org.jikesrvm.osr

Class EncodedOSRMap

java.lang.Object

org.jikesrvm.osr.EncodedOSRMap

public final class EncodedOSRMap
extends Object

EncodedOSRMap provides the similar function as GC map in OptMachineCodeMap.

In OptCompiledMethod, an instance of this class will represent all OSR map info for that method.

Field Summary

Fields

Modifier and Type	Field and Description
private static EncodedOSRMap	emptyMap map used when there are no OSR instructions
private int	lastEntry the last entry index.
private long[]	mapEntries osr info entries
private int[]	osrMaps the OSR map

Constructor Summary

Constructors

Modifier	Constructor and Description
private	EncodedOSRMap() Constructor to build empty map
private	EncodedOSRMap(VariableMap varMap, MachineCodeOffsets mcOffsets)

Method Summary

Modifier and Type	Method and Description
private void	_generateMapForOneMethodVariable(ArrayList<Integer> tempOsrMaps, int regMapIndex, MethodVariables mVar, boolean lastMid) Generate value in the Osr map
private int	findOSREntry(Offset mcOffset) Do a binary search, find the entry for the machine code offset.
private int	generateOsrMaps(ArrayList<Integer> tempOsrMaps, LinkedList<MethodVariables> mVarList) Generate value in the Osr map, return the index of the first integer in the map.
private int	getBCIndex(int entry)
int	getBytecodeIndexForMCOffset(Offset mcOffset) Get bytecode index for a given instruction offset in bytes.
private int	getIEIndex(int entry)
int	getInlineEncodingForMCOffset(Offset mcOffset)
int[]	getMCIndexes()
private int	getMCOffset(int entry)
private int	getOSRMapIndex(int entry)
OSRMapIterator	getOsrMapIteratorForMCOffset(Offset mcOffset) given a MC offset, return an iterator over the elements of this map.
private static int	getRegBitPosition(int regnum)
int	getRegisterMapForMCOffset(Offset mcOffset) Gets register's reference map for the machine instruction offset
boolean	hasOSRMap(Offset mcOffset)
static EncodedOSRMap	makeMap(VariableMap varMap, MachineCodeOffsets mcOffsets) Encodes the given variable map as OSRMap.
void	printMap() print the encoded map for debugging.
private void	processTuple(ArrayList<Integer> tempOsrMaps, LocalRegPair tuple, boolean isLast) Process a 32-bit tuple.
static boolean	registerIsSet(int map, int regnum)
private void	setBCIndex(int entry, int index)
private void	setIEIndex(int entry, int index)
private void	setMCOffset(int entry, int offset)
private void	setOSRMapIndex(int entry, int index)
private static int	setRegister(int map, int regnum) Marks a register as a reference type.
private void	translateMap(ArrayList<Integer> tempOsrMaps, LinkedList<VariableMapElement> osrlist, MachineCodeOffsets mcOffsets) Translates a list of OSR_MapElement to encoding.

Methods inherited from class java.lang.Object

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

Field Detail

mapEntries

private final long[] mapEntries

osr info entries

lastEntry

private final int lastEntry

the last entry index.

osrMaps

private final int[] osrMaps

the OSR map

emptyMap

private static final EncodedOSRMap emptyMap

map used when there are no OSR instructions

Constructor Detail

EncodedOSRMap

private EncodedOSRMap()

Constructor to build empty map

EncodedOSRMap

private EncodedOSRMap(VariableMap varMap,
                      MachineCodeOffsets mcOffsets)

Parameters:

varMap - the variable map to use for building the EncodedOSRMap

mcOffsets - the machine code offsets for the instructions

Method Detail

registerIsSet

public static boolean registerIsSet(int map,
                                    int regnum)

setRegister

private static int setRegister(int map,
                               int regnum)

Marks a register as a reference type.

Parameters:

map - the map

regnum - the register's number

Returns:

the updated map

getRegBitPosition

private static int getRegBitPosition(int regnum)

makeMap

public static EncodedOSRMap makeMap(VariableMap varMap,
                                    MachineCodeOffsets mcOffsets)

Encodes the given variable map as OSRMap.

Parameters:

varMap - the variable map to encode

mcOffsets - machine code offsets for the instructions

Returns:

the canonical empty map if the map is empty, an encoded osr map otherwise

translateMap

private void translateMap(ArrayList<Integer> tempOsrMaps,
                          LinkedList<VariableMapElement> osrlist,
                          MachineCodeOffsets mcOffsets)

Translates a list of OSR_MapElement to encoding.

we can not trust the osrlist is in the increasing order of machine code offset. Sort it first.

Parameters:

tempOsrMaps - an empty list that will hold temporary OSR map information

osrlist - information about instructions and variables

mcOffsets - machine code offsets for the instructions

generateOsrMaps

private int generateOsrMaps(ArrayList<Integer> tempOsrMaps,
                            LinkedList<MethodVariables> mVarList)

Generate value in the Osr map, return the index of the first integer in the map.

An OSR Map has following structure:

 | regmap || mid, mpc, (n1, n2) ... ||
          || mid, mpc, (n1, n2) ... ||
 

Regmap indicates the value of which register is a reference, the execution state extractor can convert the value to an object to avoid confusing GC. The MSB of regmap indicates next mid is valid.

The MSB of mid indicates if the next mid item will be available.

The MSB of mpc indicates if the next is a valid pair

Parameters:

tempOsrMaps - temporary OSR map information. This method will fill this data structure.

mVarList - information about variables

Returns:

the index of the first integer in the map

_generateMapForOneMethodVariable

private void _generateMapForOneMethodVariable(ArrayList<Integer> tempOsrMaps,
                                              int regMapIndex,
                                              MethodVariables mVar,
                                              boolean lastMid)

Generate value in the Osr map

Parameters:

tempOsrMaps - the maps under construction

regMapIndex - used to patch the register map

mVar - the method variables

lastMid - whether this is the last method in the inlined chain

processTuple

private void processTuple(ArrayList<Integer> tempOsrMaps,
                          LocalRegPair tuple,
                          boolean isLast)

Process a 32-bit tuple.

Parameters:

tempOsrMaps - the temporary osr maps

tuple - mapping of the local to register

isLast - whether to set OSRConstants.NEXT_BIT

hasOSRMap

public boolean hasOSRMap(Offset mcOffset)

Parameters:

mcOffset - the machine instruction offset

Returns:

whether there's an OSR map exist for the machine instruction offset

getBytecodeIndexForMCOffset

public int getBytecodeIndexForMCOffset(Offset mcOffset)

Get bytecode index for a given instruction offset in bytes.

NOTE: It is the caller's reponsibility to make sure there are OSR entry exist for a machine instruction offset.

Parameters:

mcOffset - the instruction offset in bytes

Returns:

the bytecode index

getInlineEncodingForMCOffset

public int getInlineEncodingForMCOffset(Offset mcOffset)

getRegisterMapForMCOffset

public int getRegisterMapForMCOffset(Offset mcOffset)

Gets register's reference map for the machine instruction offset

Parameters:

mcOffset - the instruction offset in bytes

Returns:

the desired OSR map

getOsrMapIteratorForMCOffset

public OSRMapIterator getOsrMapIteratorForMCOffset(Offset mcOffset)

given a MC offset, return an iterator over the elements of this map.

NOTE: the map index is gotten from 'findOSRMapIndex'. This has to be changed....

Parameters:

mcOffset - the instruction offset in bytes

Returns:

an iterator

findOSREntry

private int findOSREntry(Offset mcOffset)

Do a binary search, find the entry for the machine code offset.

Parameters:

mcOffset - the instruction offset in bytes

Returns:

OSRConstants.NO_OSR_ENTRY if no entry was found, the entry otherwise

getMCOffset

private int getMCOffset(int entry)

getOSRMapIndex

private int getOSRMapIndex(int entry)

getBCIndex

private int getBCIndex(int entry)

getIEIndex

private int getIEIndex(int entry)

setMCOffset

private void setMCOffset(int entry,
                         int offset)

setOSRMapIndex

private void setOSRMapIndex(int entry,
                            int index)

setBCIndex

private void setBCIndex(int entry,
                        int index)

setIEIndex

private void setIEIndex(int entry,
                        int index)

printMap

public void printMap()

print the encoded map for debugging.

getMCIndexes

public int[] getMCIndexes()