution.cpp.

References getMinMaxExpr(), and llvm::scUMaxExpr.

getUMaxFromMismatchedTypes()

const SCEV * ScalarEvolution::getUMaxFromMismatchedTypes	(	const SCEV *	LHS,
		const SCEV *	RHS
	)

Promote the operands to the wider of the types using zero-extension, and then perform a umax operation with them.

Definition at line 4645 of file ScalarEvolution.cpp.

References getNoopOrZeroExtend(), llvm::Value::getType(), getTypeSizeInBits(), getUMaxExpr(), getZeroExtendExpr(), LHS, and RHS.

getUMinExpr() [1/2]

const SCEV * ScalarEvolution::getUMinExpr	(	const SCEV *	LHS,
		const SCEV *	RHS,
		bool	Sequential = false
	)

Definition at line 4210 of file ScalarEvolution.cpp.

References LHS, and RHS.

Referenced by applyLoopGuards(), createNodeForSelectViaUMinSeq(), getUDivCeilSCEV(), getUMinFromMismatchedTypes(), llvm::RuntimePointerChecking::insert(), IntersectUnsignedRange(), llvm::splitLoopBound(), llvm::SCEVRewriteVisitor< SCEVLoopGuardRewriter >::visitSequentialUMinExpr(), and llvm::SCEVRewriteVisitor< SCEVLoopGuardRewriter >::visitUMinExpr().

getUMinExpr() [2/2]

const SCEV * ScalarEvolution::getUMinExpr	(	SmallVectorImpl< const SCEV * > &	Operands,
		bool	Sequential = false
	)

Definition at line 4216 of file ScalarEvolution.cpp.

References getMinMaxExpr(), getSequentialMinMaxExpr(), llvm::scSequentialUMinExpr, and llvm::scUMinExpr.

getUMinFromMismatchedTypes() [1/2]

const SCEV * ScalarEvolution::getUMinFromMismatchedTypes	(	const SCEV *	LHS,
		const SCEV *	RHS,
		bool	Sequential = false
	)

Promote the operands to the wider of the types using zero-extension, and then perform a umin operation with them.

Definition at line 4658 of file ScalarEvolution.cpp.

References LHS, and RHS.

Referenced by getConstantMaxTripCountFromArray(), and getMinAnalyzeableBackedgeTakenCount().

getUMinFromMismatchedTypes() [2/2]

const SCEV * ScalarEvolution::getUMinFromMismatchedTypes	(	SmallVectorImpl< const SCEV * > &	Ops,
		bool	Sequential = false
	)

Promote the operands to the wider of the types using zero-extension, and then perform a umin operation with them.

N-ary function.

Definition at line 4666 of file ScalarEvolution.cpp.

References assert(), getNoopOrZeroExtend(), getUMinExpr(), getWiderType(), and S.

getUnknown()

const SCEV * ScalarEvolution::getUnknown

(

Value *

V

)

Definition at line 4262 of file ScalarEvolution.cpp.

References assert(), S, SCEVUnknown, and llvm::scUnknown.

Referenced by getSizeOfScalableVectorExpr(), llvm::InductionDescriptor::isFPInductionPHI(), and verify().

getUnsignedRange()

ConstantRange llvm::ScalarEvolution::getUnsignedRange ( const SCEV *  S )

inline

Determine the unsigned range for a particular SCEV.

NOTE: This returns a copy of the reference returned by getRangeRef.

Definition at line 946 of file ScalarEvolution.h.

References S.

Referenced by llvm::SCEVAAResult::alias(), getBoundsCheckCond(), getZeroExtendExpr(), mustBeFiniteCountedLoop(), print(), and StrengthenNoWrapFlags().

getUnsignedRangeMax()

APInt llvm::ScalarEvolution::getUnsignedRangeMax ( const SCEV *  S )

inline

Determine the max of the unsigned range for a particular SCEV.

Definition at line 956 of file ScalarEvolution.h.

References llvm::ConstantRange::getUnsignedMax(), and S.

Referenced by getUnsignedOverflowLimitForStep(), llvm::ARMTTIImpl::isHardwareLoopProfitable(), and SimplifyICmpOperands().

getUnsignedRangeMin()

APInt llvm::ScalarEvolution::getUnsignedRangeMin ( const SCEV *  S )

inline

Determine the min of the unsigned range for a particular SCEV.

Definition at line 951 of file ScalarEvolution.h.

References llvm::ConstantRange::getUnsignedMin(), and S.

Referenced by isKnownNonZero(), and SimplifyICmpOperands().

getURemExpr()

const SCEV * ScalarEvolution::getURemExpr	(	const SCEV *	LHS,
		const SCEV *	RHS
	)

Represents an unsigned remainder expression based on unsigned division.

Definition at line 3316 of file ScalarEvolution.cpp.

References assert(), llvm::SCEV::FlagNUW, llvm::IntegerType::get(), getContext(), getEffectiveSCEVType(), getMinusSCEV(), getMulExpr(), getTruncateExpr(), llvm::Value::getType(), getUDivExpr(), getZero(), getZeroExtendExpr(), LHS, llvm::MipsISD::Mult, and RHS.

Referenced by llvm::LoopVectorizationCostModel::computeMaxVF(), getNewAlignmentDiff(), and getZeroExtendExpr().

getWiderType()

Type * ScalarEvolution::getWiderType	(	Type *	Ty1,
		Type *	Ty2
	)		const

Definition at line 4320 of file ScalarEvolution.cpp.

References getTypeSizeInBits(), and T1.

Referenced by llvm::IndexedReference::computeRefCost(), and getUMinFromMismatchedTypes().

getWrapPredicate()

const SCEVPredicate * ScalarEvolution::getWrapPredicate	(	const SCEVAddRecExpr *	AR,
		SCEVWrapPredicate::IncrementWrapFlags	AddedFlags
	)

Definition at line 13820 of file ScalarEvolution.cpp.

References llvm::SCEVPredicate::P_Wrap, and S.

Referenced by llvm::PredicatedScalarEvolution::setNoOverflow().

getZero()

const SCEV* llvm::ScalarEvolution::getZero ( Type *  Ty )

inline

Return a SCEV for the constant 0 of a specific type.

Definition at line 642 of file ScalarEvolution.h.

References getConstant().

Referenced by detectShiftUntilZeroIdiom(), llvm::AlignmentFromAssumptionsPass::extractAlignmentInfo(), getAddExpr(), getLosslessPtrToIntExpr(), getMinusSCEV(), getMulExpr(), llvm::SCEVAddRecExpr::getNumIterationsInRange(), getSequentialMinMaxExpr(), getTruncateExpr(), getURemExpr(), llvm::isKnownNegativeInLoop(), llvm::isKnownNonNegativeInLoop(), isLoopBackedgeGuardedByCond(), and removePointerBase().

getZeroExtendExpr()

const SCEV * ScalarEvolution::getZeroExtendExpr	(	const SCEV *	Op,
		Type *	Ty,
		unsigned	Depth = 0
	)

Definition at line 1594 of file ScalarEvolution.cpp.

References assert(), llvm::AssumptionCache::assumptions(), llvm::BitWidth, llvm::ConstantRange::contains(), D, llvm::Depth, extractConstantWithoutWrapping(), llvm::SCEV::FlagAnyWrap, llvm::SCEV::FlagNSW, llvm::SCEV::FlagNUW, llvm::SCEV::FlagNW, llvm::IntegerType::get(), getAddExpr(), getAddRecExpr(), getConstant(), getConstantMaxBackedgeTakenCount(), getContext(), getEffectiveSCEVType(), llvm::APInt::getMaxValue(), getMulExpr(), getSignedRangeMin(), getSignExtendExpr(), getTruncateExpr(), getTruncateOrZeroExtend(), llvm::SCEV::getType(), getTypeSizeInBits(), getUDivExpr(), getUnsignedRange(), getURemExpr(), llvm::ConstantExpr::getZExt(), llvm::CmpInst::ICMP_UGT, isKnownNegative(), isKnownOnEveryIteration(), isLoopBackedgeGuardedByCond(), isSCEVable(), LHS, MaxCastDepth, N, registerUser(), RHS, S, llvm::PPCISD::SC, llvm::scZeroExtend, setNoWrapFlags(), llvm::ARM_MB::ST, llvm::ConstantRange::truncate(), X, llvm::ConstantRange::zeroExtend(), and llvm::ConstantRange::zextOrTrunc().

Referenced by genLoopLimit(), getAnyExtendExpr(), getCastExpr(), getNoopOrZeroExtend(), getSignExtendExpr(), getTripCount(), getTruncateOrZeroExtend(), getUDivExpr(), getUMaxFromMismatchedTypes(), getURemExpr(), IsIncrementNUW(), isSafeDependenceDistance(), optimizeLoopExitWithUnknownExitCount(), verify(), verifyTripCount(), llvm::SCEVRewriteVisitor< SCEVLoopGuardRewriter >::visitZeroExtendExpr(), and willNotOverflow().

hasComputableLoopEvolution()

bool ScalarEvolution::hasComputableLoopEvolution	(	const SCEV *	S,
		const Loop *	L
	)

Return true if the given SCEV changes value in a known way in the specified loop.

This property being true implies that the value is variant in the loop AND that we can emit an expression to compute the value of the expression at any particular loop iteration.

Definition at line 13243 of file ScalarEvolution.cpp.

References getLoopDisposition(), LoopComputable, and S.

hasFlags()

static LLVM_NODISCARD bool llvm::ScalarEvolution::hasFlags ( SCEV::NoWrapFlags  Flags, SCEV::NoWrapFlags  TestFlags  )

inlinestatic

Definition at line 481 of file ScalarEvolution.h.

References maskFlags().

Referenced by getAddExpr(), getMinusSCEV(), and StrengthenNoWrapFlags().

hasLoopInvariantBackedgeTakenCount()

bool ScalarEvolution::hasLoopInvariantBackedgeTakenCount

(

const Loop *

L

)

Return true if the specified loop has an analyzable loop-invariant backedge-taken count.

Definition at line 12969 of file ScalarEvolution.cpp.

References getBackedgeTakenCount().

Referenced by llvm::ARMTTIImpl::isHardwareLoopProfitable(), llvm::IVUsers::print(), and PrintLoopInfo().

hasOperand()

bool ScalarEvolution::hasOperand	(	const SCEV *	S,
		const SCEV *	Op
	)		const

Test whether the given SCEV has Op as a direct or indirect operand.

Definition at line 13342 of file ScalarEvolution.cpp.

References S, and llvm::SCEVExprContains().

instructionCouldExistWitthOperands()

bool ScalarEvolution::instructionCouldExistWitthOperands	(	const SCEV *	A,
		const SCEV *	B
	)

Return true if there exists a point in the program at which both A and B could be operands to the same instruction.

SCEV expressions are generally assumed to correspond to instructions which could exists in IR. In general, this requires that there exists a use point in the program where all operands dominate the use.

Example: loop { if loop { v1 = load @global1; } else loop { v2 = load @global2; } } No SCEV with operand V1, and v2 can exist in this program.

For a valid use point to exist, the defining scope of one operand must dominate the other.

Definition at line 4324 of file ScalarEvolution.cpp.

References B, and llvm::DominatorTree::dominates().

Referenced by canComputePointerDiff().

invalidate()

bool ScalarEvolution::invalidate	(	Function &	F,
		const PreservedAnalyses &	PA,
		FunctionAnalysisManager::Invalidator &	Inv
	)

Definition at line 13711 of file ScalarEvolution.cpp.

References F, llvm::PreservedAnalyses::getChecker(), and llvm::AnalysisManager< IRUnitT, ExtraArgTs >::Invalidator::invalidate().

isAvailableAtLoopEntry()

bool ScalarEvolution::isAvailableAtLoopEntry	(	const SCEV *	S,
		const Loop *	L
	)

Determine if the SCEV can be evaluated at loop's entry.

It is true if it doesn't depend on a SCEVUnknown of an instruction which is dominated by the header of loop L.

Definition at line 2448 of file ScalarEvolution.cpp.

References llvm::LoopBase< BlockT, LoopT >::getHeader(), isLoopInvariant(), properlyDominates(), and S.

Referenced by llvm::cannotBeMaxInLoop(), llvm::cannotBeMinInLoop(), getAddExpr(), getMulExpr(), llvm::hasProcessableCondition(), llvm::isKnownNegativeInLoop(), llvm::isKnownNonNegativeInLoop(), isKnownViaInduction(), isLoopEntryGuardedByCond(), isSafeDecreasingBound(), and isSafeIncreasingBound().

isBackedgeTakenCountMaxOrZero()

bool ScalarEvolution::isBackedgeTakenCountMaxOrZero

(

const Loop *

L

)

Return true if the backedge taken count is either the value returned by getConstantMaxBackedgeTakenCount or zero.

Definition at line 7913 of file ScalarEvolution.cpp.

Referenced by PrintLoopInfo(), tryToUnrollLoop(), and llvm::UnrollLoop().

isBasicBlockEntryGuardedByCond()

bool ScalarEvolution::isBasicBlockEntryGuardedByCond	(	const BasicBlock *	BB,
		ICmpInst::Predicate	Pred,
		const SCEV *	LHS,
		const SCEV *	RHS
	)

Test whether entry to the basic block is protected by a conditional between LHS and RHS.

Definition at line 10924 of file ScalarEvolution.cpp.

References assert(), llvm::AssumptionCache::assumptions(), BB, llvm::dbgs(), llvm::DominatorTree::dominates(), function, llvm::BranchInst::getCondition(), llvm::LoopBase< BlockT, LoopT >::getHeader(), llvm::LoopInfoBase< BlockT, LoopT >::getLoopFor(), llvm::LoopBase< BlockT, LoopT >::getLoopPredecessor(), llvm::CmpInst::getNonStrictPredicate(), llvm::BranchInst::getSuccessor(), llvm::CmpInst::ICMP_NE, llvm::BranchInst::isUnconditional(), LHS, P, RHS, llvm::verifyFunction(), and VerifyIR.

Referenced by evaluatePredicateAt(), isKnownPredicateAt(), and isLoopEntryGuardedByCond().

isKnownNegative()

bool ScalarEvolution::isKnownNegative

(

const SCEV *

S

)

Test if the given expression is known to be negative.

Definition at line 10320 of file ScalarEvolution.cpp.

References getSignedRangeMax(), llvm::APInt::isNegative(), and S.

Referenced by llvm::IndexedReference::computeRefCost(), getSignedOverflowLimitForStep(), getZeroExtendExpr(), isOneDimensionalArray(), and isSafeDecreasingBound().

isKnownNonNegative()

bool ScalarEvolution::isKnownNonNegative

(

const SCEV *

S

)

Test if the given expression is known to be non-negative.

Definition at line 10328 of file ScalarEvolution.cpp.

References getSignedRangeMin(), llvm::APInt::isNegative(), and S.

Referenced by detectShiftUntilZeroIdiom(), getGEPExpr(), getMinusSCEV(), getSignExtendExpr(), and StrengthenNoWrapFlags().

isKnownNonPositive()

bool ScalarEvolution::isKnownNonPositive

(

const SCEV *

S

)

Test if the given expression is known to be non-positive.

Definition at line 10332 of file ScalarEvolution.cpp.

References getSignedRangeMax(), llvm::APInt::isStrictlyPositive(), and S.

isKnownNonZero()

bool ScalarEvolution::isKnownNonZero

(

const SCEV *

S

)

Test if the given expression is known to be non-zero.

Definition at line 10336 of file ScalarEvolution.cpp.

References getUnsignedRangeMin(), and S.

Referenced by breakBackedgeIfNotTaken().

isKnownOnEveryIteration()

bool ScalarEvolution::isKnownOnEveryIteration	(	ICmpInst::Predicate	Pred,
		const SCEVAddRecExpr *	LHS,
		const SCEV *	RHS
	)

Test if the condition described by Pred, LHS, RHS is known to be true on every iteration of the loop of the recurrency LHS.

Definition at line 10453 of file ScalarEvolution.cpp.

References isLoopBackedgeGuardedByCond(), isLoopEntryGuardedByCond(), LHS, and RHS.

Referenced by getZeroExtendExpr().

isKnownPositive()

bool ScalarEvolution::isKnownPositive

(

const SCEV *

S

)

Test if the given expression is known to be positive.

Definition at line 10324 of file ScalarEvolution.cpp.

References getSignedRangeMin(), llvm::APInt::isStrictlyPositive(), and S.

Referenced by getPreStartForExtend(), getSignedOverflowLimitForStep(), and isSafeDependenceDistance().

isKnownPredicate()

bool ScalarEvolution::isKnownPredicate	(	ICmpInst::Predicate	Pred,
		const SCEV *	LHS,
		const SCEV *	RHS
	)

Test if the given expression is known to satisfy the condition described by Pred, LHS, and RHS.

Definition at line 10403 of file ScalarEvolution.cpp.

References isKnownViaInduction(), LHS, RHS, and SimplifyICmpOperands().

Referenced by llvm::calculateUpperBound(), countToEliminateCompares(), evaluatePredicate(), isKnownPredicateAt(), IsKnownPredicateViaAddRecStart(), and normalizePredicate().

isKnownPredicateAt()

bool ScalarEvolution::isKnownPredicateAt	(	ICmpInst::Predicate	Pred,
		const SCEV *	LHS,
		const SCEV *	RHS,
		const Instruction *	CtxI
	)

Test if the given expression is known to satisfy the condition described by Pred, LHS, and RHS in the given Context.

Definition at line 10428 of file ScalarEvolution.cpp.

References llvm::Instruction::getParent(), isBasicBlockEntryGuardedByCond(), isKnownPredicate(), LHS, and RHS.

Referenced by canOverlap(), getLoopInvariantExitCondDuringFirstIterations(), and optimizeLoopExitWithUnknownExitCount().

isKnownViaInduction()

bool ScalarEvolution::isKnownViaInduction	(	ICmpInst::Predicate	Pred,
		const SCEV *	LHS,
		const SCEV *	RHS
	)

We'd like to check the predicate on every iteration of the most dominated loop between loops used in LHS and RHS.

To do this we use the following list of steps:

1. Collect set S all loops on which either LHS or RHS depend.
2. If S is non-empty a. Let PD be the element of S which is dominated by all other elements. b. Let E(LHS) be value of LHS on entry of PD. To get E(LHS), we should just take LHS and replace all AddRecs that are attached to PD on with their entry values. Define E(RHS) in the same way. c. Let B(LHS) be value of L on backedge of PD. To get B(LHS), we should just take LHS and replace all AddRecs that are attached to PD on with their backedge values. Define B(RHS) in the same way. d. Note that E(LHS) and E(RHS) are automatically available on entry of PD, so we can assert on that. e. Return true if isLoopEntryGuardedByCond(Pred, E(LHS), E(RHS)) && isLoopBackedgeGuardedByCond(Pred, B(LHS), B(RHS))

Definition at line 10352 of file ScalarEvolution.cpp.

References assert(), llvm::DominatorTree::dominates(), llvm::SmallPtrSetImplBase::empty(), getCouldNotCompute(), isAvailableAtLoopEntry(), isLoopBackedgeGuardedByCond(), isLoopEntryGuardedByCond(), L2, LHS, RHS, and SplitIntoInitAndPostInc().

Referenced by isKnownPredicate().

isLoopBackedgeGuardedByCond()

bool ScalarEvolution::isLoopBackedgeGuardedByCond	(	const Loop *	L,
		ICmpInst::Predicate	Pred,
		const SCEV *	LHS,
		const SCEV *	RHS
	)

Test whether the backedge of the loop is protected by a conditional between LHS and RHS.

isLoopBackedgeGuardedByCond - Test whether the backedge of the loop is protected by a conditional between LHS and RHS.

This is used to eliminate casts.

This is used to to eliminate casts.

Definition at line 10815 of file ScalarEvolution.cpp.

References assert(), llvm::AssumptionCache::assumptions(), BB, llvm::dbgs(), llvm::DominatorTree::dominates(), llvm::SCEV::FlagNUW, llvm::SCEV::FlagNW, getAddRecExpr(), llvm::BranchInst::getCondition(), getCouldNotCompute(), llvm::LoopBase< BlockT, LoopT >::getHeader(), llvm::LoopBase< BlockT, LoopT >::getLoopLatch(), getOne(), llvm::BasicBlock::getParent(), llvm::BranchInst::getSuccessor(), llvm::BasicBlock::getTerminator(), llvm::SCEV::getType(), getZero(), llvm::CmpInst::ICMP_ULT, llvm::BranchInst::isConditional(), llvm::DominatorTree::isReachableFromEntry(), llvm::BasicBlockEdge::isSingleEdge(), LHS, RHS, llvm::verifyFunction(), and VerifyIR.

Referenced by getLoopInvariantExitCondDuringFirstIterations(), getLoopInvariantPredicate(), getZeroExtendExpr(), isKnownOnEveryIteration(), and isKnownViaInduction().

isLoopEntryGuardedByCond()

bool ScalarEvolution::isLoopEntryGuardedByCond	(	const Loop *	L,
		ICmpInst::Predicate	Pred,
		const SCEV *	LHS,
		const SCEV *	RHS
	)

Test whether entry to the loop is protected by a conditional between LHS and RHS.

This is used to help avoid max expressions in loop trip counts, and to eliminate casts.

Definition at line 11030 of file ScalarEvolution.cpp.

References assert(), llvm::LoopBase< BlockT, LoopT >::getHeader(), isAvailableAtLoopEntry(), isBasicBlockEntryGuardedByCond(), LHS, and RHS.

Referenced by llvm::cannotBeMaxInLoop(), llvm::cannotBeMinInLoop(), llvm::findSplitCandidate(), getPreStartForExtend(), getTripCount(), llvm::isKnownNegativeInLoop(), llvm::isKnownNonNegativeInLoop(), isKnownOnEveryIteration(), isKnownViaInduction(), isSafeDecreasingBound(), and isSafeIncreasingBound().

isLoopInvariant()

bool ScalarEvolution::isLoopInvariant	(	const SCEV *	S,
		const Loop *	L
	)

Return true if the value of the given SCEV is unchanging in the specified loop.

Definition at line 13239 of file ScalarEvolution.cpp.

References getLoopDisposition(), LoopInvariant, and S.

Referenced by llvm::RecurrenceDescriptor::AddReductionVar(), canTailPredicateLoop(), computeUnrollAndJamCount(), CreateStepValue(), createWidenInductionRecipes(), genLoopLimit(), getAddRecExpr(), getConstantMaxTripCountFromArray(), getLoopInvariantExitCondDuringFirstIterations(), getLoopInvariantPredicate(), hasComputableBounds(), llvm::RuntimePointerChecking::insert(), llvm::Loop::isAuxiliaryInductionVariable(), isAvailableAtLoopEntry(), llvm::isDereferenceableAndAlignedInLoop(), llvm::HardwareLoopInfo::isHardwareLoopCandidate(), llvm::InductionDescriptor::isInductionPHI(), isNoWrap(), isOneDimensionalArray(), llvm::LoopAccessInfo::isUniform(), mayUsePostIncMode(), print(), llvm::rewriteLoopExitValues(), SimplifyICmpOperands(), llvm::stripGetElementPtr(), llvm::VPRecipeBuilder::tryToCreateWidenRecipe(), and llvm::VPlanTransforms::VPInstructionsToVPRecipes().

isSCEVable()

bool ScalarEvolution::isSCEVable

(

Type *

Ty

)

const

Test if values of the given type are analyzable within the SCEV framework.

This primarily includes integer types, and it can optionally include pointer types if the ScalarEvolution class has access to target-specific information.

Definition at line 4292 of file ScalarEvolution.cpp.

References llvm::Type::isIntOrPtrTy().

Referenced by llvm::IVUsers::AddUsersIfInteresting(), DbgGatherSalvagableDVI(), findIVOperand(), getAnyExtendExpr(), getEffectiveSCEVType(), GetInductionVariable(), getSCEV(), getSignExtendExpr(), getTruncateExpr(), getTypeSizeInBits(), getZeroExtendExpr(), isExistingPhi(), isHighCostExpansion(), isLoopCounter(), llvm::isProcessableCondBI(), isSimpleIVUser(), llvm::LoopAccessInfo::isUniform(), print(), llvm::PredicatedScalarEvolution::print(), llvm::rewriteLoopExitValues(), and llvm::splitLoopBound().

loopHasNoAbnormalExits()

bool llvm::ScalarEvolution::loopHasNoAbnormalExits ( const Loop *  L )

inline

Return true if the loop has no abnormal exits.

That is, if the loop is not infinite, it must exit through an explicit edge in the CFG. (As opposed to either a) throwing out of the function or b) entering a well defined infinite loop in some callee.)

Definition at line 1199 of file ScalarEvolution.h.

Referenced by llvm::UnrollRuntimeLoopRemainder().

loopIsFiniteByAssumption()

bool ScalarEvolution::loopIsFiniteByAssumption

(

const Loop *

L

)

Return true if this loop is finite by assumption.

That is, to be infinite, it must also be undefined.

Definition at line 7181 of file ScalarEvolution.cpp.

References llvm::isFinite(), and llvm::isMustProgress().

maskFlags()

static LLVM_NODISCARD SCEV::NoWrapFlags llvm::ScalarEvolution::maskFlags ( SCEV::NoWrapFlags  Flags, int  Mask  )

inlinestatic

Convenient NoWrapFlags manipulation that hides enum casts and is visible in the ScalarEvolution name space.

Definition at line 469 of file ScalarEvolution.h.

References llvm::BitmaskEnumDetail::Mask().

Referenced by getAddExpr(), getAddRecExpr(), getMulExpr(), getPreStartForExtend(), hasFlags(), and StrengthenNoWrapFlags().

print()

void ScalarEvolution::print

(

raw_ostream &

OS

)

const

Definition at line 13048 of file ScalarEvolution.cpp.

References ClassifyExpressions, llvm::depth_first(), First, getLoopDisposition(), llvm::LoopInfoBase< BlockT, LoopT >::getLoopFor(), llvm::LoopBase< BlockT, LoopT >::getParentLoop(), getSCEV(), getSCEVAtScope(), getSignedRange(), getUnsignedRange(), I, llvm::instructions(), isLoopInvariant(), isSCEVable(), loopDispositionToStr(), llvm::SCEV::print(), llvm::ConstantRange::print(), llvm::Value::printAsOperand(), and PrintLoopInfo().

Referenced by llvm::ScalarEvolutionWrapperPass::print().

properlyDominates()

bool ScalarEvolution::properlyDominates	(	const SCEV *	S,
		const BasicBlock *	BB
	)

Return true if elements that makes up the given SCEV properly dominate the specified basic block.

Definition at line 13338 of file ScalarEvolution.cpp.

References BB, getBlockDisposition(), ProperlyDominatesBlock, and S.

Referenced by DoInitialMatch(), isAvailableAtLoopEntry(), llvm::isSafeToExpandAt(), and SimplifyICmpOperands().

registerUser()

void ScalarEvolution::registerUser	(	const SCEV *	User,
		ArrayRef< const SCEV * >	Ops
	)

Notify this ScalarEvolution that User directly uses SCEVs in Ops.

Definition at line 14116 of file ScalarEvolution.cpp.

Referenced by getLosslessPtrToIntExpr(), getMinMaxExpr(), getSequentialMinMaxExpr(), getSignExtendExpr(), getTruncateExpr(), getUDivExpr(), and getZeroExtendExpr().

removePointerBase()

const SCEV * ScalarEvolution::removePointerBase

(

const SCEV *

S

)

Compute an expression equivalent to S - getPointerBase(S).

Definition at line 4493 of file ScalarEvolution.cpp.

References assert(), llvm::SCEV::FlagAnyWrap, getAddExpr(), getAddRecExpr(), getZero(), and P.

Referenced by getMinusSCEV().

rewriteUsingPredicate()

const SCEV * ScalarEvolution::rewriteUsingPredicate	(	const SCEV *	S,
		const Loop *	L,
		const SCEVPredicate &	A
	)

Re-writes the SCEV according to the Predicates in A.

Definition at line 13960 of file ScalarEvolution.cpp.

References rewrite(), and S.

setFlags()

static LLVM_NODISCARD SCEV::NoWrapFlags llvm::ScalarEvolution::setFlags ( SCEV::NoWrapFlags  Flags, SCEV::NoWrapFlags  OnFlags  )

inlinestatic

Definition at line 473 of file ScalarEvolution.h.

Referenced by getAddExpr(), llvm::SCEVWrapPredicate::getImpliedFlags(), getStrengthenedNoWrapFlagsFromBinOp(), llvm::SCEVWrapPredicate::isAlwaysTrue(), llvm::SCEVAddRecExpr::setNoWrapFlags(), and StrengthenNoWrapFlags().

setNoWrapFlags()

void ScalarEvolution::setNoWrapFlags	(	SCEVAddRecExpr *	AddRec,
		SCEV::NoWrapFlags	Flags
	)

Update no-wrap flags of an AddRec.

This may drop the cached info about this AddRec (such as range info) in case if new flags may potentially sharpen it.

Definition at line 6271 of file ScalarEvolution.cpp.

References llvm::SCEVNAryExpr::getNoWrapFlags(), and llvm::SCEVAddRecExpr::setNoWrapFlags().

Referenced by getPreStartForExtend(), getSignExtendExpr(), and getZeroExtendExpr().

SimplifyICmpOperands()

bool ScalarEvolution::SimplifyICmpOperands	(	ICmpInst::Predicate &	Pred,
		const SCEV *&	LHS,
		const SCEV *&	RHS,
		unsigned	Depth = 0,
		bool	ControllingFiniteLoop = false
	)

Simplify LHS and RHS in a comparison with predicate Pred.

Return true iff any changes were made. If the operands are provably equal or unequal, LHS and RHS are set to the same value and Pred is set to either ICMP_EQ or ICMP_NE. ControllingFiniteLoop is set if this comparison controls the exit of a loop known to have a finite number of iterations.

Definition at line 10116 of file ScalarEvolution.cpp.

References assert(), llvm::Depth, llvm::SCEV::FlagNSW, llvm::SCEV::FlagNUW, getAddExpr(), getConstant(), getContext(), llvm::ConstantRange::getEquivalentICmp(), llvm::ConstantInt::getFalse(), llvm::LoopBase< BlockT, LoopT >::getHeader(), llvm::ConstantExpr::getICmp(), llvm::SCEVAddRecExpr::getLoop(), getSignedRangeMax(), getSignedRangeMin(), llvm::CmpInst::getSwappedPredicate(), llvm::Value::getType(), getUnsignedRangeMax(), getUnsignedRangeMin(), HasSameValue(), llvm::CmpInst::ICMP_EQ, llvm::CmpInst::ICMP_NE, llvm::CmpInst::ICMP_SGE, llvm::CmpInst::ICMP_SGT, llvm::CmpInst::ICMP_SLE, llvm::CmpInst::ICMP_SLT, llvm::CmpInst::ICMP_UGE, llvm::CmpInst::ICMP_UGT, llvm::CmpInst::ICMP_ULE, llvm::CmpInst::ICMP_ULT, llvm::ConstantRange::isEmptySet(), llvm::ICmpInst::isEquality(), llvm::CmpInst::isFalseWhenEqual(), llvm::ConstantRange::isFullSet(), isLoopInvariant(), llvm::Constant::isNullValue(), llvm::CmpInst::isTrueWhenEqual(), LHS, llvm::ConstantRange::makeExactICmpRegion(), properlyDominates(), RA, RHS, and std::swap().

Referenced by isKnownPredicate().

SplitIntoInitAndPostInc()

std::pair< const SCEV *, const SCEV * > ScalarEvolution::SplitIntoInitAndPostInc	(	const Loop *	L,
		const SCEV *	S
	)

Splits SCEV expression S into two SCEVs.

One of them is obtained from S by substitution of all AddRec sub-expression related to loop L with initial value of that SCEV. The second is obtained from S by substitution of all AddRec sub-expressions related to loop L with post increment of this AddRec in the loop L. In both cases all other AddRec sub-expressions (not related to L) remain the same. If the S contains non-invariant unknown SCEV the function returns CouldNotCompute SCEV in both values of std::pair. For example, for SCEV S={0, +, 1}<L1> + {0, +, 1}<L2> and loop L=L1 the function returns pair: first = {0, +, 1}<L2> second = {1, +, 1}<L1> + {0, +, 1}<L2> We can see that for the first AddRec sub-expression it was replaced with 0 (initial value) for the first element and to {1, +, 1}<L1> (post increment value) for the second one. In both cases AddRec expression related to L2 remains the same.

Definition at line 10341 of file ScalarEvolution.cpp.

References assert(), getCouldNotCompute(), PostInc, rewrite(), and S.

Referenced by isKnownViaInduction().

verify()

void ScalarEvolution::verify

(

)

const

Definition at line 13490 of file ScalarEvolution.cpp.

References abort(), llvm::SmallVectorImpl< T >::append(), llvm::append_range(), assert(), llvm::LoopBase< BlockT, LoopT >::begin(), llvm::LoopInfoBase< BlockT, LoopT >::begin(), collectUniqueOps(), llvm::SmallPtrSetImpl< PtrType >::contains(), containsUndefs(), llvm::dbgs(), llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::end(), llvm::LoopBase< BlockT, LoopT >::end(), llvm::LoopInfoBase< BlockT, LoopT >::end(), F, llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::find(), getBackedgeTakenCount(), getConstant(), getCouldNotCompute(), llvm::SCEVAddRecExpr::getLoop(), getMinusSCEV(), getSCEV(), getTypeSizeInBits(), getUnknown(), llvm::SCEVUnknown::getValue(), getZeroExtendExpr(), I, llvm::SmallPtrSetImpl< PtrType >::insert(), llvm::is_contained(), llvm::SCEV::isZero(), llvm::SmallVectorImpl< T >::pop_back_val(), S, and VerifySCEVStrict.

Referenced by llvm::FunctionToLoopPassAdaptor::run(), llvm::UnrollAndJamLoop(), and llvm::ScalarEvolutionWrapperPass::verifyAnalysis().

willNotOverflow()

bool ScalarEvolution::willNotOverflow	(	Instruction::BinaryOps	BinOp,
		bool	Signed,
		const SCEV *	LHS,
		const SCEV *	RHS
	)

Is operation BinOp between LHS and RHS provably does not have a signed/unsigned overflow (Signed)?

Definition at line 2287 of file ScalarEvolution.cpp.

References llvm::MCID::Add, B, llvm::SCEV::FlagAnyWrap, llvm::IntegerType::get(), getAddExpr(), getMinusSCEV(), getMulExpr(), getSignExtendExpr(), llvm::Value::getType(), getZeroExtendExpr(), LHS, llvm_unreachable, Mul, Operation, RHS, ScalarEvolution(), and Signed.

Referenced by getStrengthenedNoWrapFlagsFromBinOp().

Friends And Related Function Documentation

ScalarEvolutionsTest

friend class ScalarEvolutionsTest

friend

Definition at line 450 of file ScalarEvolution.h.

SCEVCallbackVH

friend class SCEVCallbackVH

friend

Definition at line 1220 of file ScalarEvolution.h.

Referenced by getSCEV().

SCEVExpander

friend class SCEVExpander

friend

Definition at line 1221 of file ScalarEvolution.h.

SCEVUnknown

friend class SCEVUnknown

friend

Definition at line 1222 of file ScalarEvolution.h.

Referenced by getUnknown().

---

The documentation for this class was generated from the following files:

• include/llvm/Analysis/ScalarEvolution.h
• lib/Analysis/ScalarEvolution.cpp