#include <TargetTransformInfo.h>

Collaboration diagram for llvm::TargetTransformInfo:

Public Member Functions
virtual	~TargetTransformInfo ()=0
	This class is intended to be subclassed by real implementations.
Static Public Attributes
static char	ID = 0
	Analysis group identification.
Protected Member Functions
void	pushTTIStack (Pass *P)
void	popTTIStack ()
virtual void	getAnalysisUsage (AnalysisUsage &AU) const
	All pass subclasses must call TargetTransformInfo::getAnalysisUsage.
Protected Attributes
TargetTransformInfo *	PrevTTI
	The TTI instance one level down the stack.
TargetTransformInfo *	TopTTI
	The top of the stack of TTI analyses available.
Generic Target Information
enum	TargetCostConstants { TCC_Free = 0, TCC_Basic = 1, TCC_Expensive = 4 }
	Underlying constants for 'cost' values in this interface. More...
virtual unsigned	getOperationCost (unsigned Opcode, Type Ty, Type OpTy=0) const
	Estimate the cost of a specific operation when lowered.
virtual unsigned	getGEPCost (const Value Ptr, ArrayRef< const Value > Operands) const
	Estimate the cost of a GEP operation when lowered.
virtual unsigned	getCallCost (FunctionType *FTy, int NumArgs=-1) const
	Estimate the cost of a function call when lowered.
virtual unsigned	getCallCost (const Function *F, int NumArgs=-1) const
	Estimate the cost of calling a specific function when lowered.
virtual unsigned	getCallCost (const Function F, ArrayRef< const Value > Arguments) const
	Estimate the cost of calling a specific function when lowered.
virtual unsigned	getIntrinsicCost (Intrinsic::ID IID, Type RetTy, ArrayRef< Type > ParamTys) const
	Estimate the cost of an intrinsic when lowered.
virtual unsigned	getIntrinsicCost (Intrinsic::ID IID, Type RetTy, ArrayRef< const Value > Arguments) const
	Estimate the cost of an intrinsic when lowered.
virtual unsigned	getUserCost (const User *U) const
	Estimate the cost of a given IR user when lowered.
virtual bool	isLoweredToCall (const Function *F) const
	Test whether calls to a function lower to actual program function calls.
Scalar Target Information
enum	PopcntSupportKind { PSK_Software, PSK_SlowHardware, PSK_FastHardware }
	Flags indicating the kind of support for population count. More...
virtual bool	isLegalAddImmediate (int64_t Imm) const
virtual bool	isLegalICmpImmediate (int64_t Imm) const
virtual bool	isLegalAddressingMode (Type Ty, GlobalValue BaseGV, int64_t BaseOffset, bool HasBaseReg, int64_t Scale) const
virtual bool	isTruncateFree (Type Ty1, Type Ty2) const
virtual bool	isTypeLegal (Type *Ty) const
	Is this type legal.
virtual unsigned	getJumpBufAlignment () const
	getJumpBufAlignment - returns the target's jmp_buf alignment in bytes
virtual unsigned	getJumpBufSize () const
	getJumpBufSize - returns the target's jmp_buf size in bytes.
virtual bool	shouldBuildLookupTables () const
virtual PopcntSupportKind	getPopcntSupport (unsigned IntTyWidthInBit) const
	getPopcntSupport - Return hardware support for population count.
virtual unsigned	getIntImmCost (const APInt &Imm, Type *Ty) const
Vector Target Information
enum	ShuffleKind { SK_Broadcast, SK_Reverse, SK_InsertSubvector, SK_ExtractSubvector }
	The various kinds of shuffle patterns for vector queries. More...
enum	OperandValueKind { OK_AnyValue, OK_UniformValue, OK_UniformConstantValue }
	Additonal information about an operand's possible values. More...
virtual unsigned	getNumberOfRegisters (bool Vector) const
virtual unsigned	getRegisterBitWidth (bool Vector) const
virtual unsigned	getMaximumUnrollFactor () const
virtual unsigned	getArithmeticInstrCost (unsigned Opcode, Type *Ty, OperandValueKind Opd1Info=OK_AnyValue, OperandValueKind Opd2Info=OK_AnyValue) const
virtual unsigned	getShuffleCost (ShuffleKind Kind, Type Tp, int Index=0, Type SubTp=0) const
virtual unsigned	getCastInstrCost (unsigned Opcode, Type Dst, Type Src) const
virtual unsigned	getCFInstrCost (unsigned Opcode) const
virtual unsigned	getCmpSelInstrCost (unsigned Opcode, Type ValTy, Type CondTy=0) const
virtual unsigned	getVectorInstrCost (unsigned Opcode, Type *Val, unsigned Index=-1) const
virtual unsigned	getMemoryOpCost (unsigned Opcode, Type *Src, unsigned Alignment, unsigned AddressSpace) const
virtual unsigned	getIntrinsicInstrCost (Intrinsic::ID ID, Type RetTy, ArrayRef< Type > Tys) const
virtual unsigned	getNumberOfParts (Type *Tp) const
virtual unsigned	getAddressComputationCost (Type *Ty) const

Detailed Description

TargetTransformInfo - This pass provides access to the codegen interfaces that are needed for IR-level transformations.

Definition at line 38 of file TargetTransformInfo.h.

Member Enumeration Documentation

enum llvm::TargetTransformInfo::OperandValueKind

Additonal information about an operand's possible values.

Enumerator:

OK_AnyValue
OK_UniformValue
OK_UniformConstantValue

Definition at line 267 of file TargetTransformInfo.h.

enum llvm::TargetTransformInfo::PopcntSupportKind

Flags indicating the kind of support for population count.

Compared to the SW implementation, HW support is supposed to significantly boost the performance when the population is dense, and it may or may not degrade performance if the population is sparse. A HW support is considered as "Fast" if it can outperform, or is on a par with, SW implementation when the population is sparse; otherwise, it is considered as "Slow".

Enumerator:

PSK_Software
PSK_SlowHardware
PSK_FastHardware

Definition at line 201 of file TargetTransformInfo.h.

enum llvm::TargetTransformInfo::ShuffleKind

The various kinds of shuffle patterns for vector queries.

Enumerator:

SK_Broadcast	Broadcast element 0 to all other elements.
SK_Reverse	Reverse the order of the vector.
SK_InsertSubvector	InsertSubvector. Index indicates start offset.
SK_ExtractSubvector	ExtractSubvector Index indicates start offset.

Definition at line 259 of file TargetTransformInfo.h.

enum llvm::TargetTransformInfo::TargetCostConstants

Underlying constants for 'cost' values in this interface.

Many APIs in this interface return a cost. This enum defines the fundamental values that should be used to interpret (and produce) those costs. The costs are returned as an unsigned rather than a member of this enumeration because it is expected that the cost of one IR instruction may have a multiplicative factor to it or otherwise won't fit directly into the enum. Moreover, it is common to sum or average costs which works better as simple integral values. Thus this enum only provides constants.

Note that these costs should usually reflect the intersection of code-size cost and execution cost. A free instruction is typically one that folds into another instruction. For example, reg-to-reg moves can often be skipped by renaming the registers in the CPU, but they still are encoded and thus wouldn't be considered 'free' here.

Enumerator:

TCC_Free	Expected to fold away in lowering.
TCC_Basic	The cost of a typical 'add' instruction.
TCC_Expensive	The cost of a 'div' instruction on x86.

Definition at line 91 of file TargetTransformInfo.h.

Constructor & Destructor Documentation

TargetTransformInfo::~TargetTransformInfo ( ) [pure virtual]

This class is intended to be subclassed by real implementations.

Definition at line 26 of file TargetTransformInfo.cpp.

Member Function Documentation

unsigned TargetTransformInfo::getAddressComputationCost ( Type * Ty ) const [virtual]

Returns:: The cost of the address computation. For most targets this can be merged into the instruction indexing mode. Some targets might want to distinguish between address computation for memory operations on vector types and scalar types. Such targets should override this function.

Definition at line 201 of file TargetTransformInfo.cpp.

References getAddressComputationCost(), and PrevTTI.

Referenced by getAddressComputationCost().

void TargetTransformInfo::getAnalysisUsage ( AnalysisUsage & AU ) const [protected, virtual]

All pass subclasses must call TargetTransformInfo::getAnalysisUsage.

Definition at line 48 of file TargetTransformInfo.cpp.

References llvm::AnalysisUsage::addRequired().

unsigned TargetTransformInfo::getArithmeticInstrCost	(	unsigned	Opcode,
		Type *	Ty,
		OperandValueKind	Opd1Info = `OK_AnyValue`,
		OperandValueKind	Opd2Info = `OK_AnyValue`
	)		const `[virtual]`

Returns:: The expected cost of arithmetic ops, such as mul, xor, fsub, etc.

Definition at line 152 of file TargetTransformInfo.cpp.

References getArithmeticInstrCost(), and PrevTTI.

Referenced by getArithmeticInstrCost().

unsigned TargetTransformInfo::getCallCost	(	FunctionType *	FTy,
		int	NumArgs = `-1`
	)		const `[virtual]`

Estimate the cost of a function call when lowered.

The contract for this is the same as getOperationCost except that it supports an interface that provides extra information specific to call instructions.

This is the most basic query for estimating call cost: it only knows the function type and (potentially) the number of arguments at the call site. The latter is only interesting for varargs function types.

Definition at line 62 of file TargetTransformInfo.cpp.

References getCallCost(), and PrevTTI.

Referenced by getCallCost().

unsigned TargetTransformInfo::getCallCost	(	const Function *	F,
		int	NumArgs = `-1`
	)		const `[virtual]`

Estimate the cost of calling a specific function when lowered.

This overload adds the ability to reason about the particular function being called in the event it is a library call with special lowering.

Definition at line 67 of file TargetTransformInfo.cpp.

References getCallCost(), and PrevTTI.

unsigned TargetTransformInfo::getCallCost	(	const Function *	F,
		ArrayRef< const Value * >	Arguments
	)		const `[virtual]`

Estimate the cost of calling a specific function when lowered.

This overload allows specifying a set of candidate argument values.

Definition at line 72 of file TargetTransformInfo.cpp.

References getCallCost(), and PrevTTI.

unsigned TargetTransformInfo::getCastInstrCost	(	unsigned	Opcode,
		Type *	Dst,
		Type *	Src
	)		const `[virtual]`

Returns:: The expected cost of cast instructions, such as bitcast, trunc, zext, etc.

Definition at line 164 of file TargetTransformInfo.cpp.

References getCastInstrCost(), and PrevTTI.

Referenced by getCastInstrCost().

unsigned TargetTransformInfo::getCFInstrCost ( unsigned Opcode ) const [virtual]

Returns:: The expected cost of control-flow related instructions such as Phi, Ret, Br.

Definition at line 169 of file TargetTransformInfo.cpp.

References getCFInstrCost(), and PrevTTI.

Referenced by getCFInstrCost().

unsigned TargetTransformInfo::getCmpSelInstrCost	(	unsigned	Opcode,
		Type *	ValTy,
		Type *	CondTy = `0`
	)		const `[virtual]`

Returns:: The expected cost of compare and select instructions.

Definition at line 173 of file TargetTransformInfo.cpp.

References getCmpSelInstrCost(), and PrevTTI.

Referenced by getCmpSelInstrCost().

unsigned TargetTransformInfo::getGEPCost	(	const Value *	Ptr,
		ArrayRef< const Value * >	Operands
	)		const `[virtual]`

Estimate the cost of a GEP operation when lowered.

The contract for this function is the same as getOperationCost except that it supports an interface that provides extra information specific to the GEP operation.

Definition at line 57 of file TargetTransformInfo.cpp.

References getGEPCost(), and PrevTTI.

Referenced by getGEPCost().

unsigned TargetTransformInfo::getIntImmCost	(	const APInt &	Imm,
		Type *	Ty
	)		const `[virtual]`

getIntImmCost - Return the expected cost of materializing the given integer immediate of the specified type.

Definition at line 136 of file TargetTransformInfo.cpp.

References getIntImmCost(), and PrevTTI.

Referenced by getIntImmCost(), and getMemsetStringVal().

unsigned TargetTransformInfo::getIntrinsicCost	(	Intrinsic::ID	IID,
		Type *	RetTy,
		ArrayRef< Type * >	ParamTys
	)		const `[virtual]`

Estimate the cost of an intrinsic when lowered.

Mirrors the getCallCost method but uses an intrinsic identifier.

Definition at line 77 of file TargetTransformInfo.cpp.

References getIntrinsicCost(), and PrevTTI.

Referenced by getIntrinsicCost().

unsigned TargetTransformInfo::getIntrinsicCost	(	Intrinsic::ID	IID,
		Type *	RetTy,
		ArrayRef< const Value * >	Arguments
	)		const `[virtual]`

Estimate the cost of an intrinsic when lowered.

Mirrors the getCallCost method but uses an intrinsic identifier.

Definition at line 82 of file TargetTransformInfo.cpp.

References getIntrinsicCost(), and PrevTTI.

unsigned TargetTransformInfo::getIntrinsicInstrCost	(	Intrinsic::ID	ID,
		Type *	RetTy,
		ArrayRef< Type * >	Tys
	)		const `[virtual]`

Returns:: The cost of Intrinsic instructions.

Definition at line 191 of file TargetTransformInfo.cpp.

References getIntrinsicInstrCost(), and PrevTTI.

Referenced by getIntrinsicInstrCost().

unsigned TargetTransformInfo::getJumpBufAlignment ( ) const [virtual]

getJumpBufAlignment - returns the target's jmp_buf alignment in bytes

Definition at line 119 of file TargetTransformInfo.cpp.

References getJumpBufAlignment(), and PrevTTI.

Referenced by getJumpBufAlignment().

unsigned TargetTransformInfo::getJumpBufSize ( ) const [virtual]

getJumpBufSize - returns the target's jmp_buf size in bytes.

Definition at line 123 of file TargetTransformInfo.cpp.

References getJumpBufSize(), and PrevTTI.

Referenced by getJumpBufSize().

unsigned TargetTransformInfo::getMaximumUnrollFactor ( ) const [virtual]

Returns:: The maximum unroll factor that the vectorizer should try to perform for this target. This number depends on the level of parallelism and the number of execution units in the CPU.

Definition at line 148 of file TargetTransformInfo.cpp.

References getMaximumUnrollFactor(), and PrevTTI.

Referenced by getMaximumUnrollFactor().

unsigned TargetTransformInfo::getMemoryOpCost	(	unsigned	Opcode,
		Type *	Src,
		unsigned	Alignment,
		unsigned	AddressSpace
	)		const `[virtual]`

Returns:: The cost of Load and Store instructions.

Definition at line 183 of file TargetTransformInfo.cpp.

References getMemoryOpCost(), and PrevTTI.

Referenced by getMemoryOpCost().

unsigned TargetTransformInfo::getNumberOfParts ( Type * Tp ) const [virtual]

Returns:: The number of pieces into which the provided type must be split during legalization. Zero is returned when the answer is unknown.

Definition at line 197 of file TargetTransformInfo.cpp.

References getNumberOfParts(), and PrevTTI.

Referenced by getNumberOfParts().

unsigned TargetTransformInfo::getNumberOfRegisters ( bool Vector ) const [virtual]

Returns:: The number of scalar or vector registers that the target has. If 'Vectors' is true, it returns the number of vector registers. If it is set to false, it returns the number of scalar registers.

Definition at line 140 of file TargetTransformInfo.cpp.

References getNumberOfRegisters(), and PrevTTI.

Referenced by getNumberOfRegisters().

unsigned TargetTransformInfo::getOperationCost	(	unsigned	Opcode,
		Type *	Ty,
		Type *	OpTy = `0`
	)		const `[virtual]`

Estimate the cost of a specific operation when lowered.

Note that this is designed to work on an arbitrary synthetic opcode, and thus work for hypothetical queries before an instruction has even been formed. However, this does *not* work for GEPs, and must not be called for a GEP instruction. Instead, use the dedicated getGEPCost interface as analyzing a GEP's cost required more information.

Typically only the result type is required, and the operand type can be omitted. However, if the opcode is one of the cast instructions, the operand type is required.

The returned cost is defined in terms of TargetCostConstants, see its comments for a detailed explanation of the cost values.

Definition at line 52 of file TargetTransformInfo.cpp.

References getOperationCost(), and PrevTTI.

Referenced by getOperationCost().

TargetTransformInfo::PopcntSupportKind TargetTransformInfo::getPopcntSupport ( unsigned IntTyWidthInBit ) const [virtual]

getPopcntSupport - Return hardware support for population count.

Definition at line 132 of file TargetTransformInfo.cpp.

References getPopcntSupport(), and PrevTTI.

Referenced by getPopcntSupport().

unsigned TargetTransformInfo::getRegisterBitWidth ( bool Vector ) const [virtual]

Returns:: The width of the largest scalar or vector register type.

Definition at line 144 of file TargetTransformInfo.cpp.

References getRegisterBitWidth(), and PrevTTI.

Referenced by getRegisterBitWidth().

unsigned TargetTransformInfo::getShuffleCost	(	ShuffleKind	Kind,
		Type *	Tp,
		int	Index = `0`,
		Type *	SubTp = `0`
	)		const `[virtual]`

Returns:: The cost of a shuffle instruction of kind Kind and of type Tp. The index and subtype parameters are used by the subvector insertion and extraction shuffle kinds.

Definition at line 159 of file TargetTransformInfo.cpp.

References getShuffleCost(), and PrevTTI.

Referenced by getShuffleCost().

unsigned TargetTransformInfo::getUserCost ( const User * U ) const [virtual]

Estimate the cost of a given IR user when lowered.

This can estimate the cost of either a ConstantExpr or Instruction when lowered. It has two primary advantages over the getOperationCost and getGEPCost above, and one significant disadvantage: it can only be used when the IR construct has already been formed.

The advantages are that it can inspect the SSA use graph to reason more accurately about the cost. For example, all-constant-GEPs can often be folded into a load or other instruction, but if they are used in some other context they may not be folded. This routine can distinguish such cases.

The returned cost is defined in terms of TargetCostConstants, see its comments for a detailed explanation of the cost values.

Definition at line 87 of file TargetTransformInfo.cpp.

References getUserCost(), and PrevTTI.

Referenced by llvm::CodeMetrics::analyzeBasicBlock(), and getUserCost().

unsigned TargetTransformInfo::getVectorInstrCost	(	unsigned	Opcode,
		Type *	Val,
		unsigned	Index = `-1`
	)		const `[virtual]`

Returns:: The expected cost of vector Insert and Extract. Use -1 to indicate that there is no information on the index value.

Definition at line 178 of file TargetTransformInfo.cpp.

References getVectorInstrCost(), and PrevTTI.

Referenced by getVectorInstrCost().

bool TargetTransformInfo::isLegalAddImmediate ( int64_t Imm ) const [virtual]

isLegalAddImmediate - Return true if the specified immediate is legal add immediate, that is the target has add instructions which can add a register with the immediate without having to materialize the immediate into a register.

Definition at line 95 of file TargetTransformInfo.cpp.

References isLegalAddImmediate(), and PrevTTI.

Referenced by isLegalAddImmediate().

bool TargetTransformInfo::isLegalAddressingMode	(	Type *	Ty,
		GlobalValue *	BaseGV,
		int64_t	BaseOffset,
		bool	HasBaseReg,
		int64_t	Scale
	)		const `[virtual]`

isLegalAddressingMode - Return true if the addressing mode represented by AM is legal for this target, for a load/store of the specified type. The type may be VoidTy, in which case only return true if the addressing mode is legal for a load/store of any legal type. TODO: Handle pre/postinc as well.

Definition at line 103 of file TargetTransformInfo.cpp.

References isLegalAddressingMode(), and PrevTTI.

Referenced by isLegalAddressingMode(), and isLegalUse().

bool TargetTransformInfo::isLegalICmpImmediate ( int64_t Imm ) const [virtual]

isLegalICmpImmediate - Return true if the specified immediate is legal icmp immediate, that is the target has icmp instructions which can compare a register against the immediate without having to materialize the immediate into a register.

Definition at line 99 of file TargetTransformInfo.cpp.

References isLegalICmpImmediate(), and PrevTTI.

Referenced by isLegalICmpImmediate(), and isLegalUse().

bool TargetTransformInfo::isLoweredToCall ( const Function * F ) const [virtual]

Test whether calls to a function lower to actual program function calls.

The idea is to test whether the program is likely to require a 'call' instruction or equivalent in order to call the given function.

FIXME: It's not clear that this is a good or useful query API. Client's should probably move to simpler cost metrics using the above. Alternatively, we could split the cost interface into distinct code-size and execution-speed costs. This would allow modelling the core of this query more accurately as the a call is a single small instruction, but incurs significant execution cost.

Definition at line 91 of file TargetTransformInfo.cpp.

References isLoweredToCall(), and PrevTTI.

Referenced by llvm::CodeMetrics::analyzeBasicBlock(), and isLoweredToCall().

bool TargetTransformInfo::isTruncateFree	(	Type *	Ty1,
		Type *	Ty2
	)		const `[virtual]`

isTruncateFree - Return true if it's free to truncate a value of type Ty1 to type Ty2. e.g. On x86 it's free to truncate a i32 value in register EAX to i16 by referencing its sub-register AX.

Definition at line 111 of file TargetTransformInfo.cpp.

References isTruncateFree(), and PrevTTI.

Referenced by isTruncateFree(), and llvm::SCEVExpander::replaceCongruentIVs().

bool TargetTransformInfo::isTypeLegal ( Type * Ty ) const [virtual]

Is this type legal.

Definition at line 115 of file TargetTransformInfo.cpp.

References isTypeLegal(), and PrevTTI.

Referenced by isTypeLegal(), and ShouldBuildLookupTable().

void TargetTransformInfo::popTTIStack ( ) [protected]

All pass subclasses must in their finalizePass routine call popTTIStack to update the pointers tracking the previous TTI instance in the analysis group's stack, and the top of the analysis group's stack.

Definition at line 38 of file TargetTransformInfo.cpp.

References PrevTTI, and TopTTI.

void TargetTransformInfo::pushTTIStack ( Pass * P ) [protected]

All pass subclasses must in their initializePass routine call pushTTIStack with themselves to update the pointers tracking the previous TTI instance in the analysis group's stack, and the top of the analysis group's stack.

Definition at line 29 of file TargetTransformInfo.cpp.

References llvm::Pass::getAnalysis(), PrevTTI, and TopTTI.

bool TargetTransformInfo::shouldBuildLookupTables ( ) const [virtual]

shouldBuildLookupTables - Return true if switches should be turned into lookup tables for the target.

Definition at line 127 of file TargetTransformInfo.cpp.

References PrevTTI, and shouldBuildLookupTables().

Referenced by shouldBuildLookupTables(), and SwitchToLookupTable().

Member Data Documentation

char TargetTransformInfo::ID = 0 [static]

Analysis group identification.

Definition at line 337 of file TargetTransformInfo.h.

TargetTransformInfo* llvm::TargetTransformInfo::PrevTTI [protected]

The TTI instance one level down the stack.

This is used to implement the default behavior all of the methods which is to delegate up through the stack of TTIs until one can answer the query.

Definition at line 45 of file TargetTransformInfo.h.

Referenced by getAddressComputationCost(), getArithmeticInstrCost(), getCallCost(), getCastInstrCost(), getCFInstrCost(), getCmpSelInstrCost(), getGEPCost(), getIntImmCost(), getIntrinsicCost(), getIntrinsicInstrCost(), getJumpBufAlignment(), getJumpBufSize(), getMaximumUnrollFactor(), getMemoryOpCost(), getNumberOfParts(), getNumberOfRegisters(), getOperationCost(), getPopcntSupport(), getRegisterBitWidth(), getShuffleCost(), getUserCost(), getVectorInstrCost(), isLegalAddImmediate(), isLegalAddressingMode(), isLegalICmpImmediate(), isLoweredToCall(), isTruncateFree(), isTypeLegal(), popTTIStack(), pushTTIStack(), and shouldBuildLookupTables().

TargetTransformInfo* llvm::TargetTransformInfo::TopTTI [protected]

The top of the stack of TTI analyses available.

This is a convenience routine maintained as TTI analyses become available that complements the PrevTTI delegation chain. When one part of an analysis pass wants to query another part of the analysis pass it can use this to start back at the top of the stack.

Definition at line 53 of file TargetTransformInfo.h.

Referenced by popTTIStack(), and pushTTIStack().

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

Public Member Functions

Static Public Attributes

Protected Member Functions

Protected Attributes

Generic Target Information

Scalar Target Information

Vector Target Information

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation