OptMachineCodeMap (Jikes RVM API)

java.lang.Object
- org.jikesrvm.compilers.opt.runtimesupport.OptMachineCodeMap

```
public final class OptMachineCodeMap
extends Object
```
A class that encapsulates mapping information about generated machine code. Since there will be an instance of this class with every OptCompiledMethod, we attempt to pack the data into a reasonably small number of bits.
The supported functions are:
- (1) Map from a machine code offset to a GC map (register & stack map).
- (2) Map from machinecode offset to <method, bcIndex> pair. Used for:
  - dynamic linking
  - lazy compilation
  - adaptive system profiling
- (3) Map from a machine code offset to a tree of <method, bcIndex> pairs that encodes the inlining sequence. Used for:
  - IPA
  - stack inspection (print stack trace, security manager, etc).
  - general debugging support.
  - adaptive system profiling
Note: This file contains two types of methods
- 1) methods called during compilation to create the maps
- 2) methods called at GC time (no allocation allowed!)

Field Summary

Fields
Modifier and Type	Field and Description
`private static int`	`BCI_MASK`
`private static int`	`BCI_SHIFT`
`private static int`	`BIG_BCI_IDX_ADJ`
`private static int`	`BIG_BCI_MASK`
`private static int`	`BIG_BCI_SHIFT`
`private static int`	`BIG_CALL_IDX_ADJ`
`private static int`	`BIG_CALL_MASK`
`private static int`	`BIG_CALL_SHIFT`
`private static int`	`BIG_GCI_IDX_ADJ`
`private static int`	`BIG_GCI_MASK`
`private static int`	`BIG_GCI_SHIFT`
`private static int`	`BIG_IEI_IDX_ADJ`
`private static int`	`BIG_IEI_MASK`
`private static int`	`BIG_IEI_SHIFT`
`private static int`	`BIG_INVALID_BCI`
`private static int`	`BIG_INVALID_GCI`
`private static int`	`BIG_INVALID_IEI`
`private static int`	`BIG_OFFSET_IDX_ADJ`
`private static int`	`BIG_OFFSET_MASK`
`private static int`	`BIG_OFFSET_SHIFT`
`private static int`	`CALL_MASK`
`private static int`	`CALL_SHIFT`
`private static OptMachineCodeMap`	`emptyMachineCodeMap` A machine code map when no information is present
`private static int`	`GCI_MASK`
`private static int`	`GCI_SHIFT`
`private int[]`	`gcMaps` array of GC maps as defined by OptGCMap
`private static int`	`HUGE_BCI_IDX_ADJ`
`private static int`	`HUGE_BCI_MASK`
`private static int`	`HUGE_BCI_SHIFT`
`private static int`	`HUGE_CALL_IDX_ADJ`
`private static int`	`HUGE_CALL_MASK`
`private static int`	`HUGE_CALL_SHIFT`
`private static int`	`HUGE_GCI_IDX_ADJ`
`private static int`	`HUGE_GCI_MASK`
`private static int`	`HUGE_GCI_SHIFT`
`private static int`	`HUGE_IEI_IDX_ADJ`
`private static int`	`HUGE_IEI_MASK`
`private static int`	`HUGE_IEI_SHIFT`
`private static int`	`HUGE_INVALID_BCI`
`private static int`	`HUGE_INVALID_GCI`
`private static int`	`HUGE_INVALID_IEI`
`private static int`	`HUGE_OFFSET_IDX_ADJ`
`private static int`	`HUGE_OFFSET_MASK`
`private static int`	`HUGE_OFFSET_SHIFT`
`private static int`	`IEI_MASK`
`private static int`	`IEI_SHIFT`
`int[]`	`inlineEncoding` encoded data as defined by OptEncodedCallSiteTree.
`private static int`	`INVALID_BCI`
`private static int`	`INVALID_GCI`
`private static int`	`INVALID_IEI`
`private static int`	`IS_GUARDED_CALL`
`private static int`	`IS_UNGUARDED_CALL`
`private int[]`	`MCInformation` Hold entries as defined by the constants above.
`private static int`	`OFFSET_MASK`
`private static int`	`OFFSET_SHIFT`
`private static int`	`SIZEOF_BIG_ENTRY`
`private static int`	`SIZEOF_ENTRY`
`private static int`	`SIZEOF_HUGE_ENTRY`
`private static int`	`START_BITS`
`private static int`	`START_OF_BIG_ENTRY`
`private static int`	`START_OF_ENTRY`
`private static int`	`START_OF_HUGE_ENTRY`
`private static int`	`totalMapSize`
`private static int`	`totalMCSize` Running totals for the size of machine code and maps
`private static TypeReference`	`TYPE`

Constructor Summary

Constructors
Modifier Constructor and Description

private OptMachineCodeMap(int[] _MCInformation, int[] _gcMaps, int[] _inlineEncoding)

Constructors
Modifier	Constructor and Description
`private`	`OptMachineCodeMap(int[] _MCInformation, int[] _gcMaps, int[] _inlineEncoding)`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`(package private) static OptMachineCodeMap`	`create(IR ir, int machineCodeSize)` Creates the map, called during compilation
`void`	`dumpMCInformation(boolean DUMP_MAPS)`
`private static void`	`ensureCorrectMapConstruction(MachineCodeOffsets mcOffsets, Instruction instr)` Ensures correct map construction by either correcting oddities or failing immediately in case of errors.
`int`	`findGCMapIndex(Offset MCOffset)` This method searches for the GC map corresponding to the passed machine code offset.
`private int`	`findMCEntry(Offset MCOffset)` Does a binary search of the machine code maps to find the index in MCInformation where the entry for the argument machine code offset starts.
`int`	`gcMapInformation(int index)`
`private static OptMachineCodeMap`	`generateMCInformation(GCIRMap irMap, boolean DUMP_MAPS, MachineCodeOffsets mcOffsets)` This method walks the IR map, and for each entry it creates the machine code mapping information for the entry.
`private int`	`getBytecodeIndex(int entry)` Returns the Bytecode index for the entry passed
`int`	`getBytecodeIndexForMCOffset(Offset MCOffset)` Get the bytecode index for a machine instruction offset.
`private int`	`getCallInfo(int entry)` Returns the call info for the entry passed.
`private int`	`getGCMapIndex(int entry)` Returns the GC map index for the entry passed
`int`	`getInlineEncodingForMCOffset(Offset MCOffset)` Return the inlining encoding index for the machine instruction offset.
`private int`	`getInlineEncodingIndex(int entry)` Returns the inline encoding index for the entry passed.
`private int`	`getMCOffset(int entry)` Returns the MCOffset for the entry passed
`NormalMethod`	`getMethodForMCOffset(Offset MCOffset)` Get the RVMMethod for a machine instruction offset.
`ArrayList<CallSite>`	`getNonInlinedCallSites()`
`boolean`	`hasInlinedEdge(RVMMethod caller, int bcIndex, RVMMethod callee)` This method searches the machine code maps and determines if the given call edge is definitely inlined into the method.
`private boolean`	`isBigEntry(int entry)`
`private boolean`	`isHugeEntry(int entry)`
`private int`	`nextEntry(int entry)`
`int`	`nextLocation(int currentIndex)`
`private void`	`printMCInformationEntry(int entry, boolean DUMP_MAPS)`
`private void`	`recordStats(RVMMethod method, int mapSize, int machineCodeSize, boolean DUMP_MAP_SIZES)`
`boolean`	`registerIsSet(int entry, int registerNumber)`
`(package private) int`	`size()`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - START_OF_ENTRY
```
private static final int START_OF_ENTRY
```
    See Also:
    
    Constant Field Values
  - START_OF_BIG_ENTRY
```
private static final int START_OF_BIG_ENTRY
```
    See Also:
    
    Constant Field Values
  - START_OF_HUGE_ENTRY
```
private static final int START_OF_HUGE_ENTRY
```
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    Constant Field Values
  - START_BITS
```
private static final int START_BITS
```
    See Also:
    
    Constant Field Values
  - CALL_MASK
```
private static final int CALL_MASK
```
    See Also:
    
    Constant Field Values
  - CALL_SHIFT
```
private static final int CALL_SHIFT
```
    See Also:
    
    Constant Field Values
  - BCI_MASK
```
private static final int BCI_MASK
```
    See Also:
    
    Constant Field Values
  - BCI_SHIFT
```
private static final int BCI_SHIFT
```
    See Also:
    
    Constant Field Values
  - IEI_MASK
```
private static final int IEI_MASK
```
    See Also:
    
    Constant Field Values
  - IEI_SHIFT
```
private static final int IEI_SHIFT
```
    See Also:
    
    Constant Field Values
  - GCI_MASK
```
private static final int GCI_MASK
```
    See Also:
    
    Constant Field Values
  - GCI_SHIFT
```
private static final int GCI_SHIFT
```
    See Also:
    
    Constant Field Values
  - OFFSET_MASK
```
private static final int OFFSET_MASK
```
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    Constant Field Values
  - OFFSET_SHIFT
```
private static final int OFFSET_SHIFT
```
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    Constant Field Values
  - INVALID_GCI
```
private static final int INVALID_GCI
```
    See Also:
    
    Constant Field Values
  - INVALID_BCI
```
private static final int INVALID_BCI
```
    See Also:
    
    Constant Field Values
  - INVALID_IEI
```
private static final int INVALID_IEI
```
    See Also:
    
    Constant Field Values
  - SIZEOF_ENTRY
```
private static final int SIZEOF_ENTRY
```
    See Also:
    
    Constant Field Values
  - BIG_CALL_MASK
```
private static final int BIG_CALL_MASK
```
    See Also:
    
    Constant Field Values
  - BIG_CALL_SHIFT
```
private static final int BIG_CALL_SHIFT
```
    See Also:
    
    Constant Field Values
  - BIG_CALL_IDX_ADJ
```
private static final int BIG_CALL_IDX_ADJ
```
    See Also:
    
    Constant Field Values
  - BIG_BCI_MASK
```
private static final int BIG_BCI_MASK
```
    See Also:
    
    Constant Field Values
  - BIG_BCI_SHIFT
```
private static final int BIG_BCI_SHIFT
```
    See Also:
    
    Constant Field Values
  - BIG_BCI_IDX_ADJ
```
private static final int BIG_BCI_IDX_ADJ
```
    See Also:
    
    Constant Field Values
  - BIG_IEI_MASK
```
private static final int BIG_IEI_MASK
```
    See Also:
    
    Constant Field Values
  - BIG_IEI_SHIFT
```
private static final int BIG_IEI_SHIFT
```
    See Also:
    
    Constant Field Values
  - BIG_IEI_IDX_ADJ
```
private static final int BIG_IEI_IDX_ADJ
```
    See Also:
    
    Constant Field Values
  - BIG_GCI_MASK
```
private static final int BIG_GCI_MASK
```
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    Constant Field Values
  - BIG_GCI_SHIFT
```
private static final int BIG_GCI_SHIFT
```
    See Also:
    
    Constant Field Values
  - BIG_GCI_IDX_ADJ
```
private static final int BIG_GCI_IDX_ADJ
```
    See Also:
    
    Constant Field Values
  - BIG_OFFSET_MASK
```
private static final int BIG_OFFSET_MASK
```
    See Also:
    
    Constant Field Values
  - BIG_OFFSET_SHIFT
```
private static final int BIG_OFFSET_SHIFT
```
    See Also:
    
    Constant Field Values
  - BIG_OFFSET_IDX_ADJ
```
private static final int BIG_OFFSET_IDX_ADJ
```
    See Also:
    
    Constant Field Values
  - BIG_INVALID_GCI
```
private static final int BIG_INVALID_GCI
```
    See Also:
    
    Constant Field Values
  - BIG_INVALID_BCI
```
private static final int BIG_INVALID_BCI
```
    See Also:
    
    Constant Field Values
  - BIG_INVALID_IEI
```
private static final int BIG_INVALID_IEI
```
    See Also:
    
    Constant Field Values
  - SIZEOF_BIG_ENTRY
```
private static final int SIZEOF_BIG_ENTRY
```
    See Also:
    
    Constant Field Values
  - HUGE_CALL_MASK
```
private static final int HUGE_CALL_MASK
```
    See Also:
    
    Constant Field Values
  - HUGE_CALL_SHIFT
```
private static final int HUGE_CALL_SHIFT
```
    See Also:
    
    Constant Field Values
  - HUGE_CALL_IDX_ADJ
```
private static final int HUGE_CALL_IDX_ADJ
```
    See Also:
    
    Constant Field Values
  - HUGE_BCI_MASK
```
private static final int HUGE_BCI_MASK
```
    See Also:
    
    Constant Field Values
  - HUGE_BCI_SHIFT
```
private static final int HUGE_BCI_SHIFT
```
    See Also:
    
    Constant Field Values
  - HUGE_BCI_IDX_ADJ
```
private static final int HUGE_BCI_IDX_ADJ
```
    See Also:
    
    Constant Field Values
  - HUGE_IEI_MASK
```
private static final int HUGE_IEI_MASK
```
    See Also:
    
    Constant Field Values
  - HUGE_IEI_SHIFT
```
private static final int HUGE_IEI_SHIFT
```
    See Also:
    
    Constant Field Values
  - HUGE_IEI_IDX_ADJ
```
private static final int HUGE_IEI_IDX_ADJ
```
    See Also:
    
    Constant Field Values
  - HUGE_GCI_MASK
```
private static final int HUGE_GCI_MASK
```
    See Also:
    
    Constant Field Values
  - HUGE_GCI_SHIFT
```
private static final int HUGE_GCI_SHIFT
```
    See Also:
    
    Constant Field Values
  - HUGE_GCI_IDX_ADJ
```
private static final int HUGE_GCI_IDX_ADJ
```
    See Also:
    
    Constant Field Values
  - HUGE_OFFSET_MASK
```
private static final int HUGE_OFFSET_MASK
```
    See Also:
    
    Constant Field Values
  - HUGE_OFFSET_SHIFT
```
private static final int HUGE_OFFSET_SHIFT
```
    See Also:
    
    Constant Field Values
  - HUGE_OFFSET_IDX_ADJ
```
private static final int HUGE_OFFSET_IDX_ADJ
```
    See Also:
    
    Constant Field Values
  - HUGE_INVALID_GCI
```
private static final int HUGE_INVALID_GCI
```
    See Also:
    
    Constant Field Values
  - HUGE_INVALID_BCI
```
private static final int HUGE_INVALID_BCI
```
    See Also:
    
    Constant Field Values
  - HUGE_INVALID_IEI
```
private static final int HUGE_INVALID_IEI
```
    See Also:
    
    Constant Field Values
  - SIZEOF_HUGE_ENTRY
```
private static final int SIZEOF_HUGE_ENTRY
```
    See Also:
    
    Constant Field Values
  - IS_UNGUARDED_CALL
```
private static final int IS_UNGUARDED_CALL
```
    See Also:
    
    Constant Field Values
  - IS_GUARDED_CALL
```
private static final int IS_GUARDED_CALL
```
    See Also:
    
    Constant Field Values
  - MCInformation
```
private final int[] MCInformation
```
    Hold entries as defined by the constants above.
  - gcMaps
```
private final int[] gcMaps
```
    array of GC maps as defined by OptGCMap
  - inlineEncoding
```
public final int[] inlineEncoding
```
    encoded data as defined by OptEncodedCallSiteTree.
  - totalMCSize
```
private static int totalMCSize
```
    Running totals for the size of machine code and maps
  - totalMapSize
```
private static int totalMapSize
```
  - emptyMachineCodeMap
```
private static final OptMachineCodeMap emptyMachineCodeMap
```
    A machine code map when no information is present
  - TYPE
```
private static final TypeReference TYPE
```
- Constructor Detail
  - OptMachineCodeMap
```
private OptMachineCodeMap(int[] _MCInformation,
                          int[] _gcMaps,
                          int[] _inlineEncoding)
```
- Method Detail
  - create
```
static OptMachineCodeMap create(IR ir,
                                int machineCodeSize)
```
    Creates the map, called during compilation
    
    Parameters:
    
    ir - the ir object for this method
    
    machineCodeSize - the number of machine code instructions generated.
    
    Returns:
    
    the created map
  - getBytecodeIndexForMCOffset
```
public int getBytecodeIndexForMCOffset(Offset MCOffset)
```
    Get the bytecode index for a machine instruction offset.
    
    Parameters:
    
    MCOffset - the machine code offset of interest
    
    Returns:
    
    -1 if unknown.
  - getMethodForMCOffset
```
public NormalMethod getMethodForMCOffset(Offset MCOffset)
```
    Get the RVMMethod for a machine instruction offset. This method is the source method that the instruction came from.
    
    Parameters:
    
    MCOffset - the machine code offset of interest
    
    Returns:
    
    null if unknown
  - getInlineEncodingForMCOffset
```
public int getInlineEncodingForMCOffset(Offset MCOffset)
```
    Return the inlining encoding index for the machine instruction offset.
    
    Parameters:
    
    MCOffset - the machine code offset of interest
    
    Returns:
    
    -1 if unknown.
  - findGCMapIndex
```
public int findGCMapIndex(Offset MCOffset)
```
    This method searches for the GC map corresponding to the passed machine code offset. If no map is present, an error has occurred and OptGCMap.ERROR is returned.
    
    Parameters:
    
    MCOffset - the machine code offset to look for
    
    Returns:
    
    the GC map index or OptGCMap.ERROR
  - getNonInlinedCallSites
```
public ArrayList<CallSite> getNonInlinedCallSites()
```
    Returns:
    
    an arraylist of CallSite objects representing all non-inlined callsites in the method. Returns null if there are no such callsites.
  - hasInlinedEdge
```
public boolean hasInlinedEdge(RVMMethod caller,
                              int bcIndex,
                              RVMMethod callee)
```
    This method searches the machine code maps and determines if the given call edge is definitely inlined into the method. NOTE: This current implementation may return false even if the edge actually was inlined. This happens when no GC point occurs within the inlined body. This is less than ideal; we need to fix this at some point.
    
    Parameters:
    
    caller - caller RVMMethod
    
    bcIndex - bytecode index of the caller method
    
    callee - callee RVMMethod
    
    Returns:
    
    true if the call edge is definitely inlined in this compiled method.
  - gcMapInformation
```
public int gcMapInformation(int index)
```
  - registerIsSet
```
public boolean registerIsSet(int entry,
                             int registerNumber)
```
  - nextLocation
```
public int nextLocation(int currentIndex)
```
    Parameters:
    
    currentIndex - index for current location
    
    Returns:
    
    the next (relative) location or -1 for no more locations
  - findMCEntry
```
private int findMCEntry(Offset MCOffset)
```
    Does a binary search of the machine code maps to find the index in MCInformation where the entry for the argument machine code offset starts. Will return -1 if the entry doesn't exist.
    
    Parameters:
    
    MCOffset - the machine code offset of interest
    
    Returns:
    
    -1 if no entry exists, the index of the matching entry otherwise
  - nextEntry
```
private int nextEntry(int entry)
```
  - generateMCInformation
```
private static OptMachineCodeMap generateMCInformation(GCIRMap irMap,
                                                       boolean DUMP_MAPS,
                                                       MachineCodeOffsets mcOffsets)
```
    This method walks the IR map, and for each entry it creates the machine code mapping information for the entry. It is called during the compilation of the method, not at GC time.
    
    Parameters:
    
    irMap - the irmap to translate from
    
    DUMP_MAPS - dump while we work
    
    mcOffsets - machine code offset information
    
    Returns:
    
    the machine code map
  - ensureCorrectMapConstruction
```
private static void ensureCorrectMapConstruction(MachineCodeOffsets mcOffsets,
                                                 Instruction instr)
```
    Ensures correct map construction by either correcting oddities or failing immediately in case of errors.
    
    Parameters:
    
    mcOffsets - machine code offset information
    
    instr - the instruction to be processed
  - getMCOffset
```
private int getMCOffset(int entry)
```
    Returns the MCOffset for the entry passed
    
    Parameters:
    
    entry - the index of the start of the entry
    
    Returns:
    
    the MCOffset for this entry
  - getGCMapIndex
```
private int getGCMapIndex(int entry)
```
    Returns the GC map index for the entry passed
    
    Parameters:
    
    entry - the index of the start of the entry
    
    Returns:
    
    the GC map entry index for this entry (or -1 if none)
  - getBytecodeIndex
```
private int getBytecodeIndex(int entry)
```
    Returns the Bytecode index for the entry passed
    
    Parameters:
    
    entry - the index of the start of the entry
    
    Returns:
    
    the bytecode index for this entry (-1 if unknown)
  - getInlineEncodingIndex
```
private int getInlineEncodingIndex(int entry)
```
    Returns the inline encoding index for the entry passed.
    
    Parameters:
    
    entry - the index of the start of the entry
    
    Returns:
    
    the inline encoding index for this entry (-1 if unknown)
  - getCallInfo
```
private int getCallInfo(int entry)
```
    Returns the call info for the entry passed.
    
    Parameters:
    
    entry - the index of the start of the entry
    
    Returns:
    
    the call info for this entry
  - isBigEntry
```
private boolean isBigEntry(int entry)
```
    Parameters:
    
    entry - the entry's index
    
    Returns:
    
    whether the the entry is a big entry
  - isHugeEntry
```
private boolean isHugeEntry(int entry)
```
    Parameters:
    
    entry - the entry's index
    
    Returns:
    
    whether the the entry is a huge entry
  - dumpMCInformation
```
public void dumpMCInformation(boolean DUMP_MAPS)
```
  - printMCInformationEntry
```
private void printMCInformationEntry(int entry,
                                     boolean DUMP_MAPS)
```
  - recordStats
```
private void recordStats(RVMMethod method,
                         int mapSize,
                         int machineCodeSize,
                         boolean DUMP_MAP_SIZES)
```
  - size
```
int size()
```
    Returns:
    
    total bytes of machine code maps

Class OptMachineCodeMap

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

START_OF_ENTRY

START_OF_BIG_ENTRY

START_OF_HUGE_ENTRY

START_BITS

CALL_MASK

CALL_SHIFT

BCI_MASK

BCI_SHIFT

IEI_MASK

IEI_SHIFT

GCI_MASK

GCI_SHIFT

OFFSET_MASK

OFFSET_SHIFT

INVALID_GCI

INVALID_BCI

INVALID_IEI

SIZEOF_ENTRY

BIG_CALL_MASK

BIG_CALL_SHIFT

BIG_CALL_IDX_ADJ

BIG_BCI_MASK

BIG_BCI_SHIFT

BIG_BCI_IDX_ADJ

BIG_IEI_MASK

BIG_IEI_SHIFT

BIG_IEI_IDX_ADJ

BIG_GCI_MASK

BIG_GCI_SHIFT

BIG_GCI_IDX_ADJ

BIG_OFFSET_MASK

BIG_OFFSET_SHIFT

BIG_OFFSET_IDX_ADJ

BIG_INVALID_GCI

BIG_INVALID_BCI

BIG_INVALID_IEI

SIZEOF_BIG_ENTRY

HUGE_CALL_MASK

HUGE_CALL_SHIFT

HUGE_CALL_IDX_ADJ

HUGE_BCI_MASK

HUGE_BCI_SHIFT

HUGE_BCI_IDX_ADJ

HUGE_IEI_MASK

HUGE_IEI_SHIFT

HUGE_IEI_IDX_ADJ

HUGE_GCI_MASK

HUGE_GCI_SHIFT

HUGE_GCI_IDX_ADJ

HUGE_OFFSET_MASK

HUGE_OFFSET_SHIFT

HUGE_OFFSET_IDX_ADJ

HUGE_INVALID_GCI

HUGE_INVALID_BCI

HUGE_INVALID_IEI

SIZEOF_HUGE_ENTRY

IS_UNGUARDED_CALL

IS_GUARDED_CALL

MCInformation

gcMaps

inlineEncoding

totalMCSize

totalMapSize

emptyMachineCodeMap

TYPE

Constructor Detail

OptMachineCodeMap

Method Detail

create

getBytecodeIndexForMCOffset

getMethodForMCOffset

getInlineEncodingForMCOffset

findGCMapIndex

getNonInlinedCallSites