#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, DebugLoc dl)
Public Attributes
SelectionDAG &	DAG
bool	LegalTys
bool	LegalOps
SDValue	Old
SDValue	New

Detailed Description

TargetLoweringOpt - 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 1733 of file TargetLowering.h.

Constructor & Destructor Documentation

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

Definition at line 1740 of file TargetLowering.h.

Member Function Documentation

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

Definition at line 1747 of file TargetLowering.h.

References New, and Old.

Referenced by ShrinkDemandedConstant(), and llvm::TargetLowering::SimplifyDemandedBits().

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

Definition at line 1745 of file TargetLowering.h.

References LegalOps.

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

Definition at line 1744 of file TargetLowering.h.

References LegalTys.

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

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 265 of file TargetLowering.cpp.

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

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

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

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 304 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.