unittests/Support/BlockFrequencyTest.cpp

#include "llvm/Support/DataTypes.h"
#include "llvm/Support/BlockFrequency.h"
#include "llvm/Support/BranchProbability.h"

#include "gtest/gtest.h"
#include <climits>

using namespace llvm;

namespace {

TEST(BlockFrequencyTest, OneToZero) {
  BlockFrequency Freq(1);
  BranchProbability Prob(UINT32_MAX - 1, UINT32_MAX);
  Freq *= Prob;
  EXPECT_EQ(Freq.getFrequency(), 0u);
}

TEST(BlockFrequencyTest, OneToOne) {
  BlockFrequency Freq(1);
  BranchProbability Prob(UINT32_MAX, UINT32_MAX);
  Freq *= Prob;
  EXPECT_EQ(Freq.getFrequency(), 1u);
}

TEST(BlockFrequencyTest, ThreeToOne) {
  BlockFrequency Freq(3);
  BranchProbability Prob(3000000, 9000000);
  Freq *= Prob;
  EXPECT_EQ(Freq.getFrequency(), 1u);
}

TEST(BlockFrequencyTest, MaxToHalfMax) {
  BlockFrequency Freq(UINT64_MAX);
  BranchProbability Prob(UINT32_MAX / 2, UINT32_MAX);
  Freq *= Prob;
  EXPECT_EQ(Freq.getFrequency(), 9223372034707292159LLu);
}

TEST(BlockFrequencyTest, BigToBig) {
  const uint64_t Big = 387246523487234346LL;
  const uint32_t P = 123456789;
  BlockFrequency Freq(Big);
  BranchProbability Prob(P, P);
  Freq *= Prob;
  EXPECT_EQ(Freq.getFrequency(), Big);
}

TEST(BlockFrequencyTest, MaxToMax) {
  BlockFrequency Freq(UINT64_MAX);
  BranchProbability Prob(UINT32_MAX, UINT32_MAX);
  Freq *= Prob;
  EXPECT_EQ(Freq.getFrequency(), UINT64_MAX);
}

}