Examples with ExceptionHandler jadx.core.dex.trycatch.ExceptionHandler used on opensource projects

Example 1 with ExceptionHandler

use of jadx.core.dex.trycatch.ExceptionHandler in project jadx by skylot.

the class ProcessTryCatchRegions method searchTryCatchDominators.

private static void searchTryCatchDominators(MethodNode mth, Map<BlockNode, TryCatchBlock> tryBlocksMap) {
    Set<TryCatchBlock> tryBlocks = new HashSet<TryCatchBlock>();
    // collect all try/catch blocks
    for (BlockNode block : mth.getBasicBlocks()) {
        CatchAttr c = block.get(AType.CATCH_BLOCK);
        if (c != null) {
            tryBlocks.add(c.getTryBlock());
        }
    }
    // for each try block search nearest dominator block
    for (TryCatchBlock tb : tryBlocks) {
        if (tb.getHandlersCount() == 0) {
            LOG.warn("No exception handlers in catch block, method: {}", mth);
            continue;
        }
        BitSet bs = new BitSet(mth.getBasicBlocks().size());
        for (ExceptionHandler excHandler : tb.getHandlers()) {
            SplitterBlockAttr splitter = excHandler.getHandlerBlock().get(AType.SPLITTER_BLOCK);
            if (splitter != null) {
                BlockNode block = splitter.getBlock();
                bs.set(block.getId());
            }
        }
        List<BlockNode> domBlocks = BlockUtils.bitSetToBlocks(mth, bs);
        BlockNode domBlock;
        if (domBlocks.size() != 1) {
            domBlock = BlockUtils.getTopBlock(domBlocks);
            if (domBlock == null) {
                throw new JadxRuntimeException("Exception block dominator not found, method:" + mth + ". bs: " + domBlocks);
            }
        } else {
            domBlock = domBlocks.get(0);
        }
        TryCatchBlock prevTB = tryBlocksMap.put(domBlock, tb);
        if (prevTB != null) {
            ErrorsCounter.methodError(mth, "Failed to process nested try/catch");
        }
    }
}

Example 2 with ExceptionHandler

use of jadx.core.dex.trycatch.ExceptionHandler in project jadx by skylot.

the class RegionMaker method processTryCatchBlocks.

public IRegion processTryCatchBlocks(MethodNode mth) {
    Set<TryCatchBlock> tcs = new HashSet<TryCatchBlock>();
    for (ExceptionHandler handler : mth.getExceptionHandlers()) {
        tcs.add(handler.getTryBlock());
    }
    for (TryCatchBlock tc : tcs) {
        List<BlockNode> blocks = new ArrayList<BlockNode>(tc.getHandlersCount());
        Set<BlockNode> splitters = new HashSet<BlockNode>();
        for (ExceptionHandler handler : tc.getHandlers()) {
            BlockNode handlerBlock = handler.getHandlerBlock();
            if (handlerBlock != null) {
                blocks.add(handlerBlock);
                splitters.addAll(handlerBlock.getPredecessors());
            } else {
                LOG.debug(ErrorsCounter.formatErrorMsg(mth, "No exception handler block: " + handler));
            }
        }
        Set<BlockNode> exits = new HashSet<BlockNode>();
        for (BlockNode splitter : splitters) {
            for (BlockNode handler : blocks) {
                List<BlockNode> s = splitter.getSuccessors();
                if (s.isEmpty()) {
                    LOG.debug(ErrorsCounter.formatErrorMsg(mth, "No successors for splitter: " + splitter));
                    continue;
                }
                BlockNode ss = s.get(0);
                BlockNode cross = BlockUtils.getPathCross(mth, ss, handler);
                if (cross != null && cross != ss && cross != handler) {
                    exits.add(cross);
                }
            }
        }
        for (ExceptionHandler handler : tc.getHandlers()) {
            processExcHandler(handler, exits);
        }
    }
    return processHandlersOutBlocks(mth, tcs);
}

Example 3 with ExceptionHandler

use of jadx.core.dex.trycatch.ExceptionHandler in project jadx by skylot.

the class BlockExceptionHandler method markExceptionHandlers.

/**
	 * Set exception handler attribute for whole block
	 */
private static void markExceptionHandlers(BlockNode block) {
    if (block.getInstructions().isEmpty()) {
        return;
    }
    InsnNode me = block.getInstructions().get(0);
    ExcHandlerAttr handlerAttr = me.get(AType.EXC_HANDLER);
    if (handlerAttr == null || me.getType() != InsnType.MOVE_EXCEPTION) {
        return;
    }
    ExceptionHandler excHandler = handlerAttr.getHandler();
    block.addAttr(handlerAttr);
    // set correct type for 'move-exception' operation
    ArgType type = excHandler.isCatchAll() ? ArgType.THROWABLE : excHandler.getCatchType().getType();
    RegisterArg resArg = me.getResult();
    resArg = InsnArg.reg(resArg.getRegNum(), type);
    me.setResult(resArg);
    me.add(AFlag.DONT_INLINE);
    excHandler.setArg(resArg);
}

Example 4 with ExceptionHandler

use of jadx.core.dex.trycatch.ExceptionHandler in project jadx by skylot.

the class ModVisitor method processMoveException.

private static void processMoveException(MethodNode mth, BlockNode block, InsnNode insn, InstructionRemover remover) {
    ExcHandlerAttr excHandlerAttr = block.get(AType.EXC_HANDLER);
    if (excHandlerAttr == null) {
        return;
    }
    ExceptionHandler excHandler = excHandlerAttr.getHandler();
    // result arg used both in this insn and exception handler,
    RegisterArg resArg = insn.getResult();
    ArgType type = excHandler.isCatchAll() ? ArgType.THROWABLE : excHandler.getCatchType().getType();
    String name = excHandler.isCatchAll() ? "th" : "e";
    if (resArg.getName() == null) {
        resArg.setName(name);
    }
    SSAVar sVar = insn.getResult().getSVar();
    if (sVar.getUseCount() == 0) {
        excHandler.setArg(new NamedArg(name, type));
        remover.add(insn);
    } else if (sVar.isUsedInPhi()) {
        // exception var moved to external variable => replace with 'move' insn
        InsnNode moveInsn = new InsnNode(InsnType.MOVE, 1);
        moveInsn.setResult(insn.getResult());
        NamedArg namedArg = new NamedArg(name, type);
        moveInsn.addArg(namedArg);
        excHandler.setArg(namedArg);
        replaceInsn(block, 0, moveInsn);
    }
}

Example 5 with ExceptionHandler

use of jadx.core.dex.trycatch.ExceptionHandler in project jadx by skylot.

the class BlockFinallyExtract method extractFinally.

/**
	 * Search and remove common code from 'catch' and 'handlers'.
	 */
private static boolean extractFinally(MethodNode mth, ExceptionHandler handler) {
    int count = handler.getBlocks().size();
    BitSet bs = new BitSet(count);
    List<BlockNode> blocks = new ArrayList<BlockNode>(count);
    for (BlockNode block : handler.getBlocks()) {
        List<InsnNode> insns = block.getInstructions();
        if (!insns.isEmpty()) {
            if (insns.get(0).getType() != InsnType.MOVE_EXCEPTION) {
                blocks.add(block);
            }
            bs.set(block.getId());
        }
    }
    if (blocks.isEmpty()) {
        // nothing to do
        return false;
    }
    List<BlocksRemoveInfo> removes = new LinkedList<BlocksRemoveInfo>();
    Set<BlockNode> splitters = new HashSet<BlockNode>();
    // remove 'finally' from handlers
    TryCatchBlock tryBlock = handler.getTryBlock();
    if (tryBlock.getHandlersCount() > 1) {
        for (ExceptionHandler otherHandler : tryBlock.getHandlers()) {
            if (otherHandler == handler) {
                continue;
            }
            for (BlockNode hb : otherHandler.getBlocks()) {
                BlocksRemoveInfo removeInfo = removeInsns(mth, hb, blocks, bs);
                if (removeInfo != null) {
                    removes.add(removeInfo);
                    break;
                }
            }
        }
        if (removes.size() != tryBlock.getHandlersCount() - 1) {
            return false;
        }
    }
    for (ExceptionHandler otherHandler : tryBlock.getHandlers()) {
        SplitterBlockAttr splitterAttr = otherHandler.getHandlerBlock().get(AType.SPLITTER_BLOCK);
        if (splitterAttr != null) {
            BlockNode splBlock = splitterAttr.getBlock();
            if (!splBlock.getCleanSuccessors().isEmpty()) {
                splitters.add(splBlock);
            }
        }
    }
    // remove 'finally' from 'try' blocks (dominated by splitter block)
    boolean removed = false;
    for (BlockNode splitter : splitters) {
        BlockNode start = splitter.getCleanSuccessors().get(0);
        List<BlockNode> list = BlockUtils.collectBlocksDominatedBy(splitter, start);
        for (BlockNode block : list) {
            if (bs.get(block.getId())) {
                continue;
            }
            BlocksRemoveInfo removeInfo = removeInsns(mth, block, blocks, bs);
            if (removeInfo != null) {
                removes.add(removeInfo);
                removed = true;
                break;
            }
        }
    }
    if (!removed) {
        return false;
    }
    // 'finally' extract confirmed, run remove steps
    LiveVarAnalysis laBefore = null;
    boolean runReMap = isReMapNeeded(removes);
    if (runReMap) {
        laBefore = new LiveVarAnalysis(mth);
        laBefore.runAnalysis();
    }
    for (BlocksRemoveInfo removeInfo : removes) {
        if (!applyRemove(mth, removeInfo)) {
            return false;
        }
    }
    LiveVarAnalysis laAfter = null;
    // remove 'move-exception' instruction
    BlockNode handlerBlock = handler.getHandlerBlock();
    InsnNode me = BlockUtils.getLastInsn(handlerBlock);
    if (me != null && me.getType() == InsnType.MOVE_EXCEPTION) {
        boolean replaced = false;
        List<InsnNode> insnsList = handlerBlock.getInstructions();
        if (!handlerBlock.getCleanSuccessors().isEmpty()) {
            laAfter = new LiveVarAnalysis(mth);
            laAfter.runAnalysis();
            RegisterArg resArg = me.getResult();
            BlockNode succ = handlerBlock.getCleanSuccessors().get(0);
            if (laAfter.isLive(succ, resArg.getRegNum())) {
                // kill variable
                InsnNode kill = new InsnNode(InsnType.NOP, 0);
                kill.setResult(resArg);
                kill.add(AFlag.REMOVE);
                insnsList.set(insnsList.size() - 1, kill);
                replaced = true;
            }
        }
        if (!replaced) {
            insnsList.remove(insnsList.size() - 1);
            handlerBlock.add(AFlag.SKIP);
        }
    }
    // generate 'move' instruction for mapped register pairs
    if (runReMap) {
        if (laAfter == null) {
            laAfter = new LiveVarAnalysis(mth);
            laAfter.runAnalysis();
        }
        performVariablesReMap(mth, removes, laBefore, laAfter);
    }
    handler.setFinally(true);
    return true;
}