src/org/nutz/repo/org/objectweb/asm/Frame.java
private void pop(final int elements) {
        if (outputStackTop >= elements) {
            outputStackTop -= elements;
        } else {
            // if the number of elements to be popped is greater than the number
            // of elements in the output stack, clear it, and pops the remaining
            // elements from the input stack.
            owner.inputStackTop -= elements - outputStackTop;
            outputStackTop = 0;
        }
    }
private void pop(final int elements) {
        if (outputStackTop >= elements) {
            outputStackTop -= elements;
        } else {
            // if the number of elements to be popped is greater than the number
            // of elements in the output stack, clear it, and pops the remaining
            // elements from the input stack.
            owner.inputStackTop -= elements - outputStackTop;
            outputStackTop = 0;
        }
    }
Pops the given number of types from the output frame stack.

@param elements
the number of types that must be popped.