llvm::Rematerializer::Reg Struct Reference

A rematerializable register defined by a single machine instruction. More...

#include "llvm/CodeGen/Rematerializer.h"

Classes
struct	Dependency
	A read register operand of DefMI that is rematerializable (according to the rematerializer). More...

Public Types
using	RegionUsers = SmallDenseSet<MachineInstr *, 4>

Public Member Functions
Register	getDefReg () const
	Returns the rematerializable register from its defining instruction.
bool	hasUsersInDefRegion () const
bool	hasUsersOutsideDefRegion () const
std::pair< MachineInstr *, MachineInstr * >	getRegionUseBounds (unsigned UseRegion, const LiveIntervals &LIS) const
	Returns the first and last user of the register in region UseRegion.
bool	isAlive () const

Public Attributes
MachineInstr *	DefMI
	Single MI defining the rematerializable register.
unsigned	DefRegion
	Defining region of DefMI.
LaneBitmask	Mask
	The rematerializable register's lane bitmask.
SmallDenseMap< unsigned, RegionUsers, 2 >	Uses
	Uses of the register, mapped by region.
SmallVector< Dependency, 2 >	Dependencies
	This register's rematerializable dependencies, one per unique rematerializable register operand.

Detailed Description

A rematerializable register defined by a single machine instruction.

A rematerializable register has a set of dependencies, which correspond to the unique read register operands of its defining instruction. They are identified by their machine operand index, and can themselves be rematerializable. Operand indices corresponding to unrematerializable dependencies are managed by and queried from the rematerializer.

A rematerializable register also has an arbitrary number of users in an arbitrary number of regions, potentially including its own defining region. When rematerializations lead to operand changes in users, a register may find itself without any user left, at which point the rematerializer marks it for deletion. Its defining instruction either becomes nullptr (without rollback support) or its opcode is set to TargetOpcode::DBG_VALUE (with rollback support) until Rematerializer::commitRematerializations is called.

Definition at line 128 of file Rematerializer.h.

Member Typedef Documentation

RegionUsers

using llvm::Rematerializer::Reg::RegionUsers = SmallDenseSet<MachineInstr *, 4>

Definition at line 136 of file Rematerializer.h.

Member Function Documentation

getDefReg()

Register llvm::Rematerializer::Reg::getDefReg ( ) const

inline

Returns the rematerializable register from its defining instruction.

Definition at line 156 of file Rematerializer.h.

References assert(), and DefMI.

Referenced by llvm::Rematerializer::printID(), llvm::Rematerializer::printRematReg(), and llvm::Rematerializer::updateLiveIntervals().

getRegionUseBounds()

std::pair< MachineInstr *, MachineInstr * > Rematerializer::Reg::getRegionUseBounds	(	unsigned	UseRegion,
		const LiveIntervals &	LIS ) const

Returns the first and last user of the register in region UseRegion.

If the register has no user in the region, returns a pair of nullptr's.

Definition at line 638 of file Rematerializer.cpp.

References assert(), and Uses.

Referenced by llvm::Rematerializer::rematerializeToRegion().

hasUsersInDefRegion()

bool llvm::Rematerializer::Reg::hasUsersInDefRegion ( ) const

inline

Definition at line 162 of file Rematerializer.h.

References DefRegion, and Uses.

hasUsersOutsideDefRegion()

bool llvm::Rematerializer::Reg::hasUsersOutsideDefRegion ( ) const

inline

Definition at line 166 of file Rematerializer.h.

References DefRegion, and Uses.

isAlive()

bool llvm::Rematerializer::Reg::isAlive ( ) const

inline

Definition at line 177 of file Rematerializer.h.

References DefMI.

Referenced by llvm::Rematerializer::reviveRegIfDead().

Member Data Documentation

DefMI

MachineInstr* llvm::Rematerializer::Reg::DefMI

Single MI defining the rematerializable register.

Definition at line 130 of file Rematerializer.h.

Referenced by llvm::Rematerializer::findRematInRegion(), getDefReg(), isAlive(), llvm::Rematerializer::printID(), llvm::Rematerializer::printRematReg(), llvm::Rematerializer::reviveRegIfDead(), and llvm::Rematerializer::updateLiveIntervals().

DefRegion

unsigned llvm::Rematerializer::Reg::DefRegion

Defining region of DefMI.

Definition at line 132 of file Rematerializer.h.

Referenced by llvm::Rematerializer::findRematInRegion(), hasUsersInDefRegion(), hasUsersOutsideDefRegion(), llvm::Rematerializer::printID(), llvm::Rematerializer::printRematReg(), and llvm::Rematerializer::reviveRegIfDead().

Dependencies

SmallVector<Dependency, 2> llvm::Rematerializer::Reg::Dependencies

This register's rematerializable dependencies, one per unique rematerializable register operand.

Definition at line 153 of file Rematerializer.h.

Referenced by llvm::Rematerializer::reviveRegIfDead().

Mask

LaneBitmask llvm::Rematerializer::Reg::Mask

The rematerializable register's lane bitmask.

Definition at line 134 of file Rematerializer.h.

Uses

SmallDenseMap<unsigned, RegionUsers, 2> llvm::Rematerializer::Reg::Uses

Uses of the register, mapped by region.

Definition at line 138 of file Rematerializer.h.

Referenced by llvm::Rematerializer::findRematInRegion(), getRegionUseBounds(), hasUsersInDefRegion(), hasUsersOutsideDefRegion(), and llvm::Rematerializer::printRematReg().

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

• include/llvm/CodeGen/Rematerializer.h
• lib/CodeGen/Rematerializer.cpp