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31 #ifndef __CPU_O3_SAT_COUNTER_HH__
32 #define __CPU_O3_SAT_COUNTER_HH__
34 #include "base/misc.hh"
35 #include "sim/host.hh"
38 * Private counter class for the internal saturating counters.
39 * Implements an n bit saturating counter and provides methods to
40 * increment, decrement, and read it.
41 * @todo Consider making this something that more closely mimics a
42 * built in class so you can use ++ or --.
48 * Constructor for the counter.
51 : initialVal(0), counter(0)
55 * Constructor for the counter.
56 * @param bits How many bits the counter will have.
58 SatCounter(unsigned bits)
59 : initialVal(0), maxVal((1 << bits) - 1), counter(0)
63 * Constructor for the counter.
64 * @param bits How many bits the counter will have.
65 * @param initial_val Starting value for each counter.
67 SatCounter(unsigned bits, uint8_t initial_val)
68 : initialVal(initialVal), maxVal((1 << bits) - 1), counter(initial_val)
70 // Check to make sure initial value doesn't exceed the max
72 if (initial_val > maxVal) {
73 fatal("BP: Initial counter value exceeds max size.");
78 * Sets the number of bits.
80 void setBits(unsigned bits) { maxVal = (1 << bits) - 1; }
82 void reset() { counter = initialVal; }
85 * Increments the counter's current value.
89 if (counter < maxVal) {
95 * Decrements the counter's current value.
105 * Read the counter's value.
107 const uint8_t read() const
116 #endif // __CPU_O3_SAT_COUNTER_HH__