| //===- unittests/Support/BlockFrequencyTest.cpp - BlockFrequency tests ----===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/Support/BlockFrequency.h" |
| #include "llvm/Support/BranchProbability.h" |
| #include "llvm/Support/DataTypes.h" |
| #include "gtest/gtest.h" |
| #include <climits> |
| |
| using namespace llvm; |
| |
| namespace { |
| |
| TEST(BlockFrequencyTest, OneToZero) { |
| BlockFrequency Freq(1); |
| BranchProbability Prob(UINT32_MAX / 3, UINT32_MAX); |
| Freq *= Prob; |
| EXPECT_EQ(Freq.getFrequency(), 0u); |
| |
| Freq = BlockFrequency(1); |
| 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); |
| |
| Freq = BlockFrequency(1); |
| Freq *= Prob; |
| EXPECT_EQ(Freq.getFrequency(), 1u); |
| } |
| |
| TEST(BlockFrequencyTest, ThreeToOne) { |
| BlockFrequency Freq(3); |
| BranchProbability Prob(3000000, 9000000); |
| Freq *= Prob; |
| EXPECT_EQ(Freq.getFrequency(), 1u); |
| |
| Freq = BlockFrequency(3); |
| 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(), 9223372036854775807ULL); |
| |
| Freq = BlockFrequency(UINT64_MAX); |
| Freq *= Prob; |
| EXPECT_EQ(Freq.getFrequency(), 9223372036854775807ULL); |
| } |
| |
| 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); |
| |
| Freq = BlockFrequency(Big); |
| 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); |
| |
| // This additionally makes sure if we have a value equal to our saturating |
| // value, we do not signal saturation if the result equals said value, but |
| // saturating does not occur. |
| Freq = BlockFrequency(UINT64_MAX); |
| Freq *= Prob; |
| 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); |
| EXPECT_EQ(Freq.getFrequency(), 0x6666666666666666ULL); |
| } |
| |
| TEST(BlockFrequencyTest, Saturate) { |
| BlockFrequency Freq(0x3333333333333333ULL); |
| Freq /= BranchProbability(100, 300); |
| EXPECT_EQ(Freq.getFrequency(), 0x9999999866666668ULL); |
| Freq /= BranchProbability(1, 2); |
| EXPECT_EQ(Freq.getFrequency(), UINT64_MAX); |
| |
| Freq = 0x1000000000000000ULL; |
| Freq /= BranchProbability(10000, 170000); |
| EXPECT_EQ(Freq.getFrequency(), UINT64_MAX); |
| |
| // Try to cheat the multiplication overflow check. |
| Freq = 0x00000001f0000001ull; |
| Freq /= BranchProbability(1000, 0xf000000f); |
| EXPECT_EQ(33527736066704712ULL, Freq.getFrequency()); |
| } |
| |
| TEST(BlockFrequencyTest, SaturatingRightShift) { |
| BlockFrequency Freq(0x10080ULL); |
| Freq >>= 2; |
| EXPECT_EQ(Freq.getFrequency(), 0x4020ULL); |
| Freq >>= 20; |
| EXPECT_EQ(Freq.getFrequency(), 0x1ULL); |
| } |
| |
| } |