Examples with InstanceFieldRef soot.jimple.InstanceFieldRef used on opensource projects

Example 6 with InstanceFieldRef

use of soot.jimple.InstanceFieldRef in project soot by Sable.

the class LockAllocationBodyTransformer method getLockFor.

public static Value getLockFor(EquivalentValue lockEqVal) {
    Value lock = lockEqVal.getValue();
    if (lock instanceof InstanceFieldRef)
        return lock;
    if (// it would be better to lock the array
    lock instanceof ArrayRef)
        // ref for each value of the index!
        return ((ArrayRef) lock).getBase();
    if (lock instanceof Local)
        return lock;
    if (lock instanceof StaticFieldRef || lock instanceof NewStaticLock) {
        if (lockEqValToLock.containsKey(lockEqVal))
            return lockEqValToLock.get(lockEqVal);
        SootClass lockClass = null;
        if (lock instanceof StaticFieldRef) {
            StaticFieldRef sfrLock = (StaticFieldRef) lock;
            lockClass = sfrLock.getField().getDeclaringClass();
        } else if (lock instanceof NewStaticLock) {
            DeadlockAvoidanceEdge dae = (DeadlockAvoidanceEdge) lock;
            lockClass = dae.getLockClass();
        }
        SootMethod clinitMethod = null;
        JimpleBody clinitBody = null;
        Stmt firstStmt = null;
        boolean addingNewClinit = !lockClass.declaresMethod("void <clinit>()");
        if (addingNewClinit) {
            clinitMethod = Scene.v().makeSootMethod("<clinit>", new ArrayList(), VoidType.v(), Modifier.PUBLIC | Modifier.STATIC);
            clinitBody = Jimple.v().newBody(clinitMethod);
            clinitMethod.setActiveBody(clinitBody);
            lockClass.addMethod(clinitMethod);
        } else {
            clinitMethod = lockClass.getMethod("void <clinit>()");
            clinitBody = (JimpleBody) clinitMethod.getActiveBody();
            firstStmt = clinitBody.getFirstNonIdentityStmt();
        }
        PatchingChain<Unit> clinitUnits = clinitBody.getUnits();
        Local lockLocal = Jimple.v().newLocal("objectLockLocal" + lockNumber, RefType.v("java.lang.Object"));
        // lockNumber is increased below
        // TODO: add name conflict
        clinitBody.getLocals().add(lockLocal);
        // avoidance code
        // assign new object to lock obj
        Stmt newStmt = Jimple.v().newAssignStmt(lockLocal, Jimple.v().newNewExpr(RefType.v("java.lang.Object")));
        if (addingNewClinit)
            clinitUnits.add(newStmt);
        else
            clinitUnits.insertBeforeNoRedirect(newStmt, firstStmt);
        // initialize new object
        SootClass objectClass = Scene.v().loadClassAndSupport("java.lang.Object");
        RefType type = RefType.v(objectClass);
        SootMethod initMethod = objectClass.getMethod("void <init>()");
        Stmt initStmt = Jimple.v().newInvokeStmt(Jimple.v().newSpecialInvokeExpr(lockLocal, initMethod.makeRef(), Collections.EMPTY_LIST));
        if (addingNewClinit)
            clinitUnits.add(initStmt);
        else
            clinitUnits.insertBeforeNoRedirect(initStmt, firstStmt);
        // copy new object to global static lock object (for use by other
        // fns)
        SootField actualLockObject = Scene.v().makeSootField("objectLockGlobal" + lockNumber, RefType.v("java.lang.Object"), Modifier.STATIC | Modifier.PUBLIC);
        lockNumber++;
        lockClass.addField(actualLockObject);
        StaticFieldRef actualLockSfr = Jimple.v().newStaticFieldRef(actualLockObject.makeRef());
        Stmt assignStmt = Jimple.v().newAssignStmt(actualLockSfr, lockLocal);
        if (addingNewClinit)
            clinitUnits.add(assignStmt);
        else
            clinitUnits.insertBeforeNoRedirect(assignStmt, firstStmt);
        if (addingNewClinit)
            clinitUnits.add(Jimple.v().newReturnVoidStmt());
        lockEqValToLock.put(lockEqVal, actualLockSfr);
        return actualLockSfr;
    }
    throw new RuntimeException("Unknown type of lock (" + lock + "): expected FieldRef, ArrayRef, or Local");
}

Example 7 with InstanceFieldRef

use of soot.jimple.InstanceFieldRef in project soot by Sable.

the class ConstraintCollector method caseAssignStmt.

public void caseAssignStmt(AssignStmt stmt) {
    Value l = stmt.getLeftOp();
    Value r = stmt.getRightOp();
    TypeVariable left = null;
    TypeVariable right = null;
    if (l instanceof ArrayRef) {
        ArrayRef ref = (ArrayRef) l;
        Type baset = ((Local) ref.getBase()).getType();
        if (baset instanceof ArrayType) {
            ArrayType base = (ArrayType) baset;
            Value index = ref.getIndex();
            if (uses) {
                if ((base.numDimensions == 1) && (base.baseType instanceof IntegerType)) {
                    left = resolver.typeVariable(base.baseType);
                }
                if (index instanceof Local) {
                    resolver.typeVariable((Local) index).addParent(resolver.INT);
                }
            }
        }
    } else if (l instanceof Local) {
        if (((Local) l).getType() instanceof IntegerType) {
            left = resolver.typeVariable((Local) l);
        }
    } else if (l instanceof InstanceFieldRef) {
        if (uses) {
            InstanceFieldRef ref = (InstanceFieldRef) l;
            Type fieldType = ref.getFieldRef().type();
            if (fieldType instanceof IntegerType) {
                left = resolver.typeVariable(ref.getFieldRef().type());
            }
        }
    } else if (l instanceof StaticFieldRef) {
        if (uses) {
            StaticFieldRef ref = (StaticFieldRef) l;
            Type fieldType = ref.getFieldRef().type();
            if (fieldType instanceof IntegerType) {
                left = resolver.typeVariable(ref.getFieldRef().type());
            }
        }
    } else {
        throw new RuntimeException("Unhandled assignment left hand side type: " + l.getClass());
    }
    if (r instanceof ArrayRef) {
        ArrayRef ref = (ArrayRef) r;
        Type baset = ((Local) ref.getBase()).getType();
        if (!(baset instanceof NullType)) {
            Value index = ref.getIndex();
            // Be careful, dex can do some weird object/array casting
            if (baset instanceof ArrayType) {
                ArrayType base = (ArrayType) baset;
                if ((base.numDimensions == 1) && (base.baseType instanceof IntegerType)) {
                    right = resolver.typeVariable(base.baseType);
                }
            } else if (baset instanceof IntegerType)
                right = resolver.typeVariable(baset);
            if (uses)
                if (index instanceof Local)
                    resolver.typeVariable((Local) index).addParent(resolver.INT);
        }
    } else if (r instanceof DoubleConstant) {
    } else if (r instanceof FloatConstant) {
    } else if (r instanceof IntConstant) {
        int value = ((IntConstant) r).value;
        if (value < -32768) {
            right = resolver.INT;
        } else if (value < -128) {
            right = resolver.SHORT;
        } else if (value < 0) {
            right = resolver.BYTE;
        } else if (value < 2) {
            right = resolver.R0_1;
        } else if (value < 128) {
            right = resolver.R0_127;
        } else if (value < 32768) {
            right = resolver.R0_32767;
        } else if (value < 65536) {
            right = resolver.CHAR;
        } else {
            right = resolver.INT;
        }
    } else if (r instanceof LongConstant) {
    } else if (r instanceof NullConstant) {
    } else if (r instanceof StringConstant) {
    } else if (r instanceof ClassConstant) {
    } else if (r instanceof BinopExpr) {
        // ******** BINOP EXPR ********
        BinopExpr be = (BinopExpr) r;
        Value lv = be.getOp1();
        Value rv = be.getOp2();
        TypeVariable lop = null;
        TypeVariable rop = null;
        // ******** LEFT ********
        if (lv instanceof Local) {
            if (((Local) lv).getType() instanceof IntegerType) {
                lop = resolver.typeVariable((Local) lv);
            }
        } else if (lv instanceof DoubleConstant) {
        } else if (lv instanceof FloatConstant) {
        } else if (lv instanceof IntConstant) {
            int value = ((IntConstant) lv).value;
            if (value < -32768) {
                lop = resolver.INT;
            } else if (value < -128) {
                lop = resolver.SHORT;
            } else if (value < 0) {
                lop = resolver.BYTE;
            } else if (value < 2) {
                lop = resolver.R0_1;
            } else if (value < 128) {
                lop = resolver.R0_127;
            } else if (value < 32768) {
                lop = resolver.R0_32767;
            } else if (value < 65536) {
                lop = resolver.CHAR;
            } else {
                lop = resolver.INT;
            }
        } else if (lv instanceof LongConstant) {
        } else if (lv instanceof NullConstant) {
        } else if (lv instanceof StringConstant) {
        } else if (lv instanceof ClassConstant) {
        } else {
            throw new RuntimeException("Unhandled binary expression left operand type: " + lv.getClass());
        }
        // ******** RIGHT ********
        if (rv instanceof Local) {
            if (((Local) rv).getType() instanceof IntegerType) {
                rop = resolver.typeVariable((Local) rv);
            }
        } else if (rv instanceof DoubleConstant) {
        } else if (rv instanceof FloatConstant) {
        } else if (rv instanceof IntConstant) {
            int value = ((IntConstant) rv).value;
            if (value < -32768) {
                rop = resolver.INT;
            } else if (value < -128) {
                rop = resolver.SHORT;
            } else if (value < 0) {
                rop = resolver.BYTE;
            } else if (value < 2) {
                rop = resolver.R0_1;
            } else if (value < 128) {
                rop = resolver.R0_127;
            } else if (value < 32768) {
                rop = resolver.R0_32767;
            } else if (value < 65536) {
                rop = resolver.CHAR;
            } else {
                rop = resolver.INT;
            }
        } else if (rv instanceof LongConstant) {
        } else if (rv instanceof NullConstant) {
        } else if (rv instanceof StringConstant) {
        } else if (rv instanceof ClassConstant) {
        } else {
            throw new RuntimeException("Unhandled binary expression right operand type: " + rv.getClass());
        }
        if ((be instanceof AddExpr) || (be instanceof SubExpr) || (be instanceof DivExpr) || (be instanceof RemExpr) || (be instanceof MulExpr)) {
            if (lop != null && rop != null) {
                if (uses) {
                    if (lop.type() == null) {
                        lop.addParent(resolver.INT);
                    }
                    if (rop.type() == null) {
                        rop.addParent(resolver.INT);
                    }
                }
                right = resolver.INT;
            }
        } else if ((be instanceof AndExpr) || (be instanceof OrExpr) || (be instanceof XorExpr)) {
            if (lop != null && rop != null) {
                TypeVariable common = resolver.typeVariable();
                if (rop != null)
                    rop.addParent(common);
                if (lop != null)
                    lop.addParent(common);
                right = common;
            }
        } else if (be instanceof ShlExpr) {
            if (uses) {
                if (lop != null && lop.type() == null) {
                    lop.addParent(resolver.INT);
                }
                if (rop.type() == null) {
                    rop.addParent(resolver.INT);
                }
            }
            right = (lop == null) ? null : resolver.INT;
        } else if ((be instanceof ShrExpr) || (be instanceof UshrExpr)) {
            if (uses) {
                if (lop != null && lop.type() == null) {
                    lop.addParent(resolver.INT);
                }
                if (rop.type() == null) {
                    rop.addParent(resolver.INT);
                }
            }
            right = lop;
        } else if ((be instanceof CmpExpr) || (be instanceof CmpgExpr) || (be instanceof CmplExpr)) {
            right = resolver.BYTE;
        } else if ((be instanceof EqExpr) || (be instanceof GeExpr) || (be instanceof GtExpr) || (be instanceof LeExpr) || (be instanceof LtExpr) || (be instanceof NeExpr)) {
            if (uses) {
                TypeVariable common = resolver.typeVariable();
                if (rop != null)
                    rop.addParent(common);
                if (lop != null)
                    lop.addParent(common);
            }
            right = resolver.BOOLEAN;
        } else {
            throw new RuntimeException("Unhandled binary expression type: " + be.getClass());
        }
    } else if (r instanceof CastExpr) {
        CastExpr ce = (CastExpr) r;
        if (ce.getCastType() instanceof IntegerType) {
            right = resolver.typeVariable(ce.getCastType());
        }
    } else if (r instanceof InstanceOfExpr) {
        right = resolver.BOOLEAN;
    } else if (r instanceof InvokeExpr) {
        InvokeExpr ie = (InvokeExpr) r;
        handleInvokeExpr(ie);
        if (ie.getMethodRef().returnType() instanceof IntegerType) {
            right = resolver.typeVariable(ie.getMethodRef().returnType());
        }
    } else if (r instanceof NewArrayExpr) {
        NewArrayExpr nae = (NewArrayExpr) r;
        if (uses) {
            Value size = nae.getSize();
            if (size instanceof Local) {
                TypeVariable var = resolver.typeVariable((Local) size);
                var.addParent(resolver.INT);
            }
        }
    } else if (r instanceof NewExpr) {
    } else if (r instanceof NewMultiArrayExpr) {
        NewMultiArrayExpr nmae = (NewMultiArrayExpr) r;
        if (uses) {
            for (int i = 0; i < nmae.getSizeCount(); i++) {
                Value size = nmae.getSize(i);
                if (size instanceof Local) {
                    TypeVariable var = resolver.typeVariable((Local) size);
                    var.addParent(resolver.INT);
                }
            }
        }
    } else if (r instanceof LengthExpr) {
        right = resolver.INT;
    } else if (r instanceof NegExpr) {
        NegExpr ne = (NegExpr) r;
        if (ne.getOp() instanceof Local) {
            Local local = (Local) ne.getOp();
            if (local.getType() instanceof IntegerType) {
                if (uses) {
                    resolver.typeVariable(local).addParent(resolver.INT);
                }
                TypeVariable v = resolver.typeVariable();
                v.addChild(resolver.BYTE);
                v.addChild(resolver.typeVariable(local));
                right = v;
            }
        } else if (ne.getOp() instanceof DoubleConstant) {
        } else if (ne.getOp() instanceof FloatConstant) {
        } else if (ne.getOp() instanceof IntConstant) {
            int value = ((IntConstant) ne.getOp()).value;
            if (value < -32768) {
                right = resolver.INT;
            } else if (value < -128) {
                right = resolver.SHORT;
            } else if (value < 0) {
                right = resolver.BYTE;
            } else if (value < 2) {
                right = resolver.BYTE;
            } else if (value < 128) {
                right = resolver.BYTE;
            } else if (value < 32768) {
                right = resolver.SHORT;
            } else if (value < 65536) {
                right = resolver.INT;
            } else {
                right = resolver.INT;
            }
        } else if (ne.getOp() instanceof LongConstant) {
        } else {
            throw new RuntimeException("Unhandled neg expression operand type: " + ne.getOp().getClass());
        }
    } else if (r instanceof Local) {
        Local local = (Local) r;
        if (local.getType() instanceof IntegerType) {
            right = resolver.typeVariable(local);
        }
    } else if (r instanceof InstanceFieldRef) {
        InstanceFieldRef ref = (InstanceFieldRef) r;
        if (ref.getFieldRef().type() instanceof IntegerType) {
            right = resolver.typeVariable(ref.getFieldRef().type());
        }
    } else if (r instanceof StaticFieldRef) {
        StaticFieldRef ref = (StaticFieldRef) r;
        if (ref.getFieldRef().type() instanceof IntegerType) {
            right = resolver.typeVariable(ref.getFieldRef().type());
        }
    } else {
        throw new RuntimeException("Unhandled assignment right hand side type: " + r.getClass());
    }
    if (left != null && right != null && (left.type() == null || right.type() == null)) {
        right.addParent(left);
    }
}

Example 8 with InstanceFieldRef

use of soot.jimple.InstanceFieldRef in project soot by Sable.

the class ArrayIndexLivenessAnalysis method getGenAndKillSetForDefnStmt.

private void getGenAndKillSetForDefnStmt(DefinitionStmt asstmt, HashMap<Stmt, HashSet<Value>> absgen, HashSet<Object> genset, HashSet<Value> absgenset, HashSet<Value> killset, HashSet<Value> condset) {
    /* kill left hand side */
    Value lhs = asstmt.getLeftOp();
    Value rhs = asstmt.getRightOp();
    boolean killarrayrelated = false;
    boolean killallarrayref = false;
    if (fieldin) {
        if (lhs instanceof Local) {
            HashSet<Value> related = localToFieldRef.get(lhs);
            if (related != null)
                killset.addAll(related);
        } else if (lhs instanceof StaticFieldRef) {
            killset.add(lhs);
            condset.add(lhs);
        } else if (lhs instanceof InstanceFieldRef) {
            SootField field = ((InstanceFieldRef) lhs).getField();
            HashSet<Value> related = fieldToFieldRef.get(field);
            if (related != null)
                killset.addAll(related);
            condset.add(lhs);
        }
        if (asstmt.containsInvokeExpr()) {
            /*
                Value expr = asstmt.getInvokeExpr();
                List parameters = ((InvokeExpr)expr).getArgs();

                // add the method invocation
                boolean killall = false;
                if (expr instanceof InstanceInvokeExpr)
                    killall = true;
                else
                {
                    for (int i=0; i<parameters.size(); i++)
                    {
                    Value para = (Value)parameters.get(i);
                    if (para.getType() instanceof RefType)
                    {
                        killall = true;
                        break;
                    }
                    }
                }
    
                if (killall)
                {
                    killset.addAll(allInstFieldRefs);
                }   
                */
            killset.addAll(allFieldRefs);
        }
    }
    if (arrayin) {
        // a = ... or i = ...
        if (lhs instanceof Local) {
            killarrayrelated = true;
        } else // a[i] = ...
        if (lhs instanceof ArrayRef) {
            killallarrayref = true;
            condset.add(lhs);
        }
        // invokeexpr kills all array references.
        if (asstmt.containsInvokeExpr()) {
            killallarrayref = true;
        }
    }
    if (csin) {
        HashSet<Value> exprs = localToExpr.get(lhs);
        if (exprs != null)
            killset.addAll(exprs);
        if (rhs instanceof BinopExpr) {
            Value op1 = ((BinopExpr) rhs).getOp1();
            Value op2 = ((BinopExpr) rhs).getOp2();
            if (rhs instanceof AddExpr) {
                if ((op1 instanceof Local) && (op2 instanceof Local))
                    genset.add(rhs);
            } else if (rhs instanceof MulExpr) {
                if ((op1 instanceof Local) || (op2 instanceof Local))
                    genset.add(rhs);
            } else if (rhs instanceof SubExpr) {
                if (op2 instanceof Local)
                    genset.add(rhs);
            }
        }
    }
    if ((lhs instanceof Local) && (fullSet.contains(lhs))) {
        killset.add(lhs);
        /* speculatively add lhs as live condition. */
        condset.add(lhs);
    } else if (lhs instanceof ArrayRef) {
        /* a[i] generate a and i. */
        Value base = ((ArrayRef) lhs).getBase();
        Value index = ((ArrayRef) lhs).getIndex();
        absgenset.add(base);
        if (index instanceof Local) {
            absgenset.add(index);
        }
    }
    if (rhs instanceof Local) {
        /*
              if (lhs instanceof Local && fullSet.contains(rhs))
              genset.add(rhs);
            */
        if (fullSet.contains(rhs))
            genset.add(rhs);
    /*
              if (fieldin && (lhs instanceof FieldRef))
              genset.add(rhs);
            */
    } else if (rhs instanceof FieldRef) {
        if (fieldin)
            genset.add(rhs);
    } else if (rhs instanceof ArrayRef) {
        /* lhs=a[i]. */
        Value base = ((ArrayRef) rhs).getBase();
        Value index = ((ArrayRef) rhs).getIndex();
        absgenset.add(base);
        if (index instanceof Local) {
            absgenset.add(index);
        }
        if (arrayin) {
            genset.add(rhs);
            if (rectarray)
                genset.add(Array2ndDimensionSymbol.v(base));
        }
    } else if (rhs instanceof NewArrayExpr) {
        /* a = new A[i]; */
        Value size = ((NewArrayExpr) rhs).getSize();
        if (size instanceof Local)
            genset.add(size);
    } else if (rhs instanceof NewMultiArrayExpr) {
        /* a = new A[i][]...;*/
        /* More precisely, we should track other dimensions. */
        List sizes = ((NewMultiArrayExpr) rhs).getSizes();
        Iterator sizeIt = sizes.iterator();
        while (sizeIt.hasNext()) {
            Value size = (Value) sizeIt.next();
            if (size instanceof Local)
                genset.add(size);
        }
    } else if (rhs instanceof LengthExpr) {
        /* lhs = lengthof rhs */
        Value op = ((LengthExpr) rhs).getOp();
        genset.add(op);
    } else if (rhs instanceof JAddExpr) {
        /* lhs = rhs+c, lhs=c+rhs */
        Value op1 = ((JAddExpr) rhs).getOp1();
        Value op2 = ((JAddExpr) rhs).getOp2();
        if ((op1 instanceof IntConstant) && (op2 instanceof Local)) {
            genset.add(op2);
        } else if ((op2 instanceof IntConstant) && (op1 instanceof Local)) {
            genset.add(op1);
        }
    } else if (rhs instanceof JSubExpr) {
        Value op1 = ((JSubExpr) rhs).getOp1();
        Value op2 = ((JSubExpr) rhs).getOp2();
        if ((op1 instanceof Local) && (op2 instanceof IntConstant)) {
            genset.add(op1);
        }
    }
    if (arrayin) {
        if (killarrayrelated)
            killArrayRelated.put(asstmt, lhs);
        if (killallarrayref)
            killAllArrayRef.put(asstmt, new Boolean(true));
    }
}

Example 9 with InstanceFieldRef

use of soot.jimple.InstanceFieldRef in project soot by Sable.

the class ArrayIndexLivenessAnalysis method getAllRelatedMaps.

private void getAllRelatedMaps(Body body) {
    Iterator unitIt = body.getUnits().iterator();
    while (unitIt.hasNext()) {
        Stmt stmt = (Stmt) unitIt.next();
        if (csin) {
            if (stmt instanceof DefinitionStmt) {
                Value rhs = ((DefinitionStmt) stmt).getRightOp();
                if (rhs instanceof BinopExpr) {
                    Value op1 = ((BinopExpr) rhs).getOp1();
                    Value op2 = ((BinopExpr) rhs).getOp2();
                    if (rhs instanceof AddExpr) {
                        // op1 + op2 --> a + b
                        if ((op1 instanceof Local) && (op2 instanceof Local)) {
                            HashSet<Value> refs = localToExpr.get(op1);
                            if (refs == null) {
                                refs = new HashSet<Value>();
                                localToExpr.put(op1, refs);
                            }
                            refs.add(rhs);
                            refs = localToExpr.get(op2);
                            if (refs == null) {
                                refs = new HashSet<Value>();
                                localToExpr.put(op2, refs);
                            }
                            refs.add(rhs);
                        }
                    } else // a * b, a * c, c * a
                    if (rhs instanceof MulExpr) {
                        HashSet<Value> refs = localToExpr.get(op1);
                        if (refs == null) {
                            refs = new HashSet<Value>();
                            localToExpr.put(op1, refs);
                        }
                        refs.add(rhs);
                        refs = localToExpr.get(op2);
                        if (refs == null) {
                            refs = new HashSet<Value>();
                            localToExpr.put(op2, refs);
                        }
                        refs.add(rhs);
                    } else if (rhs instanceof SubExpr) {
                        if (op2 instanceof Local) {
                            HashSet<Value> refs = localToExpr.get(op2);
                            if (refs == null) {
                                refs = new HashSet<Value>();
                                localToExpr.put(op2, refs);
                            }
                            refs.add(rhs);
                            if (op1 instanceof Local) {
                                refs = localToExpr.get(op1);
                                if (refs == null) {
                                    refs = new HashSet<Value>();
                                    localToExpr.put(op1, refs);
                                }
                                refs.add(rhs);
                            }
                        }
                    }
                }
            }
        }
        for (ValueBox vbox : stmt.getUseAndDefBoxes()) {
            Value v = vbox.getValue();
            if (fieldin) {
                if (v instanceof InstanceFieldRef) {
                    Value base = ((InstanceFieldRef) v).getBase();
                    SootField field = ((InstanceFieldRef) v).getField();
                    HashSet<Value> baseset = localToFieldRef.get(base);
                    if (baseset == null) {
                        baseset = new HashSet<Value>();
                        localToFieldRef.put(base, baseset);
                    }
                    baseset.add(v);
                    HashSet<Value> fieldset = fieldToFieldRef.get(field);
                    if (fieldset == null) {
                        fieldset = new HashSet<Value>();
                        fieldToFieldRef.put(field, fieldset);
                    }
                    fieldset.add(v);
                }
                if (v instanceof FieldRef)
                    allFieldRefs.add(v);
            }
            if (arrayin) {
            // a = ...   --> kill all a[x] nodes.
            // a[i] = .. --> kill all array references.
            // m(a)      --> kill all array references
            // i = ...   --> kill all array reference with index as i
            /*
                if (v instanceof ArrayRef)
                {
                    Value base = ((ArrayRef)v).getBase();
                    Value index = ((ArrayRef)v).getIndex();

                    HashSet refset = (HashSet)localToArrayRef.get(base);
                    if (refset == null)
                    {
                        refset = new HashSet();
                        localToArrayRef.put(base, refset);
                    }
                    refset.add(v);

                    if (index instanceof Local)
                    {
                        refset = (HashSet)localToArrayRef.get(index);
                        if (refset == null)
                        {
                            refset = new HashSet();
                            localToArrayRef.put(index, refset);
                        }

                        refset.add(v);
                    }           
                    allArrayRefs.add(v);
                }
                */
            }
        }
    }
}

Example 10 with InstanceFieldRef

use of soot.jimple.InstanceFieldRef in project soot by Sable.

the class DeadAssignmentEliminator method internalTransform.

/**
 * Eliminates dead code in a linear fashion.  Complexity is linear
 * with respect to the statements.
 *
 * Does not work on grimp code because of the check on the right hand
 * side for side effects.
 */
@Override
protected void internalTransform(Body b, String phaseName, Map<String, String> options) {
    boolean eliminateOnlyStackLocals = PhaseOptions.getBoolean(options, "only-stack-locals");
    final Options soptions = Options.v();
    if (soptions.verbose()) {
        logger.debug("[" + b.getMethod().getName() + "] Eliminating dead code...");
    }
    if (soptions.time()) {
        Timers.v().deadCodeTimer.start();
    }
    Chain<Unit> units = b.getUnits();
    Deque<Unit> q = new ArrayDeque<Unit>(units.size());
    // Make a first pass through the statements, noting
    // the statements we must absolutely keep.
    boolean isStatic = b.getMethod().isStatic();
    boolean allEssential = true;
    boolean checkInvoke = false;
    Local thisLocal = null;
    for (Iterator<Unit> it = units.iterator(); it.hasNext(); ) {
        Unit s = it.next();
        boolean isEssential = true;
        if (s instanceof NopStmt) {
            // Hack: do not remove nop if is is used for a Trap
            // which is at the very end of the code.
            boolean removeNop = it.hasNext();
            if (!removeNop) {
                removeNop = true;
                for (Trap t : b.getTraps()) {
                    if (t.getEndUnit() == s) {
                        removeNop = false;
                        break;
                    }
                }
            }
            if (removeNop) {
                it.remove();
                continue;
            }
        } else if (s instanceof AssignStmt) {
            AssignStmt as = (AssignStmt) s;
            Value lhs = as.getLeftOp();
            Value rhs = as.getRightOp();
            // Stmt is of the form a = a which is useless
            if (lhs == rhs && lhs instanceof Local) {
                it.remove();
                continue;
            }
            if (lhs instanceof Local && (!eliminateOnlyStackLocals || ((Local) lhs).getName().startsWith("$") || lhs.getType() instanceof NullType)) {
                isEssential = false;
                if (!checkInvoke) {
                    checkInvoke = as.containsInvokeExpr();
                }
                if (rhs instanceof CastExpr) {
                    // CastExpr          : can trigger ClassCastException, but null-casts never fail
                    CastExpr ce = (CastExpr) rhs;
                    Type t = ce.getCastType();
                    Value v = ce.getOp();
                    isEssential = !(v instanceof NullConstant && t instanceof RefType);
                } else if (rhs instanceof InvokeExpr || rhs instanceof ArrayRef || rhs instanceof NewExpr || rhs instanceof NewArrayExpr || rhs instanceof NewMultiArrayExpr) {
                    // ArrayRef          : can have side effects (like throwing a null pointer exception)
                    // InvokeExpr        : can have side effects (like throwing a null pointer exception)
                    // NewArrayExpr      : can throw exception
                    // NewMultiArrayExpr : can throw exception
                    // NewExpr           : can trigger class initialization
                    isEssential = true;
                } else if (rhs instanceof FieldRef) {
                    // Can trigger class initialization
                    isEssential = true;
                    if (rhs instanceof InstanceFieldRef) {
                        InstanceFieldRef ifr = (InstanceFieldRef) rhs;
                        if (!isStatic && thisLocal == null) {
                            thisLocal = b.getThisLocal();
                        }
                        // Any InstanceFieldRef may have side effects,
                        // unless the base is reading from 'this'
                        // in a non-static method
                        isEssential = (isStatic || thisLocal != ifr.getBase());
                    }
                } else if (rhs instanceof DivExpr || rhs instanceof RemExpr) {
                    BinopExpr expr = (BinopExpr) rhs;
                    Type t1 = expr.getOp1().getType();
                    Type t2 = expr.getOp2().getType();
                    // Can trigger a division by zero
                    boolean t2Int = t2 instanceof IntType;
                    isEssential = t2Int || t1 instanceof IntType || t1 instanceof LongType || t2 instanceof LongType || t1 instanceof UnknownType || t2 instanceof UnknownType;
                    if (isEssential && t2Int) {
                        Value v = expr.getOp2();
                        if (v instanceof IntConstant) {
                            IntConstant i = (IntConstant) v;
                            isEssential = (i.value == 0);
                        } else
                            // could be 0, we don't know
                            isEssential = true;
                    }
                    if (isEssential && t2 instanceof LongType) {
                        Value v = expr.getOp2();
                        if (v instanceof LongConstant) {
                            LongConstant l = (LongConstant) v;
                            isEssential = (l.value == 0);
                        } else
                            // could be 0, we don't know
                            isEssential = true;
                    }
                }
            }
        }
        if (isEssential) {
            q.addFirst(s);
        }
        allEssential &= isEssential;
    }
    if (checkInvoke || !allEssential) {
        // Add all the statements which are used to compute values
        // for the essential statements, recursively
        final LocalDefs localDefs = LocalDefs.Factory.newLocalDefs(b);
        if (!allEssential) {
            Set<Unit> essential = new HashSet<Unit>(b.getUnits().size());
            while (!q.isEmpty()) {
                Unit s = q.removeFirst();
                if (essential.add(s)) {
                    for (ValueBox box : s.getUseBoxes()) {
                        Value v = box.getValue();
                        if (v instanceof Local) {
                            Local l = (Local) v;
                            List<Unit> defs = localDefs.getDefsOfAt(l, s);
                            if (defs != null)
                                q.addAll(defs);
                        }
                    }
                }
            }
            // Remove the dead statements
            units.retainAll(essential);
        }
        if (checkInvoke) {
            final LocalUses localUses = LocalUses.Factory.newLocalUses(b, localDefs);
            // Eliminate dead assignments from invokes such as x = f(), where
            // x is no longer used
            List<AssignStmt> postProcess = new ArrayList<AssignStmt>();
            for (Unit u : units) {
                if (u instanceof AssignStmt) {
                    AssignStmt s = (AssignStmt) u;
                    if (s.containsInvokeExpr()) {
                        // Just find one use of l which is essential
                        boolean deadAssignment = true;
                        for (UnitValueBoxPair pair : localUses.getUsesOf(s)) {
                            if (units.contains(pair.unit)) {
                                deadAssignment = false;
                                break;
                            }
                        }
                        if (deadAssignment) {
                            postProcess.add(s);
                        }
                    }
                }
            }
            final Jimple jimple = Jimple.v();
            for (AssignStmt s : postProcess) {
                // Transform it into a simple invoke.
                Stmt newInvoke = jimple.newInvokeStmt(s.getInvokeExpr());
                newInvoke.addAllTagsOf(s);
                units.swapWith(s, newInvoke);
                // If we have a callgraph, we need to fix it
                if (Scene.v().hasCallGraph())
                    Scene.v().getCallGraph().swapEdgesOutOf(s, newInvoke);
            }
        }
    }
    if (soptions.time()) {
        Timers.v().deadCodeTimer.end();
    }
}