BlockFrequency &operator+=(BlockFrequency Freq);
BlockFrequency operator+(BlockFrequency Freq) const;
+ /// \brief Subtracts another block frequency using saturating arithmetic.
+ BlockFrequency &operator-=(BlockFrequency Freq);
+ BlockFrequency operator-(BlockFrequency Freq) const;
+
/// \brief Shift block frequency to the right by count digits saturating to 1.
BlockFrequency &operator>>=(const unsigned count);
return NewFreq;
}
+BlockFrequency &BlockFrequency::operator-=(BlockFrequency Freq) {
+ // If underflow, set frequency to 0.
+ if (Frequency <= Freq.Frequency)
+ Frequency = 0;
+ else
+ Frequency -= Freq.Frequency;
+ return *this;
+}
+
+BlockFrequency BlockFrequency::operator-(BlockFrequency Freq) const {
+ BlockFrequency NewFreq(Frequency);
+ NewFreq -= Freq;
+ return NewFreq;
+}
+
BlockFrequency &BlockFrequency::operator>>=(const unsigned count) {
// Frequency can never be 0 by design.
assert(Frequency != 0);
EXPECT_EQ(Freq.getFrequency(), UINT64_MAX);
}
+TEST(BlockFrequencyTest, Subtract) {
+ BlockFrequency Freq1(0), Freq2(1);
+ EXPECT_EQ((Freq1 - Freq2).getFrequency(), 0u);
+ EXPECT_EQ((Freq2 - Freq1).getFrequency(), 1u);
+}
+
TEST(BlockFrequency, Divide) {
BlockFrequency Freq(0x3333333333333333ULL);
Freq /= BranchProbability(1, 2);