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package com.ibm.wala.demandpa.flowgraph;
import java.util.List;
import java.util.Set;
import com.ibm.wala.classLoader.ArrayClass;
import com.ibm.wala.classLoader.IClass;
import com.ibm.wala.classLoader.IField;
import com.ibm.wala.classLoader.ProgramCounter;
import com.ibm.wala.demandpa.util.ArrayContents;
import com.ibm.wala.demandpa.util.MemoryAccessMap;
import com.ibm.wala.ipa.callgraph.CGNode;
import com.ibm.wala.ipa.callgraph.CallGraph;
import com.ibm.wala.ipa.callgraph.propagation.FilteredPointerKey;
import com.ibm.wala.ipa.callgraph.propagation.HeapModel;
import com.ibm.wala.ipa.callgraph.propagation.InstanceKey;
import com.ibm.wala.ipa.callgraph.propagation.PointerKey;
import com.ibm.wala.ipa.callgraph.propagation.SSAPropagationCallGraphBuilder;
import com.ibm.wala.ipa.cha.ClassHierarchy;
import com.ibm.wala.ssa.IR;
import com.ibm.wala.ssa.ISSABasicBlock;
import com.ibm.wala.ssa.SSAAbstractInvokeInstruction;
import com.ibm.wala.ssa.SSAArrayLengthInstruction;
import com.ibm.wala.ssa.SSAArrayLoadInstruction;
import com.ibm.wala.ssa.SSAArrayStoreInstruction;
import com.ibm.wala.ssa.SSABinaryOpInstruction;
import com.ibm.wala.ssa.SSACheckCastInstruction;
import com.ibm.wala.ssa.SSAComparisonInstruction;
import com.ibm.wala.ssa.SSAConversionInstruction;
import com.ibm.wala.ssa.SSAGetCaughtExceptionInstruction;
import com.ibm.wala.ssa.SSAGetInstruction;
import com.ibm.wala.ssa.SSAInstanceofInstruction;
import com.ibm.wala.ssa.SSAInstruction;
import com.ibm.wala.ssa.SSAInstruction.Visitor;
import com.ibm.wala.ssa.SSAInvokeInstruction;
import com.ibm.wala.ssa.SSALoadMetadataInstruction;
import com.ibm.wala.ssa.SSANewInstruction;
import com.ibm.wala.ssa.SSAPiInstruction;
import com.ibm.wala.ssa.SSAPutInstruction;
import com.ibm.wala.ssa.SSAReturnInstruction;
import com.ibm.wala.ssa.SSAThrowInstruction;
import com.ibm.wala.ssa.SSAUnaryOpInstruction;
import com.ibm.wala.ssa.SymbolTable;
import com.ibm.wala.types.FieldReference;
import com.ibm.wala.types.TypeReference;
import com.ibm.wala.util.collections.HashSetFactory;
import com.ibm.wala.util.collections.MapUtil;
import com.ibm.wala.util.debug.Assertions;
/**
* A flow graph including both pointer and primitive values.
*
* TODO share more code with {@link DemandPointerFlowGraph}
*
* @author Manu Sridharan
*
*/
public class DemandValueFlowGraph extends AbstractDemandFlowGraph {
public DemandValueFlowGraph(CallGraph cg, HeapModel heapModel, MemoryAccessMap mam, ClassHierarchy cha) {
super(cg, heapModel, mam, cha);
}
@Override
protected void addNodesForParameters(CGNode node, IR ir) {
SymbolTable symbolTable = ir.getSymbolTable();
int numParams = symbolTable.getNumberOfParameters();
for (int i = 0; i < numParams; i++) {
int parameter = symbolTable.getParameter(i);
PointerKey paramPk = heapModel.getPointerKeyForLocal(node, parameter);
addNode(paramPk);
params.put(paramPk, node);
}
PointerKey returnKey = heapModel.getPointerKeyForReturnValue(node);
addNode(returnKey);
returns.put(returnKey, node);
PointerKey exceptionReturnKey = heapModel.getPointerKeyForExceptionalReturnValue(node);
addNode(exceptionReturnKey);
returns.put(exceptionReturnKey, node);
}
@Override
protected FlowStatementVisitor makeVisitor(CGNode node) {
return new AllValsStatementVisitor(node);
}
private class AllValsStatementVisitor extends Visitor implements FlowStatementVisitor {
/**
* The node whose statements we are currently traversing
*/
protected final CGNode node;
/**
* The governing IR
*/
protected final IR ir;
/**
* The basic block currently being processed
*/
private ISSABasicBlock basicBlock;
/**
* Governing symbol table
*/
protected final SymbolTable symbolTable;
public AllValsStatementVisitor(CGNode node) {
this.node = node;
this.ir = node.getIR();
this.symbolTable = ir.getSymbolTable();
assert symbolTable != null;
}
/*
* @see com.ibm.domo.ssa.SSAInstruction.Visitor#visitArrayLoad(com.ibm.domo.ssa.SSAArrayLoadInstruction)
*/
@Override
public void visitArrayLoad(SSAArrayLoadInstruction instruction) {
PointerKey result = heapModel.getPointerKeyForLocal(node, instruction.getDef());
PointerKey arrayRef = heapModel.getPointerKeyForLocal(node, instruction.getArrayRef());
// TODO optimizations for purely local stuff
addNode(result);
addNode(arrayRef);
addEdge(result, arrayRef, GetFieldLabel.make(ArrayContents.v()));
}
/*
* @see com.ibm.domo.ssa.SSAInstruction.Visitor#visitArrayStore(com.ibm.domo.ssa.SSAArrayStoreInstruction)
*/
@Override
public void visitArrayStore(SSAArrayStoreInstruction instruction) {
// make node for used value
PointerKey value = heapModel.getPointerKeyForLocal(node, instruction.getValue());
PointerKey arrayRef = heapModel.getPointerKeyForLocal(node, instruction.getArrayRef());
// TODO purely local optimizations
addNode(value);
addNode(arrayRef);
addEdge(arrayRef, value, PutFieldLabel.make(ArrayContents.v()));
}
/*
* @see com.ibm.domo.ssa.SSAInstruction.Visitor#visitCheckCast(com.ibm.domo.ssa.SSACheckCastInstruction)
*/
@Override
public void visitCheckCast(SSACheckCastInstruction instruction) {
Set<IClass> types = HashSetFactory.make();
for(TypeReference t : instruction.getDeclaredResultTypes()) {
IClass cls = cha.lookupClass(t);
if (cls == null) {
return;
} else {
types.add(cls);
}
}
PointerKey result = heapModel.getFilteredPointerKeyForLocal(node,
instruction.getResult(),
new FilteredPointerKey.MultipleClassesFilter(types.toArray(new IClass[ types.size() ])) );
PointerKey value = heapModel.getPointerKeyForLocal(node, instruction.getVal());
addNode(result);
addNode(value);
addEdge(result, value, AssignLabel.noFilter());
}
/*
* @see com.ibm.domo.ssa.SSAInstruction.Visitor#visitReturn(com.ibm.domo.ssa.SSAReturnInstruction)
*/
@Override
public void visitReturn(SSAReturnInstruction instruction) {
// skip returns of primitive type
if (instruction.returnsVoid()) {
return;
} else {
// just make a node for the def'd value
PointerKey def = heapModel.getPointerKeyForLocal(node, instruction.getResult());
addNode(def);
PointerKey returnValue = heapModel.getPointerKeyForReturnValue(node);
addNode(returnValue);
addEdge(returnValue, def, AssignLabel.noFilter());
}
}
/*
* @see com.ibm.domo.ssa.SSAInstruction.Visitor#visitGet(com.ibm.domo.ssa.SSAGetInstruction)
*/
@Override
public void visitGet(SSAGetInstruction instruction) {
visitGetInternal(instruction.getDef(), instruction.getRef(), instruction.isStatic(), instruction.getDeclaredField());
}
protected void visitGetInternal(int lval, int ref, boolean isStatic, FieldReference field) {
IField f = cg.getClassHierarchy().resolveField(field);
if (f == null) {
return;
}
PointerKey def = heapModel.getPointerKeyForLocal(node, lval);
assert def != null;
if (isStatic) {
PointerKey fKey = heapModel.getPointerKeyForStaticField(f);
addNode(def);
addNode(fKey);
// TODO assign global edge for context-sensitive
addEdge(def, fKey, AssignGlobalLabel.v());
} else {
PointerKey refKey = heapModel.getPointerKeyForLocal(node, ref);
addNode(def);
addNode(refKey);
// TODO purely local optimizations
addEdge(def, refKey, GetFieldLabel.make(f));
}
}
/*
* @see com.ibm.domo.ssa.Instruction.Visitor#visitPut(com.ibm.domo.ssa.PutInstruction)
*/
@Override
public void visitPut(SSAPutInstruction instruction) {
visitPutInternal(instruction.getVal(), instruction.getRef(), instruction.isStatic(), instruction.getDeclaredField());
}
public void visitPutInternal(int rval, int ref, boolean isStatic, FieldReference field) {
IField f = cg.getClassHierarchy().resolveField(field);
if (f == null) {
return;
}
PointerKey use = heapModel.getPointerKeyForLocal(node, rval);
assert use != null;
if (isStatic) {
PointerKey fKey = heapModel.getPointerKeyForStaticField(f);
addNode(use);
addNode(fKey);
// TODO assign global edge
addEdge(fKey, use, AssignGlobalLabel.v());
} else {
PointerKey refKey = heapModel.getPointerKeyForLocal(node, ref);
addNode(use);
addNode(refKey);
addEdge(refKey, use, PutFieldLabel.make(f));
}
}
/*
* @see com.ibm.domo.ssa.Instruction.Visitor#visitInvoke(com.ibm.domo.ssa.InvokeInstruction)
*/
@Override
public void visitInvoke(SSAInvokeInstruction instruction) {
for (int i = 0; i < instruction.getNumberOfUses(); i++) {
// just make nodes for parameters; we'll get to them when
// traversing
// from the callee
PointerKey use = heapModel.getPointerKeyForLocal(node, instruction.getUse(i));
addNode(use);
Set<SSAAbstractInvokeInstruction> s = MapUtil.findOrCreateSet(callParams, use);
s.add(instruction);
}
// for any def'd values, keep track of the fact that they are def'd
// by a call
if (instruction.hasDef()) {
PointerKey def = heapModel.getPointerKeyForLocal(node, instruction.getDef());
addNode(def);
callDefs.put(def, instruction);
}
PointerKey exc = heapModel.getPointerKeyForLocal(node, instruction.getException());
addNode(exc);
callDefs.put(exc, instruction);
}
/*
* @see com.ibm.domo.ssa.Instruction.Visitor#visitNew(com.ibm.domo.ssa.NewInstruction)
*/
@Override
public void visitNew(SSANewInstruction instruction) {
InstanceKey iKey = heapModel.getInstanceKeyForAllocation(node, instruction.getNewSite());
if (iKey == null) {
// something went wrong. I hope someone raised a warning.
return;
}
PointerKey def = heapModel.getPointerKeyForLocal(node, instruction.getDef());
addNode(iKey);
addNode(def);
addEdge(def, iKey, NewLabel.v());
IClass klass = iKey.getConcreteType();
int dim = 0;
InstanceKey lastInstance = iKey;
PointerKey lastVar = def;
while (klass != null && klass.isArrayClass()) {
klass = ((ArrayClass) klass).getElementClass();
// klass == null means it's a primitive
if (klass != null && klass.isArrayClass()) {
InstanceKey ik = heapModel.getInstanceKeyForMultiNewArray(node, instruction.getNewSite(), dim);
PointerKey pk = heapModel.getPointerKeyForArrayContents(lastInstance);
addNode(ik);
addNode(pk);
addEdge(pk, ik, NewLabel.v());
addEdge(lastVar, pk, PutFieldLabel.make(ArrayContents.v()));
lastInstance = ik;
lastVar = pk;
dim++;
}
}
}
/*
* (non-Javadoc)
*
* @see com.ibm.domo.ssa.Instruction.Visitor#visitThrow(com.ibm.domo.ssa.ThrowInstruction)
*/
@Override
public void visitThrow(SSAThrowInstruction instruction) {
// don't do anything: we handle exceptional edges
// in a separate pass
}
/*
* @see com.ibm.domo.ssa.Instruction.Visitor#visitGetCaughtException(com.ibm.domo.ssa.GetCaughtExceptionInstruction)
*/
@Override
public void visitGetCaughtException(SSAGetCaughtExceptionInstruction instruction) {
List<ProgramCounter> peis = SSAPropagationCallGraphBuilder.getIncomingPEIs(ir, getBasicBlock());
PointerKey def = heapModel.getPointerKeyForLocal(node, instruction.getDef());
Set<IClass> types = SSAPropagationCallGraphBuilder.getCaughtExceptionTypes(instruction, ir);
addExceptionDefConstraints(ir, node, peis, def, types);
}
/*
* @see com.ibm.domo.ssa.SSAInstruction.Visitor#visitPi(com.ibm.domo.ssa.SSAPiInstruction)
*/
@Override
public void visitPi(SSAPiInstruction instruction) {
PointerKey src = heapModel.getPointerKeyForLocal(node, instruction.getDef());
PointerKey dst = heapModel.getPointerKeyForLocal(node, instruction.getVal());
addNode(src);
addNode(dst);
addEdge(src, dst, AssignLabel.noFilter());
}
private void handleNonHeapInstruction(SSAInstruction instruction) {
for (int i = 0; i < instruction.getNumberOfDefs(); i++) {
int def = instruction.getDef(i);
PointerKey defPk = heapModel.getPointerKeyForLocal(node, def);
addNode(defPk);
for (int j = 0; j < instruction.getNumberOfUses(); j++) {
int use = instruction.getUse(j);
PointerKey usePk = heapModel.getPointerKeyForLocal(node, use);
addNode(usePk);
addEdge(defPk, usePk, AssignLabel.noFilter());
}
}
}
@Override
public void visitArrayLength(SSAArrayLengthInstruction instruction) {
handleNonHeapInstruction(instruction);
}
@Override
public void visitBinaryOp(SSABinaryOpInstruction instruction) {
handleNonHeapInstruction(instruction);
}
@Override
public void visitComparison(SSAComparisonInstruction instruction) {
handleNonHeapInstruction(instruction);
}
@Override
public void visitConversion(SSAConversionInstruction instruction) {
handleNonHeapInstruction(instruction);
}
@Override
public void visitInstanceof(SSAInstanceofInstruction instruction) {
handleNonHeapInstruction(instruction);
}
@Override
public void visitUnaryOp(SSAUnaryOpInstruction instruction) {
handleNonHeapInstruction(instruction);
}
public ISSABasicBlock getBasicBlock() {
return basicBlock;
}
/**
* The calling loop must call this in each iteration!
*/
@Override
public void setBasicBlock(ISSABasicBlock block) {
basicBlock = block;
}
@Override
public void visitLoadMetadata(SSALoadMetadataInstruction instruction) {
Assertions.UNREACHABLE();
}
}
}