Examples with BlockNode jadx.core.dex.nodes.BlockNode used on opensource projects

Example 11 with BlockNode

use of jadx.core.dex.nodes.BlockNode in project jadx by skylot.

the class BlockFinallyExtract method mergeReturns.

private static boolean mergeReturns(MethodNode mth, Set<BlocksPair> outs) {
    Set<BlockNode> rightOuts = new HashSet<BlockNode>();
    boolean allReturns = true;
    for (BlocksPair outPair : outs) {
        BlockNode first = outPair.getFirst();
        if (!first.isReturnBlock()) {
            allReturns = false;
        }
        rightOuts.add(outPair.getSecond());
    }
    if (!allReturns || rightOuts.size() != 1) {
        return false;
    }
    Iterator<BlocksPair> it = outs.iterator();
    while (it.hasNext()) {
        BlocksPair out = it.next();
        BlockNode returnBlock = out.getFirst();
        if (!returnBlock.contains(AFlag.ORIG_RETURN)) {
            markForRemove(mth, returnBlock);
            it.remove();
        }
    }
    return true;
}

Example 12 with BlockNode

use of jadx.core.dex.nodes.BlockNode in project jadx by skylot.

the class BlockFinish method visit.

@Override
public void visit(MethodNode mth) {
    if (mth.isNoCode()) {
        return;
    }
    for (BlockNode block : mth.getBasicBlocks()) {
        block.updateCleanSuccessors();
        initBlocksInIfNodes(block);
        fixSplitterBlock(block);
    }
    mth.finishBasicBlocks();
}

Example 13 with BlockNode

use of jadx.core.dex.nodes.BlockNode in project jadx by skylot.

the class ModVisitor method removeStep.

/**
	 * Remove unnecessary instructions
	 */
private static void removeStep(MethodNode mth, InstructionRemover remover) {
    for (BlockNode block : mth.getBasicBlocks()) {
        remover.setBlock(block);
        for (InsnNode insn : block.getInstructions()) {
            switch(insn.getType()) {
                case NOP:
                case GOTO:
                case NEW_INSTANCE:
                    remover.add(insn);
                    break;
                default:
                    break;
            }
        }
        remover.perform();
    }
}

Example 14 with BlockNode

use of jadx.core.dex.nodes.BlockNode in project jadx by skylot.

the class BlockProcessor method splitReturn.

/**
	 * Splice return block if several predecessors presents
	 */
private static boolean splitReturn(MethodNode mth) {
    if (mth.getExitBlocks().size() != 1) {
        return false;
    }
    BlockNode exitBlock = mth.getExitBlocks().get(0);
    if (exitBlock.getInstructions().size() != 1 || exitBlock.contains(AFlag.SYNTHETIC)) {
        return false;
    }
    List<BlockNode> preds = exitBlock.getPredecessors();
    if (preds.size() < 2) {
        return false;
    }
    preds = BlockUtils.filterPredecessors(exitBlock);
    if (preds.size() < 2) {
        return false;
    }
    InsnNode returnInsn = exitBlock.getInstructions().get(0);
    if (returnInsn.getArgsCount() != 0 && !isReturnArgAssignInPred(preds, returnInsn)) {
        return false;
    }
    boolean first = true;
    for (BlockNode pred : preds) {
        BlockNode newRetBlock = BlockSplitter.startNewBlock(mth, exitBlock.getStartOffset());
        newRetBlock.add(AFlag.SYNTHETIC);
        InsnNode newRetInsn;
        if (first) {
            newRetInsn = returnInsn;
            newRetBlock.add(AFlag.ORIG_RETURN);
            first = false;
        } else {
            newRetInsn = duplicateReturnInsn(returnInsn);
        }
        newRetBlock.getInstructions().add(newRetInsn);
        removeConnection(pred, exitBlock);
        connect(pred, newRetBlock);
    }
    cleanExitNodes(mth);
    return true;
}

Example 15 with BlockNode

use of jadx.core.dex.nodes.BlockNode in project jadx by skylot.

the class BlockProcessor method computeDominators.

private static void computeDominators(MethodNode mth) {
    List<BlockNode> basicBlocks = mth.getBasicBlocks();
    int nBlocks = basicBlocks.size();
    for (int i = 0; i < nBlocks; i++) {
        BlockNode block = basicBlocks.get(i);
        block.setId(i);
        block.setDoms(new BitSet(nBlocks));
        block.getDoms().set(0, nBlocks);
    }
    BlockNode entryBlock = mth.getEnterBlock();
    entryBlock.getDoms().clear();
    entryBlock.getDoms().set(entryBlock.getId());
    BitSet dset = new BitSet(nBlocks);
    boolean changed;
    do {
        changed = false;
        for (BlockNode block : basicBlocks) {
            if (block == entryBlock) {
                continue;
            }
            BitSet d = block.getDoms();
            if (!changed) {
                dset.clear();
                dset.or(d);
            }
            for (BlockNode pred : block.getPredecessors()) {
                d.and(pred.getDoms());
            }
            d.set(block.getId());
            if (!changed && !d.equals(dset)) {
                changed = true;
            }
        }
    } while (changed);
    markLoops(mth);
    // clear self dominance
    for (BlockNode block : basicBlocks) {
        block.getDoms().clear(block.getId());
    }
    // calculate immediate dominators
    for (BlockNode block : basicBlocks) {
        if (block == entryBlock) {
            continue;
        }
        BlockNode idom;
        List<BlockNode> preds = block.getPredecessors();
        if (preds.size() == 1) {
            idom = preds.get(0);
        } else {
            BitSet bs = new BitSet(block.getDoms().length());
            bs.or(block.getDoms());
            for (int i = bs.nextSetBit(0); i >= 0; i = bs.nextSetBit(i + 1)) {
                BlockNode dom = basicBlocks.get(i);
                bs.andNot(dom.getDoms());
            }
            if (bs.cardinality() != 1) {
                throw new JadxRuntimeException("Can't find immediate dominator for block " + block + " in " + bs + " preds:" + preds);
            }
            idom = basicBlocks.get(bs.nextSetBit(0));
        }
        block.setIDom(idom);
        idom.addDominatesOn(block);
    }
}