jif.extension
Class CallHelper

java.lang.Object
  jif.extension.CallHelper

public class CallHelper
extends java.lang.Object

This is a tool to label check method calls. This class should be used by creating an instance of it, and then calling the method checkCall(LabelChecker). After the call to that method, the remaining methods (which are getter methods) may be called.

Field Summary

protected java.util.List	actualArgLabels Labels of the actual arguments.
protected java.util.List	actualArgs Copy of the list of the Expr s that are the arguments to the procedure call.
protected java.util.List	actualParamLabels Labels of the actual parameters.
protected boolean	callChecked
protected polyglot.types.ReferenceType	calleeContainer
protected boolean	overrideChecker
protected JifProcedureInstance	pi The procedure being called.
protected polyglot.util.Position	position The position of the procedure call
protected polyglot.ast.Expr	receiverExpr
protected Label	receiverLabel Label of the reference to the object on which the procedure is being called.
protected polyglot.types.Type	returnType The return type of the procedure, if there is one.
protected PathMap	X The PathMap for the procedure call.

Constructor Summary

	CallHelper(Label receiverLabel, polyglot.ast.Receiver receiver, polyglot.types.ReferenceType calleeContainer, JifProcedureInstance pi, java.util.List actualArgs, polyglot.util.Position position)
protected	CallHelper(Label receiverLabel, polyglot.ast.Receiver receiver, polyglot.types.ReferenceType calleeContainer, JifProcedureInstance pi, java.util.List actualArgs, polyglot.util.Position position, boolean overrideChecker)

Method Summary

void	bindVarLabels(LabelChecker lc, VarLabel receiverVarLabel, java.util.List actualArgVarLabels, java.util.List actualParamVarLabels) Bind the given var labels to the appropriate labels that have been calculated during the call checking.
void	checkCall(LabelChecker lc, java.util.List throwTypes, boolean targetMayBeNull) Check method calls.
void	checkOverride(LabelChecker lc) this.pi is a Jif method instance that this.overridingMethod is attempting to override.
protected void	constrainArg(LabelChecker lc, int index, polyglot.ast.Expr Ej, polyglot.types.Type formalType) Add constraints to ensure that the labels of the actual arguments are less than the upper bounds of the formal arguments.
protected void	constrainFinalActualArgs(JifTypeSystem jts) Make sure that the actual arg for any formal arg that appears in the signature is final.
protected PathMap	excPathMap(LabelChecker lc, Label returnLabel, Label pcPriorToInvoke, java.util.List throwTypes)
protected static java.util.List	getArgLabelsFromFormalTypes(java.util.List formalTypes, JifTypeSystem jts, polyglot.util.Position pos)
Label	instantiate(JifContext A, Label L)
Principal	instantiate(JifContext A, Principal p) replaces any signature ArgLabels in p with the appropriate label, and replaces any signature ArgPrincipal with the appropriate prinicipal.
polyglot.types.Type	instantiate(JifContext A, polyglot.types.Type t)
protected PathMap	labelCheckAndConstrainArgs(LabelChecker lc, PathMap Xjoin) Label check the arguments.
protected PathMap	labelCheckAndConstrainParams(LabelChecker lc, java.util.List throwTypes)
java.util.List	labelCheckedArgs()
static CallHelper	OverrideHelper(JifMethodInstance overridden, JifMethodInstance overriding, LabelChecker lc)
protected static void	report(int obscurity, java.lang.String s)
protected Label	resolvePCBound(LabelChecker lc)
protected Label	resolveReturnLabel(LabelChecker lc) Returns the instantiated return label.
protected Label	resolveReturnValueLabel(LabelChecker lc, Label returnLabel) Returns the instantiated return value label joined with returnLabel.
polyglot.types.Type	returnType()
protected void	satisfiesConstraints(JifProcedureInstance jpi, LabelChecker lc) Check if the caller has sufficient authority, and label constraints are satisfied Thesis, Figure 4.29
protected static boolean	shouldReport(int obscurity)
PathMap	X()

Methods inherited from class java.lang.Object

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

Field Detail

receiverLabel

protected final Label receiverLabel

Label of the reference to the object on which the procedure is being called.

receiverExpr

protected final polyglot.ast.Expr receiverExpr

calleeContainer

protected final polyglot.types.ReferenceType calleeContainer

actualArgs

protected final java.util.List actualArgs

Copy of the list of the Expr s that are the arguments to the procedure call. As we label check the argument expressions, we replace the elements of this list with the label checked versions of the argument expressions.

pi

protected final JifProcedureInstance pi

The procedure being called. Also the MethodInstance of the overridden method, when this class is used for overriding checking.

position

protected final polyglot.util.Position position

The position of the procedure call

actualArgLabels

protected java.util.List actualArgLabels

Labels of the actual arguments.

actualParamLabels

protected java.util.List actualParamLabels

Labels of the actual parameters.

X

protected PathMap X

The PathMap for the procedure call.

returnType

protected polyglot.types.Type returnType

The return type of the procedure, if there is one.

callChecked

protected boolean callChecked

overrideChecker

protected final boolean overrideChecker

Constructor Detail

CallHelper

public CallHelper(Label receiverLabel,
                  polyglot.ast.Receiver receiver,
                  polyglot.types.ReferenceType calleeContainer,
                  JifProcedureInstance pi,
                  java.util.List actualArgs,
                  polyglot.util.Position position)

CallHelper

protected CallHelper(Label receiverLabel,
                     polyglot.ast.Receiver receiver,
                     polyglot.types.ReferenceType calleeContainer,
                     JifProcedureInstance pi,
                     java.util.List actualArgs,
                     polyglot.util.Position position,
                     boolean overrideChecker)

Method Detail

shouldReport

protected static boolean shouldReport(int obscurity)

report

protected static void report(int obscurity,
                             java.lang.String s)

OverrideHelper

public static CallHelper OverrideHelper(JifMethodInstance overridden,
                                        JifMethodInstance overriding,
                                        LabelChecker lc)

returnType

public polyglot.types.Type returnType()

labelCheckedArgs

public java.util.List labelCheckedArgs()

X

public PathMap X()

labelCheckAndConstrainParams

protected PathMap labelCheckAndConstrainParams(LabelChecker lc,
                                               java.util.List throwTypes)
                                        throws polyglot.types.SemanticException

Throws:

polyglot.types.SemanticException

labelCheckAndConstrainArgs

protected PathMap labelCheckAndConstrainArgs(LabelChecker lc,
                                             PathMap Xjoin)
                                      throws polyglot.types.SemanticException

Label check the arguments. Also initializes the array argLabels, that is the labels of the actual arguments.

Parameters:

Xjoin - The pathmap for the call so far, that is, up to the point just before the evaluation of the actual arguments.

Returns:

The PathMap for the evaluation of all actual arguments, that is, join_j xj, for all actual arguments xj.

Throws:

polyglot.types.SemanticException

constrainArg

protected void constrainArg(LabelChecker lc,
                            int index,
                            polyglot.ast.Expr Ej,
                            polyglot.types.Type formalType)
                     throws polyglot.types.SemanticException

Add constraints to ensure that the labels of the actual arguments are less than the upper bounds of the formal arguments.

Parameters:

index - the ith arg

Ej - the expression of the ith actual arg

formalType - the type of ith formal arg.

Throws:

polyglot.types.SemanticException

constrainFinalActualArgs

protected void constrainFinalActualArgs(JifTypeSystem jts)
                                 throws polyglot.types.SemanticException

Make sure that the actual arg for any formal arg that appears in the signature is final.

Throws:

polyglot.types.SemanticException

resolvePCBound

protected Label resolvePCBound(LabelChecker lc)
                        throws polyglot.types.SemanticException

Throws:

polyglot.types.SemanticException

resolveReturnLabel

protected Label resolveReturnLabel(LabelChecker lc)
                            throws polyglot.types.SemanticException

Returns the instantiated return label.

Throws:

polyglot.types.SemanticException

resolveReturnValueLabel

protected Label resolveReturnValueLabel(LabelChecker lc,
                                        Label returnLabel)
                                 throws polyglot.types.SemanticException

Returns the instantiated return value label joined with returnLabel.

Throws:

polyglot.types.SemanticException

excPathMap

protected PathMap excPathMap(LabelChecker lc,
                             Label returnLabel,
                             Label pcPriorToInvoke,
                             java.util.List throwTypes)
                      throws polyglot.types.SemanticException

Throws:

polyglot.types.SemanticException

checkCall

public void checkCall(LabelChecker lc,
                      java.util.List throwTypes,
                      boolean targetMayBeNull)
               throws polyglot.types.SemanticException

Check method calls. (Thesis, Figure 4.29)

Throws:

polyglot.types.SemanticException

satisfiesConstraints

protected void satisfiesConstraints(JifProcedureInstance jpi,
                                    LabelChecker lc)
                             throws polyglot.types.SemanticException

Check if the caller has sufficient authority, and label constraints are satisfied Thesis, Figure 4.29

Throws:

polyglot.types.SemanticException

bindVarLabels

public void bindVarLabels(LabelChecker lc,
                          VarLabel receiverVarLabel,
                          java.util.List actualArgVarLabels,
                          java.util.List actualParamVarLabels)
                   throws polyglot.types.SemanticException

Bind the given var labels to the appropriate labels that have been calculated during the call checking.

Parameters:

lc - the LabelChecker

receiverVarLabel - the VarLabel used to stand in for the label of the receiver

actualArgVarLabels - a list of VarLabels that were used to stand in for the labels of the actual arguments

actualParamVarLabels - a list of VarLabels that were used to stand in for the labels of the actual parameters

Throws:

polyglot.types.SemanticException

getArgLabelsFromFormalTypes

protected static java.util.List getArgLabelsFromFormalTypes(java.util.List formalTypes,
                                                            JifTypeSystem jts,
                                                            polyglot.util.Position pos)
                                                     throws polyglot.types.SemanticException

Throws:

polyglot.types.SemanticException

instantiate

public Label instantiate(JifContext A,
                         Label L)
                  throws polyglot.types.SemanticException

Throws:

polyglot.types.SemanticException

instantiate

public Principal instantiate(JifContext A,
                             Principal p)
                      throws polyglot.types.SemanticException

replaces any signature ArgLabels in p with the appropriate label, and replaces any signature ArgPrincipal with the appropriate prinicipal.

Throws:

polyglot.types.SemanticException

instantiate

public polyglot.types.Type instantiate(JifContext A,
                                       polyglot.types.Type t)
                                throws polyglot.types.SemanticException

Throws:

polyglot.types.SemanticException

checkOverride

public void checkOverride(LabelChecker lc)
                   throws polyglot.types.SemanticException

this.pi is a Jif method instance that this.overridingMethod is attempting to override. Previous type checks have made sure that things like abstractness, access flags, throw sets, etc. are ok. We need to check that the labels conform.

Throws:

polyglot.types.SemanticException