Examples with UnitValueBoxPair soot.toolkits.scalar.UnitValueBoxPair used on opensource projects

Example 6 with UnitValueBoxPair

use of soot.toolkits.scalar.UnitValueBoxPair in project soot by Sable.

the class UseChecker method caseAssignStmt.

public void caseAssignStmt(AssignStmt stmt) {
    Value lhs = stmt.getLeftOp();
    Value rhs = stmt.getRightOp();
    Type tlhs = null;
    if (lhs instanceof Local)
        tlhs = this.tg.get((Local) lhs);
    else if (lhs instanceof ArrayRef) {
        ArrayRef aref = (ArrayRef) lhs;
        Local base = (Local) aref.getBase();
        // Try to force Type integrity. The left side must agree on the
        // element type of the right side array reference.
        ArrayType at = null;
        Type tgType = this.tg.get(base);
        if (tgType instanceof ArrayType)
            at = (ArrayType) tgType;
        else {
            // is java.lang.Object
            if (tgType == Scene.v().getObjectType() && rhs instanceof Local) {
                Type rhsType = this.tg.get((Local) rhs);
                if (rhsType instanceof PrimType) {
                    if (defs == null) {
                        defs = LocalDefs.Factory.newLocalDefs(jb);
                        uses = LocalUses.Factory.newLocalUses(jb, defs);
                    }
                    // Check the original type of the array from the alloc site
                    for (Unit defU : defs.getDefsOfAt(base, stmt)) {
                        if (defU instanceof AssignStmt) {
                            AssignStmt defUas = (AssignStmt) defU;
                            if (defUas.getRightOp() instanceof NewArrayExpr) {
                                at = (ArrayType) defUas.getRightOp().getType();
                                break;
                            }
                        }
                    }
                }
            }
            if (at == null)
                at = tgType.makeArrayType();
        }
        tlhs = ((ArrayType) at).getElementType();
        this.handleArrayRef(aref, stmt);
        aref.setBase((Local) this.uv.visit(aref.getBase(), at, stmt));
        stmt.setRightOp(this.uv.visit(rhs, tlhs, stmt));
        stmt.setLeftOp(this.uv.visit(lhs, tlhs, stmt));
    } else if (lhs instanceof FieldRef) {
        tlhs = ((FieldRef) lhs).getFieldRef().type();
        if (lhs instanceof InstanceFieldRef)
            this.handleInstanceFieldRef((InstanceFieldRef) lhs, stmt);
    }
    // They may have been changed above
    lhs = stmt.getLeftOp();
    rhs = stmt.getRightOp();
    if (rhs instanceof Local)
        stmt.setRightOp(this.uv.visit(rhs, tlhs, stmt));
    else if (rhs instanceof ArrayRef) {
        ArrayRef aref = (ArrayRef) rhs;
        Local base = (Local) aref.getBase();
        // try to force Type integrity
        ArrayType at = null;
        Type et = null;
        if (this.tg.get(base) instanceof ArrayType)
            at = (ArrayType) this.tg.get(base);
        else {
            Type bt = this.tg.get(base);
            // For some fixed type T, we assume that we can fix the array to T[].
            if (bt instanceof RefType || bt instanceof NullType) {
                RefType rt = bt instanceof NullType ? null : (RefType) bt;
                if (rt == null || rt.getSootClass().getName().equals("java.lang.Object") || rt.getSootClass().getName().equals("java.io.Serializable") || rt.getSootClass().getName().equals("java.lang.Cloneable")) {
                    if (defs == null) {
                        defs = LocalDefs.Factory.newLocalDefs(jb);
                        uses = LocalUses.Factory.newLocalUses(jb, defs);
                    }
                    outer: for (UnitValueBoxPair usePair : uses.getUsesOf(stmt)) {
                        Stmt useStmt = (Stmt) usePair.getUnit();
                        // from the callee's signature=
                        if (useStmt.containsInvokeExpr()) {
                            for (int i = 0; i < useStmt.getInvokeExpr().getArgCount(); i++) {
                                if (useStmt.getInvokeExpr().getArg(i) == usePair.getValueBox().getValue()) {
                                    et = useStmt.getInvokeExpr().getMethod().getParameterType(i);
                                    at = et.makeArrayType();
                                    break outer;
                                }
                            }
                        } else // if the other value is a primitive.
                        if (useStmt instanceof IfStmt) {
                            IfStmt ifStmt = (IfStmt) useStmt;
                            if (ifStmt.getCondition() instanceof EqExpr) {
                                EqExpr expr = (EqExpr) ifStmt.getCondition();
                                final Value other;
                                if (expr.getOp1() == usePair.getValueBox().getValue())
                                    other = expr.getOp2();
                                else
                                    other = expr.getOp1();
                                Type newEt = getTargetType(other);
                                if (newEt != null)
                                    et = newEt;
                            }
                        } else if (useStmt instanceof AssignStmt) {
                            // For binary expressions, we can look for type information in the
                            // other operands
                            AssignStmt useAssignStmt = (AssignStmt) useStmt;
                            if (useAssignStmt.getRightOp() instanceof BinopExpr) {
                                BinopExpr binOp = (BinopExpr) useAssignStmt.getRightOp();
                                final Value other;
                                if (binOp.getOp1() == usePair.getValueBox().getValue())
                                    other = binOp.getOp2();
                                else
                                    other = binOp.getOp1();
                                Type newEt = getTargetType(other);
                                if (newEt != null)
                                    et = newEt;
                            }
                        } else if (useStmt instanceof ReturnStmt) {
                            et = jb.getMethod().getReturnType();
                        }
                    }
                }
            }
            if (at == null)
                at = et.makeArrayType();
        }
        Type trhs = ((ArrayType) at).getElementType();
        this.handleArrayRef(aref, stmt);
        aref.setBase((Local) this.uv.visit(aref.getBase(), at, stmt));
        stmt.setRightOp(this.uv.visit(rhs, trhs, stmt));
    } else if (rhs instanceof InstanceFieldRef) {
        this.handleInstanceFieldRef((InstanceFieldRef) rhs, stmt);
        stmt.setRightOp(this.uv.visit(rhs, tlhs, stmt));
    } else if (rhs instanceof BinopExpr)
        this.handleBinopExpr((BinopExpr) rhs, stmt, tlhs);
    else if (rhs instanceof InvokeExpr) {
        this.handleInvokeExpr((InvokeExpr) rhs, stmt);
        stmt.setRightOp(this.uv.visit(rhs, tlhs, stmt));
    } else if (rhs instanceof CastExpr)
        stmt.setRightOp(this.uv.visit(rhs, tlhs, stmt));
    else if (rhs instanceof InstanceOfExpr) {
        InstanceOfExpr ioe = (InstanceOfExpr) rhs;
        ioe.setOp(this.uv.visit(ioe.getOp(), RefType.v("java.lang.Object"), stmt));
        stmt.setRightOp(this.uv.visit(rhs, tlhs, stmt));
    } else if (rhs instanceof NewArrayExpr) {
        NewArrayExpr nae = (NewArrayExpr) rhs;
        nae.setSize(this.uv.visit(nae.getSize(), IntType.v(), stmt));
        stmt.setRightOp(this.uv.visit(rhs, tlhs, stmt));
    } else if (rhs instanceof NewMultiArrayExpr) {
        NewMultiArrayExpr nmae = (NewMultiArrayExpr) rhs;
        for (int i = 0; i < nmae.getSizeCount(); i++) nmae.setSize(i, this.uv.visit(nmae.getSize(i), IntType.v(), stmt));
        stmt.setRightOp(this.uv.visit(rhs, tlhs, stmt));
    } else if (rhs instanceof LengthExpr) {
        stmt.setRightOp(this.uv.visit(rhs, tlhs, stmt));
    } else if (rhs instanceof NegExpr) {
        ((NegExpr) rhs).setOp(this.uv.visit(((NegExpr) rhs).getOp(), tlhs, stmt));
    } else if (rhs instanceof Constant)
        if (!(rhs instanceof NullConstant))
            stmt.setRightOp(this.uv.visit(rhs, tlhs, stmt));
}