mask_counter.h

 
#ifndef BACKENDS_TOFINO_BF_ASM_MASK_COUNTER_H_
#define BACKENDS_TOFINO_BF_ASM_MASK_COUNTER_H_
 
#include <limits.h>
 
#include "lib/bitvec.h"
 
class MaskCounter {
    unsigned mask, val;
    bool oflo;
 
 public:
    explicit MaskCounter(unsigned m) : mask(m), val(0), oflo(false) {}
    explicit operator bool() const { return !oflo; }
    operator unsigned() const { return val; }
    bool operator==(const MaskCounter &a) const { return val == a.val && oflo == a.oflo; }
    MaskCounter &operator++() {
        val = ((val | ~mask) + 1) & mask;
        if (val == 0) oflo = true;
        return *this;
    }
    MaskCounter operator++(int) {
        MaskCounter tmp(*this);
        ++*this;
        return tmp;
    }
    MaskCounter &operator--() {
        val = (val - 1) & mask;
        if (val == mask) oflo = true;
        return *this;
    }
    MaskCounter operator--(int) {
        MaskCounter tmp(*this);
        --*this;
        return tmp;
    }
    MaskCounter &clear() {
        val = 0;
        oflo = false;
        return *this;
    }
    MaskCounter &overflow(bool v = true) {
        oflo = v;
        return *this;
    }
};
 
#endif /* BACKENDS_TOFINO_BF_ASM_MASK_COUNTER_H_ */