import jdk.internal.org.objectweb.asm.tree.LabelNode; //导入依赖的package包/类
/**
 * Walks the method and determines which internal subroutine(s), if any,
 * each instruction is a method of.
 */
private void markSubroutines() {
    BitSet anyvisited = new BitSet();

    // First walk the main subroutine and find all those instructions which
    // can be reached without invoking any JSR at all
    markSubroutineWalk(mainSubroutine, 0, anyvisited);

    // Go through the head of each subroutine and find any nodes reachable
    // to that subroutine without following any JSR links.
    for (Iterator<Map.Entry<LabelNode, BitSet>> it = subroutineHeads
            .entrySet().iterator(); it.hasNext();) {
        Map.Entry<LabelNode, BitSet> entry = it.next();
        LabelNode lab = entry.getKey();
        BitSet sub = entry.getValue();
        int index = instructions.indexOf(lab);
        markSubroutineWalk(sub, index, anyvisited);
    }
}
 

import jdk.internal.org.objectweb.asm.tree.LabelNode; //导入依赖的package包/类
/**
 * Walks the method and determines which internal subroutine(s), if any,
 * each instruction is a method of.
 */
private void markSubroutines() {
    BitSet anyvisited = new BitSet();

    // First walk the main subroutine and find all those instructions which
    // can be reached without invoking any JSR at all
    markSubroutineWalk(mainSubroutine, 0, anyvisited);

    // Go through the head of each subroutine and find any nodes reachable
    // to that subroutine without following any JSR links.
    for (Iterator<Map.Entry<LabelNode,BitSet>> it = subroutineHeads.entrySet().iterator(); it.hasNext();)
    {
        Map.Entry<LabelNode,BitSet> entry = it.next();
        LabelNode lab = entry.getKey();
        BitSet sub = entry.getValue();
        int index = instructions.indexOf(lab);
        markSubroutineWalk(sub, index, anyvisited);
    }
}
 

import jdk.internal.org.objectweb.asm.tree.LabelNode; //导入依赖的package包/类
/**
 * Detects a JSR instruction and sets a flag to indicate we will need to do
 * inlining.
 */
@Override
public void visitJumpInsn(final int opcode, final Label lbl) {
    super.visitJumpInsn(opcode, lbl);
    LabelNode ln = ((JumpInsnNode) instructions.getLast()).label;
    if (opcode == JSR && !subroutineHeads.containsKey(ln)) {
        subroutineHeads.put(ln, new BitSet());
    }
}
 

import jdk.internal.org.objectweb.asm.tree.LabelNode; //导入依赖的package包/类
Subroutine(final LabelNode start, final int maxLocals,
        final JumpInsnNode caller) {
    this.start = start;
    this.access = new boolean[maxLocals];
    this.callers = new ArrayList<JumpInsnNode>();
    callers.add(caller);
}
 

import jdk.internal.org.objectweb.asm.tree.LabelNode; //导入依赖的package包/类
Subroutine(
    final LabelNode start,
    final int maxLocals,
    final JumpInsnNode caller)
{
    this.start = start;
    this.access = new boolean[maxLocals];
    this.callers = new ArrayList<JumpInsnNode>();
    callers.add(caller);
}
 

import jdk.internal.org.objectweb.asm.tree.LabelNode; //导入依赖的package包/类
@Override
public Set<Map.Entry<LabelNode, LabelNode>> entrySet() {
    return null;
}
 

import jdk.internal.org.objectweb.asm.tree.LabelNode; //导入依赖的package包/类
@Override
public LabelNode get(final Object o) {
    return gotoLabel((LabelNode) o);
}