cpu/beta_cpu/sat_counter.hh

   1 #ifndef __CPU_BETA_CPU_SAT_COUNTER_HH__
   2 #define __CPU_BETA_CPU_SAT_COUNTER_HH__
   3
   4 #include <stdint.h>
   5
   6 /**
   7  * Private counter class for the internal saturating counters.
   8  * Implements an n bit saturating counter and provides methods to
   9  * increment, decrement, and read it.
  10  * @todo Consider making this something that more closely mimics a
  11  * built in class so you can use ++ or --.
  12  */
  13 class SatCounter
  14 {
  15   public:
  16     /**
  17      * Constructor for the counter.
  18      */
  19     SatCounter();
  20
  21     /**
  22      * Constructor for the counter.
  23      * @param bits How many bits the counter will have.
  24      */
  25     SatCounter(unsigned bits);
  26
  27     /**
  28      * Constructor for the counter.
  29      * @param bits How many bits the counter will have.
  30      * @param initial_val Starting value for each counter.
  31      */
  32     SatCounter(unsigned bits, unsigned initial_val);
  33
  34     /**
  35      * Sets the number of bits.
  36      */
  37     void setBits(unsigned bits);
  38
  39     /**
  40      * Increments the counter's current value.
  41      */
  42     void increment();
  43
  44     /**
  45      * Decrements the counter's current value.
  46      */
  47     void decrement();
  48
  49     /**
  50      * Read the counter's value.
  51      */
  52     const uint8_t read() const
  53     {
  54         return counter;
  55     }
  56
  57   private:
  58     uint8_t maxVal;
  59     uint8_t counter;
  60 };
  61
  62 #endif // __CPU_BETA_CPU_SAT_COUNTER_HH__