com.oracle.graal.lir

Class RedundantMoveElimination.Optimization

java.lang.Object

com.oracle.graal.lir.RedundantMoveElimination.Optimization

Enclosing class:

RedundantMoveElimination

private static final class RedundantMoveElimination.Optimization
extends Object

Field Summary

Fields

Modifier and Type	Field and Description
(package private) Map<AbstractBlockBase<?>,RedundantMoveElimination.BlockData>	blockData
(package private) Register[]	callerSaveRegs
private static int	COMPLEXITY_LIMIT The maximum number of locations * blocks.
(package private) int[]	eligibleRegs Contains the register number for registers which can be optimized and -1 for the others.
private FrameMap	frameMap
(package private) static int	INIT_VALUE
(package private) int	numRegs
(package private) Map<Integer,Integer>	stackIndices A map from the StackSlot offset to an index into the state.

Constructor Summary

Constructors

Constructor and Description
Optimization(FrameMap frameMap)

Method Summary

Modifier and Type	Method and Description
private static void	clearValues(int[] state, int defNum)
private static void	clearValuesOfKindObject(int[] state, int defNum)
private static void	copyState(int[] dest, int[] source)
private void	doOptimize(LIR lir) The main method doing the elimination of redundant moves.
private void	eliminateMoves(LIR lir) Deletes all move instructions where the target location already contains the source value.
private static int	encodeValueNum(int valueNum, boolean isObjectKind) Encodes a value number + the is-object information to a number to be stored in a state.
private int	getOffset(StackSlot stackSlot)
private int	getStateIdx(Value location) Returns the index to the state arrays in BlockData for a specific location.
private void	initBlockData(LIR lir)
private static boolean	isEligibleMove(LIRInstruction op) Returns true for a move instruction which is a candidate for elimination.
private static boolean	isObjectValue(int encodedValueNum) Returns true if an encoded value number (which is stored in a state) refers to an object reference.
private static boolean	mergeState(int[] dest, int[] source, int defNum) The state merge function for dataflow joins.
private boolean	solveDataFlow(LIR lir) Calculates the entry and exit states for all basic blocks.
private int	updateState(int[] state, LIRInstruction op, int initValueNum) Updates the state for one instruction.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

blockData

Map<AbstractBlockBase<?>,RedundantMoveElimination.BlockData> blockData

callerSaveRegs

Register[] callerSaveRegs

eligibleRegs

int[] eligibleRegs

Contains the register number for registers which can be optimized and -1 for the others.

stackIndices

Map<Integer,Integer> stackIndices

A map from the StackSlot offset to an index into the state. StackSlots of different kinds that map to the same location will map to the same index.

numRegs

int numRegs

frameMap

private final FrameMap frameMap

INIT_VALUE

static final int INIT_VALUE

See Also:

Constant Field Values

COMPLEXITY_LIMIT

private static final int COMPLEXITY_LIMIT

The maximum number of locations * blocks. This is a complexity limit for the inner loop in mergeState(int[], int[], int) (assuming a small number of iterations in solveDataFlow(com.oracle.graal.lir.LIR).

See Also:

Constant Field Values

Constructor Detail

Optimization

public Optimization(FrameMap frameMap)

Method Detail

doOptimize

private void doOptimize(LIR lir)

The main method doing the elimination of redundant moves.

initBlockData

private void initBlockData(LIR lir)

getOffset

private int getOffset(StackSlot stackSlot)

solveDataFlow

private boolean solveDataFlow(LIR lir)

Calculates the entry and exit states for all basic blocks.

Returns:

Returns true on success and false if the the control flow is too complex.

eliminateMoves

private void eliminateMoves(LIR lir)

Deletes all move instructions where the target location already contains the source value.

updateState

private int updateState(int[] state,
                        LIRInstruction op,
                        int initValueNum)

Updates the state for one instruction.

mergeState

private static boolean mergeState(int[] dest,
                                  int[] source,
                                  int defNum)

The state merge function for dataflow joins.

copyState

private static void copyState(int[] dest,
                              int[] source)

clearValues

private static void clearValues(int[] state,
                                int defNum)

clearValuesOfKindObject

private static void clearValuesOfKindObject(int[] state,
                                            int defNum)

getStateIdx

private int getStateIdx(Value location)

Returns the index to the state arrays in BlockData for a specific location.

encodeValueNum

private static int encodeValueNum(int valueNum,
                                  boolean isObjectKind)

Encodes a value number + the is-object information to a number to be stored in a state.

isObjectValue

private static boolean isObjectValue(int encodedValueNum)

Returns true if an encoded value number (which is stored in a state) refers to an object reference.

isEligibleMove

private static boolean isEligibleMove(LIRInstruction op)

Returns true for a move instruction which is a candidate for elimination.