+++ /dev/null
-package edu.berkeley.cs.megacz;
-
-import soot.*;
-import soot.util.*;
-import java.util.*;
-import soot.toolkits.scalar.*;
-import soot.jimple.*;
-import soot.toolkits.graph.*;
-import soot.*;
-import soot.jimple.*;
-import soot.toolkits.scalar.*;
-import soot.toolkits.graph.*;
-import soot.util.*;
-import java.util.*;
-
-/** Tracks which locals are definitely non-null.
- * Author: Patrick Lam (plam@sable.mcgill.ca)
- * Based on BranchedRefVarsAnalysis by Janus Godard (janus@place.org). */
-class JArena extends ForwardBranchedFlowAnalysis {
-
- protected Object newInitialFlow() { return fullSet.clone(); }
- protected Object entryInitialFlow() { return emptySet.clone(); }
- private void addGen(Unit u, Value v) { ArraySparseSet l = (ArraySparseSet)unitToGenerateSet.get(u); l.add(v); }
- private void addGensFor(DefinitionStmt u) {
- Value lo = u.getLeftOp();
- Value ro = u.getRightOp();
- if (ro instanceof NewExpr ||
- ro instanceof NewArrayExpr ||
- ro instanceof NewMultiArrayExpr ||
- ro instanceof ThisRef ||
- ro instanceof CaughtExceptionRef)
- addGen(u, lo);
- }
-
- protected void copy(Object src, Object dest) {
- FlowSet sourceSet = (FlowSet)src, destSet = (FlowSet) dest;
- sourceSet.copy(destSet);
- }
-
- protected void merge(Object src1, Object src2, Object dest) {
- FlowSet srcSet1 = (FlowSet) src1;
- FlowSet srcSet2 = (FlowSet) src2;
- FlowSet destSet = (FlowSet) dest;
- srcSet1.intersection(srcSet2, destSet);
- }
-
- FlowSet fullSet, emptySet;
- FlowUniverse allRefLocals;
- Map unitToGenerateSet;
-
- protected void flowThrough(Object srcValue, Unit unit, List fallOut, List branchOuts) {
- FlowSet dest;
- FlowSet src = (FlowSet) srcValue;
- Unit s = (Unit) unit;
-
- // Create working set.
- dest = (FlowSet)src.clone();
-
- // Take out kill set.
- Iterator boxIt = s.getDefBoxes().iterator();
- while (boxIt.hasNext()) {
- ValueBox box = (ValueBox) boxIt.next();
- Value value = box.getValue();
- if (value instanceof Local && value.getType() instanceof RefLikeType)
- dest.remove(value);
- }
-
- // Perform gen.
- dest.union((FlowSet)unitToGenerateSet.get(unit), dest);
-
- // Handle copy statements:
- // x = y && 'y' in src => add 'x' to dest
- if (s instanceof DefinitionStmt)
- {
- DefinitionStmt as = (DefinitionStmt) s;
-
- Value ro = as.getRightOp();
-
- // extract cast argument
- if (ro instanceof CastExpr) ro = ((CastExpr) ro).getOp();
-
- if (src.contains(ro) && as.getLeftOp() instanceof Local)
- dest.add(as.getLeftOp());
- }
-
- // Copy the out value to the fallthrough box (don't need iterator)
- {
- Iterator it = fallOut.iterator();
- while (it.hasNext()) {
- FlowSet fs = (FlowSet) (it.next());
- copy(dest, fs);
- }
- }
-
- // Copy the out value to all branch boxes.
- {
- Iterator it = branchOuts.iterator();
- while (it.hasNext()) {
- FlowSet fs = (FlowSet) (it.next());
- copy(dest, fs);
- }
- }
-
- // Handle if statements by patching dest sets.
- if (unit instanceof IfStmt)
- {
- Value cond = ((IfStmt)unit).getCondition();
- Value op1 = ((BinopExpr) cond).getOp1();
- Value op2 = ((BinopExpr) cond).getOp2();
- boolean isNeg = cond instanceof NeExpr;
- Value toGen = null;
-
- // case 1: opN is a local and opM is NullConstant
- // => opN nonnull on ne branch.
- if (op1 instanceof Local && op2 instanceof NullConstant)
- toGen = op1;
-
- if (op2 instanceof Local && op1 instanceof NullConstant)
- toGen = op2;
-
- if (toGen != null)
- {
- Iterator it = null;
-
- // if (toGen != null) goto l1: on branch, toGen nonnull.
- if (isNeg)
- it = branchOuts.iterator();
- else
- it = fallOut.iterator();
-
- while(it.hasNext()) {
- FlowSet fs = (FlowSet) (it.next());
- fs.add(toGen);
- }
- }
-
- // case 2: both ops are local and one op is non-null and testing equality
- if (op1 instanceof Local && op2 instanceof Local &&
- cond instanceof EqExpr)
- {
- toGen = null;
-
- if (src.contains(op1))
- toGen = op2;
- if (src.contains(op2))
- toGen = op1;
-
- if (toGen != null)
- {
- Iterator branchIt = branchOuts.iterator();
- while (branchIt.hasNext()) {
- FlowSet fs = (FlowSet) (branchIt.next());
- fs.add(toGen);
- }
- }
- }
- }
- }
-
- public JArena(UnitGraph g) {
- super(g);
-
- unitToGenerateSet = new HashMap();
-
- Body b = g.getBody();
-
- List refLocals = new LinkedList();
-
- // set up universe, empty, full sets.
-
- emptySet = new ArraySparseSet();
- fullSet = new ArraySparseSet();
-
- // Find all locals in body.
- Iterator localIt = b.getLocals().iterator();
- while (localIt.hasNext()) {
- Local l = (Local)localIt.next();
- if (l.getType() instanceof RefLikeType) fullSet.add(l);
- }
-
- // Create gen sets.
- Iterator unitIt = b.getUnits().iterator();
- while (unitIt.hasNext()) {
- Unit u = (Unit)unitIt.next();
- unitToGenerateSet.put(u, new ArraySparseSet());
-
- if (u instanceof DefinitionStmt) {
- Value lo = ((DefinitionStmt)u).getLeftOp();
- if (lo instanceof Local && lo.getType() instanceof RefLikeType)
- addGensFor((DefinitionStmt)u);
- }
-
- Iterator boxIt = u.getUseAndDefBoxes().iterator();
- while (boxIt.hasNext()) {
- Value boxValue = ((ValueBox) boxIt.next()).getValue();
- Value base = null;
-
- if(boxValue instanceof InstanceFieldRef) {
- base = ((InstanceFieldRef) (boxValue)).getBase();
- } else if (boxValue instanceof ArrayRef) {
- base = ((ArrayRef) (boxValue)).getBase();
- } else if (boxValue instanceof InstanceInvokeExpr) {
- base = ((InstanceInvokeExpr) boxValue).getBase();
- } else if (boxValue instanceof LengthExpr) {
- base = ((LengthExpr) boxValue).getOp();
- } else if (u instanceof ThrowStmt) {
- base = ((ThrowStmt)u).getOp();
- } else if (u instanceof MonitorStmt) {
- base = ((MonitorStmt)u).getOp();
- }
-
- if (base != null &&
- base instanceof Local &&
- base.getType() instanceof RefLikeType)
- addGen(u, base);
- }
- }
-
- // Call superclass method to do work.
- doAnalysis();
- }
-}
-
projects / org.ibex.arenaj.git / blobdiff