private static void renameVar(MethodNode mth, SSAVar[] vars, int[] vers, BlockNode block) { SSAVar[] inputVars = Arrays.copyOf(vars, vars.length); for (InsnNode insn : block.getInstructions()) { if (insn.getType() != InsnType.PHI) { for (InsnArg arg : insn.getArguments()) { if (!arg.isRegister()) { continue; } RegisterArg reg = (RegisterArg) arg; int regNum = reg.getRegNum(); SSAVar var = vars[regNum]; if (var == null) { throw new JadxRuntimeException( "Not initialized variable reg: " + regNum + ", insn: " + insn + ", block:" + block + ", method: " + mth); } var.use(reg); } } RegisterArg result = insn.getResult(); if (result != null) { int regNum = result.getRegNum(); vars[regNum] = mth.makeNewSVar(regNum, vers, result); } } for (BlockNode s : block.getSuccessors()) { PhiListAttr phiList = s.get(AType.PHI_LIST); if (phiList == null) { continue; } int j = s.getPredecessors().indexOf(block); if (j == -1) { throw new JadxRuntimeException("Can't find predecessor for " + block + " " + s); } for (PhiInsn phiInsn : phiList.getList()) { if (j >= phiInsn.getArgsCount()) { continue; } int regNum = phiInsn.getResult().getRegNum(); SSAVar var = vars[regNum]; if (var == null) { continue; } var.use(phiInsn.getArg(j)); var.setUsedInPhi(phiInsn); } } for (BlockNode domOn : block.getDominatesOn()) { renameVar(mth, vars, vers, domOn); } System.arraycopy(inputVars, 0, vars, 0, vars.length); }
private static void removePhiWithSameArgs(PhiInsn phi, List<PhiInsn> insnToRemove) { if (phi.getArgsCount() <= 1) { insnToRemove.add(phi); return; } boolean allSame = true; SSAVar var = phi.getArg(0).getSVar(); for (int i = 1; i < phi.getArgsCount(); i++) { if (var != phi.getArg(i).getSVar()) { allSame = false; break; } } if (allSame) { // replace insnToRemove.add(phi); SSAVar assign = phi.getResult().getSVar(); for (RegisterArg arg : new ArrayList<RegisterArg>(assign.getUseList())) { assign.removeUse(arg); var.use(arg); } } }
private static void fixLastTryCatchAssign(MethodNode mth) { for (BlockNode block : mth.getBasicBlocks()) { PhiListAttr phiList = block.get(AType.PHI_LIST); if (phiList == null || !block.contains(AType.EXC_HANDLER)) { continue; } for (PhiInsn phi : phiList.getList()) { for (int i = 0; i < phi.getArgsCount(); i++) { RegisterArg arg = phi.getArg(i); InsnNode parentInsn = arg.getAssignInsn(); if (parentInsn != null && parentInsn.getResult() != null && parentInsn.contains(AFlag.TRY_LEAVE)) { phi.removeArg(arg); } } } } }