static long multiplyHighAndShift(long x, long y, int shift) {
        long H = MULTIPLY_HIGH.multiplyHigh(x, y);
        if (shift >= 64) {
            int sr = shift - 64;
            return H >>> sr;
        }
        long L = x * y;
        return H << (64 - shift) | (L >>> shift);
    }
multiplyOutput

@param x > 0
@param y > 0
@param shift > 0
@return
core/src/main/java/com/alibaba/fastjson2/util/NumberUtils.java