#include <TargetLowering.h>

Collaboration diagram for llvm::TargetLowering::TargetLoweringOpt:

Public Member Functions
	TargetLoweringOpt (SelectionDAG &InDAG, bool LT, bool LO)

bool	LegalTypes () const

bool	LegalOperations () const

bool	CombineTo (SDValue O, SDValue N)

bool	ShrinkDemandedConstant (SDValue Op, const APInt &Demanded)

bool	ShrinkDemandedOp (SDValue Op, unsigned BitWidth, const APInt &Demanded, SDLoc dl)

Public Attributes
SelectionDAG &	DAG

bool	LegalTys

bool	LegalOps

SDValue	Old

SDValue	New

Detailed Description

A convenience struct that encapsulates a DAG, and two SDValues for returning information from TargetLowering to its clients that want to combine.

Definition at line 1771 of file TargetLowering.h.

Constructor & Destructor Documentation

llvm::TargetLowering::TargetLoweringOpt::TargetLoweringOpt	(	SelectionDAG &	InDAG,
		bool	LT,
		bool	LO
	)

inlineexplicit

Definition at line 1778 of file TargetLowering.h.

Member Function Documentation

bool llvm::TargetLowering::TargetLoweringOpt::CombineTo	(	SDValue	O,
		SDValue	N
	)

inline

Definition at line 1785 of file TargetLowering.h.

References N, New, and Old.

Referenced by llvm::TargetLowering::SimplifyDemandedBits().

bool llvm::TargetLowering::TargetLoweringOpt::LegalOperations ( ) const

inline

Definition at line 1783 of file TargetLowering.h.

References LegalOps.

bool llvm::TargetLowering::TargetLoweringOpt::LegalTypes ( ) const

inline

Definition at line 1782 of file TargetLowering.h.

References LegalTys.

bool TargetLowering::TargetLoweringOpt::ShrinkDemandedConstant	(	SDValue	Op,
		const APInt &	Demanded
	)

Check to see if the specified operand of the specified instruction is a constant integer. If so, check to see if there are any bits set in the constant that are not demanded. If so, shrink the constant and return true.

ShrinkDemandedConstant - Check to see if the specified operand of the specified instruction is a constant integer. If so, check to see if there are any bits set in the constant that are not demanded. If so, shrink the constant and return true.

Definition at line 281 of file TargetLowering.cpp.

References llvm::ISD::AND, llvm::CallingConv::C, llvm::dyn_cast(), llvm::ConstantSDNode::getAPIntValue(), llvm::SDValue::getNode(), llvm::SDValue::getOpcode(), llvm::SDValue::getOperand(), llvm::SDValue::getValueType(), llvm::APInt::intersects(), llvm::ISD::OR, and llvm::ISD::XOR.

Referenced by llvm::TargetLowering::SimplifyDemandedBits().

bool TargetLowering::TargetLoweringOpt::ShrinkDemandedOp	(	SDValue	Op,
		unsigned	BitWidth,
		const APInt &	Demanded,
		SDLoc	dl
	)

Convert x+y to (VT)((SmallVT)x+(SmallVT)y) if the casts are free. This uses isZExtFree and ZERO_EXTEND for the widening cast, but it could be generalized for targets with other types of implicit widening casts.

ShrinkDemandedOp - Convert x+y to (VT)((SmallVT)x+(SmallVT)y) if the casts are free. This uses isZExtFree and ZERO_EXTEND for the widening cast, but it could be generalized for targets with other types of implicit widening casts.

Definition at line 320 of file TargetLowering.cpp.

References llvm::ISD::ANY_EXTEND, llvm::APInt::countLeadingZeros(), llvm::EVT::getIntegerVT(), llvm::SDValue::getNode(), llvm::SDValue::getNumOperands(), llvm::SDNode::getNumValues(), llvm::SDValue::getOpcode(), llvm::SDNode::getOperand(), llvm::SDValue::getValueType(), llvm::SDNode::hasOneUse(), llvm::isPowerOf2_32(), llvm::TargetLoweringBase::isTruncateFree(), llvm::TargetLoweringBase::isZExtFree(), llvm::NextPowerOf2(), llvm::ISD::TRUNCATE, llvm::X, and llvm::ISD::ZERO_EXTEND.