InOutAnalyzer
=============

.. java:package:: fr.inria.tapenade.analysis
   :noindex:

.. java:type:: public final class InOutAnalyzer extends DataFlowAnalyzer

   In-out analysis (aka read-write).

Fields
------
CONSTANT
^^^^^^^^

.. java:field:: public static final int CONSTANT
   :outertype: InOutAnalyzer

   Constant that codes for the CONSTANT sub phase.

INOUT
^^^^^

.. java:field:: public static final int INOUT
   :outertype: InOutAnalyzer

   Constant that codes for the INOUT phase.

OTHER
^^^^^

.. java:field:: public static final int OTHER
   :outertype: InOutAnalyzer

   Constant for the three other phases.

UNUSED
^^^^^^

.. java:field:: public static final int UNUSED
   :outertype: InOutAnalyzer

   Constant that codes for the UNUSED sub phase.

USED_UNDEF
^^^^^^^^^^

.. java:field:: public static final int USED_UNDEF
   :outertype: InOutAnalyzer

   Constant that codes for the USED_UNDEF sub phase.

Methods
-------
analyze
^^^^^^^

.. java:method:: @Override protected boolean analyze()
   :outertype: InOutAnalyzer

   Runs in-out analysis on "curUnit", plus related analyses.

   :return: true if the analysis result for this curUnit has changed since the previous time.

compareChannelZoneDataDownstream
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. java:method:: @Override protected boolean compareChannelZoneDataDownstream(int mpZone, Block refBlock)
   :outertype: InOutAnalyzer

compareChannelZoneDataUpstream
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. java:method:: @Override protected boolean compareChannelZoneDataUpstream(int mpZone, Block refBlock)
   :outertype: InOutAnalyzer

compareDownstreamValues
^^^^^^^^^^^^^^^^^^^^^^^

.. java:method:: @Override protected boolean compareDownstreamValues()
   :outertype: InOutAnalyzer

   Compares the downstream info with the result of previous sweep. Sometimes (e.g. for INOUT) we think comparison might take too long, so we don't compare and we return the default "true".

compareUpstreamValues
^^^^^^^^^^^^^^^^^^^^^

.. java:method:: @Override protected boolean compareUpstreamValues()
   :outertype: InOutAnalyzer

   Compares the in-out data flow information with the same info of the previous sweep. Overwrites the previous info if different. @return true when the new result is different from the previous one, thus asking for a new FG sweep.

cumulCycleValueWithAdditional
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. java:method:: @Override protected void cumulCycleValueWithAdditional(SymbolTable commonSymbolTable)
   :outertype: InOutAnalyzer

   First initialize the cumul cycle-values if they are null, then accumulate the additional value into the cumul cycle-value.

cumulValueWithAdditional
^^^^^^^^^^^^^^^^^^^^^^^^

.. java:method:: @Override protected void cumulValueWithAdditional(SymbolTable commonSymbolTable)
   :outertype: InOutAnalyzer

   First initialize the cumul values if they are null, then accumulate the additional value into the cumul value.

getFrontierModifiedZones
^^^^^^^^^^^^^^^^^^^^^^^^

.. java:method:: public BoolVector getFrontierModifiedZones(TapList<FGArrow> frontier)
   :outertype: InOutAnalyzer

   When "frontier" is a list of converging flow arrows that define the entry into a fragment of the current Unit.

   :return: the vector of the zones that are modified by this fragment.

getFrontierPossiblyReadZones
^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. java:method:: public BoolVector getFrontierPossiblyReadZones(TapList<FGArrow> frontier)
   :outertype: InOutAnalyzer

   When "frontier" is a list of converging flow arrows that define the entry into a fragment of the current Unit.

   :return: the vector of the zones that are read/used by this fragment.

getFrontierPossiblyWrittenZones
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. java:method:: public BoolVector getFrontierPossiblyWrittenZones(TapList<FGArrow> frontier)
   :outertype: InOutAnalyzer

   When "frontier" is a list of converging flow arrows that define the entry into a fragment of the current Unit.

   :return: the vector of the zones that are possibly overwritten by this fragment.

getFrontierUnusedZones
^^^^^^^^^^^^^^^^^^^^^^

.. java:method:: public BoolVector getFrontierUnusedZones(TapList<FGArrow> frontier)
   :outertype: InOutAnalyzer

   When "frontier" is a list of converging flow arrows that define the entry into a fragment of the current Unit.

   :return: the vector of the zones that are unused by this fragment.

getIOeffectOfIOspec
^^^^^^^^^^^^^^^^^^^

.. java:method:: public static Tree getIOeffectOfIOspec(Tree ioSpec, int i, String ioOper, ToBool written, ToBool totally, SymbolTable symbolTable)
   :outertype: InOutAnalyzer

   For the IO specification element "ioSpec", which is at rank "i" in the list of IO specificators of an IO call to IO operation "ioOper".

   :return: the Tree of expressions that are affected for this ioSpec, and whether they are read or written, totally or not. VERY specific to FORTRAN (77?) IO syntax. cf VAX-Fortran manual.

getInOutOfRegion
^^^^^^^^^^^^^^^^

.. java:method:: public TapPair<BoolVector, BoolVector> getInOutOfRegion(TapTriplet<TapList<FGArrow>, TapList<Block>, TapList<FGArrow>> region, Unit unit)
   :outertype: InOutAnalyzer

   Run in-out analyzer locally on the piece of code defined by "region", and return the pair of the possibly read and oberwritten BoolVectors TODO: try use possiblyW info of the INOUT phase instead of MODIFIED of the CONSTANT phase.

getValueFlowingBack
^^^^^^^^^^^^^^^^^^^

.. java:method:: @Override protected boolean getValueFlowingBack()
   :outertype: InOutAnalyzer

getValueFlowingThrough
^^^^^^^^^^^^^^^^^^^^^^

.. java:method:: @Override protected boolean getValueFlowingThrough()
   :outertype: InOutAnalyzer

initializeCGForUnit
^^^^^^^^^^^^^^^^^^^

.. java:method:: @Override protected Object initializeCGForUnit()
   :outertype: InOutAnalyzer

   During initialization on the whole CallGraph, do whatever initialization is needed for "unit", i.e. set the results to null for normal units and to the default values for intrinsics, externals, etc...

initializeCumulValue
^^^^^^^^^^^^^^^^^^^^

.. java:method:: @Override protected void initializeCumulValue()
   :outertype: InOutAnalyzer

initializeFGForBlock
^^^^^^^^^^^^^^^^^^^^

.. java:method:: @Override protected void initializeFGForBlock()
   :outertype: InOutAnalyzer

   Initializes the in-out information through "curBlock".

initializeInitBlock
^^^^^^^^^^^^^^^^^^^

.. java:method:: @Override protected void initializeInitBlock()
   :outertype: InOutAnalyzer

   Set an identity information on the given initial block.

initializeUnit
^^^^^^^^^^^^^^

.. java:method:: @Override protected void initializeUnit()
   :outertype: InOutAnalyzer

   Initialize before one sweep on the curUnit.

isCheapDuplicableConstant
^^^^^^^^^^^^^^^^^^^^^^^^^

.. java:method:: public static boolean isCheapDuplicableConstant(Tree expression, Block block, Instruction instruction)
   :outertype: InOutAnalyzer

   :return: true when the "expression" is cheap and is not modified from the beginning of "block" till the end of the enclosing Unit.

propagateValuesBackwardThroughBlock
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. java:method:: @Override protected boolean propagateValuesBackwardThroughBlock()
   :outertype: InOutAnalyzer

propagateValuesForwardThroughBlock
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. java:method:: @Override protected boolean propagateValuesForwardThroughBlock()
   :outertype: InOutAnalyzer

   Only during USED_UNDEF phase, combine the "Initialized zones" info before "curBlock" with in-out infos through "curBlock", to obtain and store the "Initialized zones" after "curBlock".

run
^^^

.. java:method:: @Override protected void run(TapList<Unit> rootUnits)
   :outertype: InOutAnalyzer

   Runs in-out analysis, upwards from the leaves of the CallGraph. As a result, this function fills the inOut fields of each Unit.

runAnalysis
^^^^^^^^^^^

.. java:method:: public static void runAnalysis(CallGraph callGraph, TapList<Unit> rootUnits)
   :outertype: InOutAnalyzer

   Main trigger method. Runs In-Out analysis under the rootUnits. If the context for calling the differentiated root must be created, then pass rootUnits==null and the analysis will run on the complete CallGraph, including the parts that are not under the root differentiation Units.

setCurBlockEtc
^^^^^^^^^^^^^^

.. java:method:: @Override protected void setCurBlockEtc(Block block)
   :outertype: InOutAnalyzer

   Set curBlock, curSymbolTable, nDZ, nDRZ, vectorMap's.

   :param block: The new current Block.

setCurUnitEtc
^^^^^^^^^^^^^

.. java:method:: @Override public void setCurUnitEtc(Unit unit)
   :outertype: InOutAnalyzer

   Set the current unit "curUnit", and various other globals specific to curUnit.

   :param unit: The new current Unit.

setEmptyCumulAndCycleValues
^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. java:method:: @Override protected void setEmptyCumulAndCycleValues()
   :outertype: InOutAnalyzer

setExternalOrIntrinsicDefaultInOutInfo
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. java:method:: public static void setExternalOrIntrinsicDefaultInOutInfo(Unit unit)
   :outertype: InOutAnalyzer

   Computes the default in-out signature for an intrinsic, an external or a varFunction: All vars possibly read and possibly written, except for the function result, which is never read and completely written, and for the I-O streams and all system-predefined symbols, which are never read nor written. [llh: the following is arbitrary and may be discussed:] We also assume that variables in COMMON are not read nor writen, i.e. that the external routine does not touch the COMMON, even if it might see it.

setFgPhase
^^^^^^^^^^

.. java:method:: public void setFgPhase(int fgPhase)
   :outertype: InOutAnalyzer

   Set the current phase of the analysis at the flow graph level.

setFgSubPhase
^^^^^^^^^^^^^

.. java:method:: public void setFgSubPhase(int fgSubPhase)
   :outertype: InOutAnalyzer

   Set the current subphase of the analysis at the flow graph level, when fgPhase==OTHER.

terminateCGForUnit
^^^^^^^^^^^^^^^^^^

.. java:method:: @Override protected void terminateCGForUnit()
   :outertype: InOutAnalyzer

terminateUnit
^^^^^^^^^^^^^

.. java:method:: @Override protected boolean terminateUnit()
   :outertype: InOutAnalyzer

   Gets and stores the final InOut result on the "curUnit". The result is computed from the InOut value propagated back till the Entry Block. @return true when the result has changed since previous time.