#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 1979 of file TargetLowering.h.

Constructor & Destructor Documentation

llvm::TargetLowering::TargetLoweringOpt::TargetLoweringOpt	(	SelectionDAG &	InDAG,
		bool	LT,
		bool	LO
	)		`[inline, explicit]`

Definition at line 1986 of file TargetLowering.h.

Member Function Documentation

bool llvm::TargetLowering::TargetLoweringOpt::CombineTo	(	SDValue	O,
		SDValue	N
	)		`[inline]`

Definition at line 1993 of file TargetLowering.h.

References New, and Old.

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

bool llvm::TargetLowering::TargetLoweringOpt::LegalOperations ( ) const [inline]

Definition at line 1991 of file TargetLowering.h.

References LegalOps.

bool llvm::TargetLowering::TargetLoweringOpt::LegalTypes ( ) const [inline]

Definition at line 1990 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 283 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 322 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::EVT::isVector(), llvm::TargetLoweringBase::isZExtFree(), llvm::NextPowerOf2(), llvm::ISD::TRUNCATE, llvm::X, and llvm::ISD::ZERO_EXTEND.