Examples with BasicBlock com.android.dx.rop.code.BasicBlock used on opensource projects

Example 11 with BasicBlock

use of com.android.dx.rop.code.BasicBlock in project buck by facebook.

the class SsaBasicBlock method newFromRop.

/**
     * Creates a new SSA basic block from a ROP form basic block.
     *
     * @param rmeth original method
     * @param basicBlockIndex index this block will have
     * @param parent method of this block predecessor set will be
     * updated
     * @return new instance
     */
public static SsaBasicBlock newFromRop(RopMethod rmeth, int basicBlockIndex, final SsaMethod parent) {
    BasicBlockList ropBlocks = rmeth.getBlocks();
    BasicBlock bb = ropBlocks.get(basicBlockIndex);
    SsaBasicBlock result = new SsaBasicBlock(basicBlockIndex, bb.getLabel(), parent);
    InsnList ropInsns = bb.getInsns();
    result.insns.ensureCapacity(ropInsns.size());
    for (int i = 0, sz = ropInsns.size(); i < sz; i++) {
        result.insns.add(new NormalSsaInsn(ropInsns.get(i), result));
    }
    result.predecessors = SsaMethod.bitSetFromLabelList(ropBlocks, rmeth.labelToPredecessors(bb.getLabel()));
    result.successors = SsaMethod.bitSetFromLabelList(ropBlocks, bb.getSuccessors());
    result.successorList = SsaMethod.indexListFromLabelList(ropBlocks, bb.getSuccessors());
    if (result.successorList.size() != 0) {
        int primarySuccessor = bb.getPrimarySuccessor();
        result.primarySuccessor = (primarySuccessor < 0) ? -1 : ropBlocks.indexOfLabel(primarySuccessor);
    }
    return result;
}

Example 12 with BasicBlock

use of com.android.dx.rop.code.BasicBlock in project J2ME-Loader by nikita36078.

the class Ropper method addSynchExceptionHandlerBlock.

/**
 * Constructs and adds, if necessary, the catch-all exception handler
 * block to deal with unwinding the lock taken on entry to a synchronized
 * method.
 */
private void addSynchExceptionHandlerBlock() {
    if (!synchNeedsExceptionHandler) {
        /*
             * The method being converted either isn't synchronized or
             * can't possibly throw exceptions in its main body, so
             * there's no need for a synchronized method exception
             * handler.
             */
        return;
    }
    SourcePosition pos = method.makeSourcePosistion(0);
    RegisterSpec exReg = RegisterSpec.make(0, Type.THROWABLE);
    BasicBlock bb;
    Insn insn;
    InsnList insns = new InsnList(2);
    insn = new PlainInsn(Rops.opMoveException(Type.THROWABLE), pos, exReg, RegisterSpecList.EMPTY);
    insns.set(0, insn);
    insn = new ThrowingInsn(Rops.MONITOR_EXIT, pos, RegisterSpecList.make(getSynchReg()), StdTypeList.EMPTY);
    insns.set(1, insn);
    insns.setImmutable();
    int label2 = getSpecialLabel(SYNCH_CATCH_2);
    bb = new BasicBlock(getSpecialLabel(SYNCH_CATCH_1), insns, IntList.makeImmutable(label2), label2);
    addBlock(bb, IntList.EMPTY);
    insns = new InsnList(1);
    insn = new ThrowingInsn(Rops.THROW, pos, RegisterSpecList.make(exReg), StdTypeList.EMPTY);
    insns.set(0, insn);
    insns.setImmutable();
    bb = new BasicBlock(label2, insns, IntList.EMPTY, -1);
    addBlock(bb, IntList.EMPTY);
}

Example 13 with BasicBlock

use of com.android.dx.rop.code.BasicBlock in project J2ME-Loader by nikita36078.

the class Ropper method processBlock.

/**
 * Processes the given block.
 *
 * @param block {@code non-null;} block to process
 * @param frame {@code non-null;} start frame for the block
 * @param workSet {@code non-null;} bits representing work to do,
 * which this method may add to
 */
private void processBlock(ByteBlock block, Frame frame, int[] workSet) {
    // Prepare the list of caught exceptions for this block.
    ByteCatchList catches = block.getCatches();
    machine.startBlock(catches.toRopCatchList());
    /*
         * Using a copy of the given frame, simulate each instruction,
         * calling into machine for each.
         */
    frame = frame.copy();
    sim.simulate(block, frame);
    frame.setImmutable();
    int extraBlockCount = machine.getExtraBlockCount();
    ArrayList<Insn> insns = machine.getInsns();
    int insnSz = insns.size();
    /*
         * Merge the frame into each possible non-exceptional
         * successor.
         */
    int catchSz = catches.size();
    IntList successors = block.getSuccessors();
    int startSuccessorIndex;
    Subroutine calledSubroutine = null;
    if (machine.hasJsr()) {
        /*
             * If this frame ends in a JSR, only merge our frame with
             * the subroutine start, not the subroutine's return target.
             */
        startSuccessorIndex = 1;
        int subroutineLabel = successors.get(1);
        if (subroutines[subroutineLabel] == null) {
            subroutines[subroutineLabel] = new Subroutine(subroutineLabel);
        }
        subroutines[subroutineLabel].addCallerBlock(block.getLabel());
        calledSubroutine = subroutines[subroutineLabel];
    } else if (machine.hasRet()) {
        /*
             * This block ends in a ret, which means it's the final block
             * in some subroutine. Ultimately, this block will be copied
             * and inlined for each call and then disposed of.
             */
        ReturnAddress ra = machine.getReturnAddress();
        int subroutineLabel = ra.getSubroutineAddress();
        if (subroutines[subroutineLabel] == null) {
            subroutines[subroutineLabel] = new Subroutine(subroutineLabel, block.getLabel());
        } else {
            subroutines[subroutineLabel].addRetBlock(block.getLabel());
        }
        successors = subroutines[subroutineLabel].getSuccessors();
        subroutines[subroutineLabel].mergeToSuccessors(frame, workSet);
        // Skip processing below since we just did it.
        startSuccessorIndex = successors.size();
    } else if (machine.wereCatchesUsed()) {
        /*
             * If there are catches, then the first successors
             * (which will either be all of them or all but the last one)
             * are catch targets.
             */
        startSuccessorIndex = catchSz;
    } else {
        startSuccessorIndex = 0;
    }
    int succSz = successors.size();
    for (int i = startSuccessorIndex; i < succSz; i++) {
        int succ = successors.get(i);
        try {
            mergeAndWorkAsNecessary(succ, block.getLabel(), calledSubroutine, frame, workSet);
        } catch (SimException ex) {
            ex.addContext("...while merging to block " + Hex.u2(succ));
            throw ex;
        }
    }
    if ((succSz == 0) && machine.returns()) {
        /*
             * The block originally contained a return, but it has
             * been made to instead end with a goto, and we need to
             * tell it at this point that its sole successor is the
             * return block. This has to happen after the merge loop
             * above, since, at this point, the return block doesn't
             * actually exist; it gets synthesized at the end of
             * processing the original blocks.
             */
        successors = IntList.makeImmutable(getSpecialLabel(RETURN));
        succSz = 1;
    }
    int primarySucc;
    if (succSz == 0) {
        primarySucc = -1;
    } else {
        primarySucc = machine.getPrimarySuccessorIndex();
        if (primarySucc >= 0) {
            primarySucc = successors.get(primarySucc);
        }
    }
    /*
         * This variable is true only when the method is synchronized and
         * the block being processed can possibly throw an exception.
         */
    boolean synch = isSynchronized() && machine.canThrow();
    if (synch || (catchSz != 0)) {
        /*
             * Deal with exception handlers: Merge an exception-catch
             * frame into each possible exception handler, and
             * construct a new set of successors to point at the
             * exception handler setup blocks (which get synthesized
             * at the very end of processing).
             */
        boolean catchesAny = false;
        IntList newSucc = new IntList(succSz);
        for (int i = 0; i < catchSz; i++) {
            ByteCatchList.Item one = catches.get(i);
            CstType exceptionClass = one.getExceptionClass();
            int targ = one.getHandlerPc();
            catchesAny |= (exceptionClass == CstType.OBJECT);
            Frame f = frame.makeExceptionHandlerStartFrame(exceptionClass);
            try {
                mergeAndWorkAsNecessary(targ, block.getLabel(), null, f, workSet);
            } catch (SimException ex) {
                ex.addContext("...while merging exception to block " + Hex.u2(targ));
                throw ex;
            }
            /*
                 * Set up the exception handler type.
                 */
            CatchInfo handlers = catchInfos[targ];
            if (handlers == null) {
                handlers = new CatchInfo();
                catchInfos[targ] = handlers;
            }
            ExceptionHandlerSetup handler = handlers.getSetup(exceptionClass.getClassType());
            /*
                 * The synthesized exception setup block will have the label given by handler.
                 */
            newSucc.add(handler.getLabel());
        }
        if (synch && !catchesAny) {
            /*
                 * The method is synchronized and this block doesn't
                 * already have a catch-all handler, so add one to the
                 * end, both in the successors and in the throwing
                 * instruction(s) at the end of the block (which is where
                 * the caught classes live).
                 */
            newSucc.add(getSpecialLabel(SYNCH_CATCH_1));
            synchNeedsExceptionHandler = true;
            for (int i = insnSz - extraBlockCount - 1; i < insnSz; i++) {
                Insn insn = insns.get(i);
                if (insn.canThrow()) {
                    insn = insn.withAddedCatch(Type.OBJECT);
                    insns.set(i, insn);
                }
            }
        }
        if (primarySucc >= 0) {
            newSucc.add(primarySucc);
        }
        newSucc.setImmutable();
        successors = newSucc;
    }
    // Construct the final resulting block(s), and store it (them).
    int primarySuccListIndex = successors.indexOf(primarySucc);
    /*
         * If there are any extra blocks, work backwards through the
         * list of instructions, adding single-instruction blocks, and
         * resetting the successors variables as appropriate.
         */
    for (; /*extraBlockCount*/
    extraBlockCount > 0; extraBlockCount--) {
        /*
             * Some of the blocks that the RopperMachine wants added
             * are for move-result insns, and these need goto insns as well.
             */
        Insn extraInsn = insns.get(--insnSz);
        boolean needsGoto = extraInsn.getOpcode().getBranchingness() == Rop.BRANCH_NONE;
        InsnList il = new InsnList(needsGoto ? 2 : 1);
        IntList extraBlockSuccessors = successors;
        il.set(0, extraInsn);
        if (needsGoto) {
            il.set(1, new PlainInsn(Rops.GOTO, extraInsn.getPosition(), null, RegisterSpecList.EMPTY));
            /*
                 * Obviously, this block won't be throwing an exception
                 * so it should only have one successor.
                 */
            extraBlockSuccessors = IntList.makeImmutable(primarySucc);
        }
        il.setImmutable();
        int label = getAvailableLabel();
        BasicBlock bb = new BasicBlock(label, il, extraBlockSuccessors, primarySucc);
        // All of these extra blocks will be in the same subroutine
        addBlock(bb, frame.getSubroutines());
        successors = successors.mutableCopy();
        successors.set(primarySuccListIndex, label);
        successors.setImmutable();
        primarySucc = label;
    }
    Insn lastInsn = (insnSz == 0) ? null : insns.get(insnSz - 1);
    /*
         * Add a goto to the end of the block if it doesn't already
         * end with a branch, to maintain the invariant that all
         * blocks end with a branch of some sort or other. Note that
         * it is possible for there to be blocks for which no
         * instructions were ever output (e.g., only consist of pop*
         * in the original Java bytecode).
         */
    if ((lastInsn == null) || (lastInsn.getOpcode().getBranchingness() == Rop.BRANCH_NONE)) {
        SourcePosition pos = (lastInsn == null) ? SourcePosition.NO_INFO : lastInsn.getPosition();
        insns.add(new PlainInsn(Rops.GOTO, pos, null, RegisterSpecList.EMPTY));
        insnSz++;
    }
    /*
         * Construct a block for the remaining instructions (which in
         * the usual case is all of them).
         */
    InsnList il = new InsnList(insnSz);
    for (int i = 0; i < insnSz; i++) {
        il.set(i, insns.get(i));
    }
    il.setImmutable();
    BasicBlock bb = new BasicBlock(block.getLabel(), il, successors, primarySucc);
    addOrReplaceBlock(bb, frame.getSubroutines());
}

Example 14 with BasicBlock

use of com.android.dx.rop.code.BasicBlock in project J2ME-Loader by nikita36078.

the class Ropper method addSetupBlocks.

/**
 * Constructs and adds the blocks that perform setup for the rest of
 * the method. This includes a first block which merely contains
 * assignments from parameters to the same-numbered registers and
 * a possible second block which deals with synchronization.
 */
private void addSetupBlocks() {
    LocalVariableList localVariables = method.getLocalVariables();
    SourcePosition pos = method.makeSourcePosistion(0);
    Prototype desc = method.getEffectiveDescriptor();
    StdTypeList params = desc.getParameterTypes();
    int sz = params.size();
    InsnList insns = new InsnList(sz + 1);
    int at = 0;
    for (int i = 0; i < sz; i++) {
        Type one = params.get(i);
        LocalVariableList.Item local = localVariables.pcAndIndexToLocal(0, at);
        RegisterSpec result = (local == null) ? RegisterSpec.make(at, one) : RegisterSpec.makeLocalOptional(at, one, local.getLocalItem());
        Insn insn = new PlainCstInsn(Rops.opMoveParam(one), pos, result, RegisterSpecList.EMPTY, CstInteger.make(at));
        insns.set(i, insn);
        at += one.getCategory();
    }
    insns.set(sz, new PlainInsn(Rops.GOTO, pos, null, RegisterSpecList.EMPTY));
    insns.setImmutable();
    boolean synch = isSynchronized();
    int label = synch ? getSpecialLabel(SYNCH_SETUP_1) : 0;
    BasicBlock bb = new BasicBlock(getSpecialLabel(PARAM_ASSIGNMENT), insns, IntList.makeImmutable(label), label);
    addBlock(bb, IntList.EMPTY);
    if (synch) {
        RegisterSpec synchReg = getSynchReg();
        Insn insn;
        if (isStatic()) {
            insn = new ThrowingCstInsn(Rops.CONST_OBJECT, pos, RegisterSpecList.EMPTY, StdTypeList.EMPTY, method.getDefiningClass());
            insns = new InsnList(1);
            insns.set(0, insn);
        } else {
            insns = new InsnList(2);
            insn = new PlainCstInsn(Rops.MOVE_PARAM_OBJECT, pos, synchReg, RegisterSpecList.EMPTY, CstInteger.VALUE_0);
            insns.set(0, insn);
            insns.set(1, new PlainInsn(Rops.GOTO, pos, null, RegisterSpecList.EMPTY));
        }
        int label2 = getSpecialLabel(SYNCH_SETUP_2);
        insns.setImmutable();
        bb = new BasicBlock(label, insns, IntList.makeImmutable(label2), label2);
        addBlock(bb, IntList.EMPTY);
        insns = new InsnList(isStatic() ? 2 : 1);
        if (isStatic()) {
            insns.set(0, new PlainInsn(Rops.opMoveResultPseudo(synchReg), pos, synchReg, RegisterSpecList.EMPTY));
        }
        insn = new ThrowingInsn(Rops.MONITOR_ENTER, pos, RegisterSpecList.make(synchReg), StdTypeList.EMPTY);
        insns.set(isStatic() ? 1 : 0, insn);
        insns.setImmutable();
        bb = new BasicBlock(label2, insns, IntList.makeImmutable(0), 0);
        addBlock(bb, IntList.EMPTY);
    }
}

Example 15 with BasicBlock

use of com.android.dx.rop.code.BasicBlock in project J2ME-Loader by nikita36078.

the class Ropper method addExceptionSetupBlocks.

/**
 * Creates the exception handler setup blocks. "maxLocals"
 * below is because that's the register number corresponding
 * to the sole element on a one-deep stack (which is the
 * situation at the start of an exception handler block).
 */
private void addExceptionSetupBlocks() {
    int len = catchInfos.length;
    for (int i = 0; i < len; i++) {
        CatchInfo catches = catchInfos[i];
        if (catches != null) {
            for (ExceptionHandlerSetup one : catches.getSetups()) {
                Insn proto = labelToBlock(i).getFirstInsn();
                SourcePosition pos = proto.getPosition();
                InsnList il = new InsnList(2);
                Insn insn = new PlainInsn(Rops.opMoveException(one.getCaughtType()), pos, RegisterSpec.make(maxLocals, one.getCaughtType()), RegisterSpecList.EMPTY);
                il.set(0, insn);
                insn = new PlainInsn(Rops.GOTO, pos, null, RegisterSpecList.EMPTY);
                il.set(1, insn);
                il.setImmutable();
                BasicBlock bb = new BasicBlock(one.getLabel(), il, IntList.makeImmutable(i), i);
                addBlock(bb, startFrames[i].getSubroutines());
            }
        }
    }
}