LLVM  4.0.0
Public Types | Public Member Functions | Static Public Member Functions | List of all members
llvm::InductionDescriptor Class Reference

A struct for saving information about induction variables. More...

#include <LoopUtils.h>

Public Types

enum  InductionKind { IK_NoInduction, IK_IntInduction, IK_PtrInduction, IK_FpInduction }
 This enum represents the kinds of inductions that we support. More...
 

Public Member Functions

 InductionDescriptor ()
 Default constructor - creates an invalid induction. More...
 
int getConsecutiveDirection () const
 Get the consecutive direction. More...
 
Valuetransform (IRBuilder<> &B, Value *Index, ScalarEvolution *SE, const DataLayout &DL) const
 Compute the transformed value of Index at offset StartValue using step StepValue. More...
 
ValuegetStartValue () const
 
InductionKind getKind () const
 
const SCEVgetStep () const
 
ConstantIntgetConstIntStepValue () const
 
bool hasUnsafeAlgebra ()
 Returns true if the induction type is FP and the binary operator does not have the "fast-math" property. More...
 
InstructiongetUnsafeAlgebraInst ()
 Returns induction operator that does not have "fast-math" property and requires FP unsafe mode. More...
 
Instruction::BinaryOps getInductionOpcode () const
 Returns binary opcode of the induction operator. More...
 

Static Public Member Functions

static bool isInductionPHI (PHINode *Phi, const Loop *L, ScalarEvolution *SE, InductionDescriptor &D, const SCEV *Expr=nullptr)
 Returns true if Phi is an induction in the loop L. More...
 
static bool isFPInductionPHI (PHINode *Phi, const Loop *L, ScalarEvolution *SE, InductionDescriptor &D)
 Returns true if Phi is a floating point induction in the loop L. More...
 
static bool isInductionPHI (PHINode *Phi, const Loop *L, PredicatedScalarEvolution &PSE, InductionDescriptor &D, bool Assume=false)
 Returns true if Phi is a loop L induction, in the context associated with the run-time predicate of PSE. More...
 

Detailed Description

A struct for saving information about induction variables.

Definition at line 261 of file LoopUtils.h.

Member Enumeration Documentation

This enum represents the kinds of inductions that we support.

Enumerator
IK_NoInduction 

Not an induction variable.

IK_IntInduction 

Integer induction variable. Step = C.

IK_PtrInduction 

Pointer induction var. Step = C / sizeof(elem).

IK_FpInduction 

Floating point induction variable.

Definition at line 264 of file LoopUtils.h.

Constructor & Destructor Documentation

llvm::InductionDescriptor::InductionDescriptor ( )
inline

Default constructor - creates an invalid induction.

Definition at line 273 of file LoopUtils.h.

Referenced by isFPInductionPHI(), and isInductionPHI().

Member Function Documentation

int InductionDescriptor::getConsecutiveDirection ( ) const

Get the consecutive direction.

Returns: 0 - unknown or non-consecutive. 1 - consecutive and increasing. -1 - consecutive and decreasing.

Definition at line 688 of file LoopUtils.cpp.

References getConstIntStepValue(), llvm::ConstantInt::getSExtValue(), llvm::ConstantInt::isMinusOne(), and llvm::ConstantInt::isOne().

ConstantInt * InductionDescriptor::getConstIntStepValue ( ) const

Definition at line 695 of file LoopUtils.cpp.

References llvm::dyn_cast().

Referenced by getConsecutiveDirection(), and transform().

Instruction::BinaryOps llvm::InductionDescriptor::getInductionOpcode ( ) const
inline

Returns binary opcode of the induction operator.

Definition at line 340 of file LoopUtils.h.

References llvm::BinaryOperator::getOpcode().

InductionKind llvm::InductionDescriptor::getKind ( ) const
inline

Definition at line 293 of file LoopUtils.h.

Value* llvm::InductionDescriptor::getStartValue ( ) const
inline

Definition at line 292 of file LoopUtils.h.

const SCEV* llvm::InductionDescriptor::getStep ( ) const
inline

Definition at line 294 of file LoopUtils.h.

Instruction* llvm::InductionDescriptor::getUnsafeAlgebraInst ( )
inline

Returns induction operator that does not have "fast-math" property and requires FP unsafe mode.

Definition at line 332 of file LoopUtils.h.

References hasUnsafeAlgebra().

bool llvm::InductionDescriptor::hasUnsafeAlgebra ( )
inline

Returns true if the induction type is FP and the binary operator does not have the "fast-math" property.

Such operation requires a relaxed FP mode.

Definition at line 325 of file LoopUtils.h.

Referenced by getUnsafeAlgebraInst().

bool InductionDescriptor::isFPInductionPHI ( PHINode Phi,
const Loop L,
ScalarEvolution SE,
InductionDescriptor D 
)
static
bool InductionDescriptor::isInductionPHI ( PHINode Phi,
const Loop L,
ScalarEvolution SE,
InductionDescriptor D,
const SCEV Expr = nullptr 
)
static
bool InductionDescriptor::isInductionPHI ( PHINode Phi,
const Loop L,
PredicatedScalarEvolution PSE,
InductionDescriptor D,
bool  Assume = false 
)
static

Returns true if Phi is a loop L induction, in the context associated with the run-time predicate of PSE.

If Assume is true, this can add further SCEV predicates to PSE in order to prove that Phi is an induction. If Phi is an induction, D will contain the data describing this induction.

Definition at line 822 of file LoopUtils.cpp.

References D, llvm::dbgs(), DEBUG, llvm::dyn_cast(), llvm::PredicatedScalarEvolution::getAsAddRec(), llvm::PredicatedScalarEvolution::getSCEV(), llvm::PredicatedScalarEvolution::getSE(), llvm::Value::getType(), llvm::Type::isDoubleTy(), llvm::Type::isFloatingPointTy(), llvm::Type::isFloatTy(), isFPInductionPHI(), llvm::Type::isHalfTy(), isInductionPHI(), llvm::Type::isIntegerTy(), and llvm::Type::isPointerTy().

Value * InductionDescriptor::transform ( IRBuilder<> &  B,
Value Index,
ScalarEvolution SE,
const DataLayout DL 
) const

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