Java 类org.apache.bcel.generic.LSTORE 实例源码

void removeUnusedLocals(Method mOrig, MethodGen m) {
    InstructionList il = m.getInstructionList();
    InstructionHandle[] ins = il.getInstructionHandles();
    for (int i = 0; i < ins.length; i++) {
        Instruction in = ins[i].getInstruction();

        if (in instanceof LocalVariableInstruction) {
            LocalVariableInstruction curr = (LocalVariableInstruction) in;
            if (mtab.getLocal(m, curr, ins[i].getPosition()) != null
                && curr.getIndex() < m.getMaxLocals() - 5
                && !mtab.isLocalUsedInInlet(mOrig, curr.getIndex())) {
                if (curr instanceof IINC) {
                    ins[i].setInstruction(new NOP());
                } else if (curr instanceof LSTORE || curr instanceof DSTORE) {
                    ins[i].setInstruction(new POP2());
                } else if (curr instanceof StoreInstruction) {
                    ins[i].setInstruction(new POP());
                } else if (curr instanceof ALOAD) {
                    ins[i].setInstruction(new ACONST_NULL());
                } else if (curr instanceof FLOAD) {
                    ins[i].setInstruction(new FCONST((float) 0.0));
                } else if (curr instanceof ILOAD) {
                    ins[i].setInstruction(new ICONST(0));
                } else if (curr instanceof DLOAD) {
                    ins[i].setInstruction(new DCONST(0.0));
                } else if (curr instanceof LLOAD) {
                    ins[i].setInstruction(new LCONST(0L));
                } else {
                    System.out.println("unhandled ins in "
                        + "removeUnusedLocals: " + curr);
                    System.exit(1);
                }
            }
        }
    }
}

@SuppressWarnings("unused")
// Called using reflection
private Instruction createInstructionLstore(Element inst) throws IllegalXMLVMException {
    // BCEL's LSTORE creation instruction only takes an integer!!!
    int idx = Integer.parseInt(inst.getAttributeValue("index"));
    return new LSTORE(idx);
}

/** Checks if the constraints of operands of the said instruction(s) are satisfied. */
public void visitLSTORE(LSTORE o){
    int idx = o.getIndex();
    if (idx < 0){
        constraintViolated(o, "Index '"+idx+"' must be non-negative. [Constraint by JustIce as an analogon to the single-slot xLOAD/xSTORE instructions; may not happen anyway.]");
    }
    else{
        int maxminus2 =  max_locals()-2;
        if (idx > maxminus2){
            constraintViolated(o, "Index '"+idx+"' must not be greater than max_locals-2 '"+maxminus2+"'.");
        }
    }
}

void initSpawnTargets(InstructionList il) {
    for (int i = 0; i < idTable.size(); i++) {
        InstructionList storeIns = getStoreIns(i);

        if (storeIns == null) {
            continue;
        }

        if (isArrayStore(storeIns.getStart())) {
            continue;
        }

        Instruction store = storeIns.getStart().getInstruction();

        if (store instanceof LSTORE) {
            il.insert(new LCONST(0));
            il.append(il.getStart(), store);
        } else if (store instanceof ISTORE) {
            il.insert(new ICONST(0));
            il.append(il.getStart(), store);
        } else if (store instanceof FSTORE) {
            il.insert(new FCONST((float) 0.0));
            il.append(il.getStart(), store);
        } else if (store instanceof DSTORE) {
            il.insert(new DCONST(0.0));
            il.append(il.getStart(), store);
        } else if (store instanceof ASTORE) {
            il.insert(new ACONST_NULL());
            il.append(il.getStart(), store);
        } else if (store instanceof PUTFIELD) {
            // no need to init.
        } else if (store instanceof PUTSTATIC) {
            // no need to init.
        } else if (store instanceof ALOAD) {
            // no need to init.
        } else {
            System.err.println("WARNING: Unhandled store instruction in "
                + "initSpawnTargets, opcode = " + store.getOpcode()
                + " ins = " + store);
            // System.exit(1);
        }
    }
}