1 #include "llvm/Support/BlockFrequency.h"
2 #include "llvm/Support/BranchProbability.h"
3 #include "llvm/Support/DataTypes.h"
4 #include "gtest/gtest.h"
5 #include <climits>
6
7 using namespace llvm;
8
9 namespace {
10
TEST(BlockFrequencyTest,OneToZero)11 TEST(BlockFrequencyTest, OneToZero) {
12 BlockFrequency Freq(1);
13 BranchProbability Prob(UINT32_MAX - 1, UINT32_MAX);
14 Freq *= Prob;
15 EXPECT_EQ(Freq.getFrequency(), 0u);
16
17 Freq = BlockFrequency(1);
18 Freq *= Prob;
19 EXPECT_EQ(Freq.getFrequency(), 0u);
20 }
21
TEST(BlockFrequencyTest,OneToOne)22 TEST(BlockFrequencyTest, OneToOne) {
23 BlockFrequency Freq(1);
24 BranchProbability Prob(UINT32_MAX, UINT32_MAX);
25 Freq *= Prob;
26 EXPECT_EQ(Freq.getFrequency(), 1u);
27
28 Freq = BlockFrequency(1);
29 Freq *= Prob;
30 EXPECT_EQ(Freq.getFrequency(), 1u);
31 }
32
TEST(BlockFrequencyTest,ThreeToOne)33 TEST(BlockFrequencyTest, ThreeToOne) {
34 BlockFrequency Freq(3);
35 BranchProbability Prob(3000000, 9000000);
36 Freq *= Prob;
37 EXPECT_EQ(Freq.getFrequency(), 1u);
38
39 Freq = BlockFrequency(3);
40 Freq *= Prob;
41 EXPECT_EQ(Freq.getFrequency(), 1u);
42 }
43
TEST(BlockFrequencyTest,MaxToHalfMax)44 TEST(BlockFrequencyTest, MaxToHalfMax) {
45 BlockFrequency Freq(UINT64_MAX);
46 BranchProbability Prob(UINT32_MAX / 2, UINT32_MAX);
47 Freq *= Prob;
48 EXPECT_EQ(Freq.getFrequency(), 9223372034707292159ULL);
49
50 Freq = BlockFrequency(UINT64_MAX);
51 Freq *= Prob;
52 EXPECT_EQ(Freq.getFrequency(), 9223372034707292159ULL);
53 }
54
TEST(BlockFrequencyTest,BigToBig)55 TEST(BlockFrequencyTest, BigToBig) {
56 const uint64_t Big = 387246523487234346LL;
57 const uint32_t P = 123456789;
58 BlockFrequency Freq(Big);
59 BranchProbability Prob(P, P);
60 Freq *= Prob;
61 EXPECT_EQ(Freq.getFrequency(), Big);
62
63 Freq = BlockFrequency(Big);
64 Freq *= Prob;
65 EXPECT_EQ(Freq.getFrequency(), Big);
66 }
67
TEST(BlockFrequencyTest,MaxToMax)68 TEST(BlockFrequencyTest, MaxToMax) {
69 BlockFrequency Freq(UINT64_MAX);
70 BranchProbability Prob(UINT32_MAX, UINT32_MAX);
71 Freq *= Prob;
72 EXPECT_EQ(Freq.getFrequency(), UINT64_MAX);
73
74 // This additionally makes sure if we have a value equal to our saturating
75 // value, we do not signal saturation if the result equals said value, but
76 // saturating does not occur.
77 Freq = BlockFrequency(UINT64_MAX);
78 Freq *= Prob;
79 EXPECT_EQ(Freq.getFrequency(), UINT64_MAX);
80 }
81
TEST(BlockFrequency,Divide)82 TEST(BlockFrequency, Divide) {
83 BlockFrequency Freq(0x3333333333333333ULL);
84 Freq /= BranchProbability(1, 2);
85 EXPECT_EQ(Freq.getFrequency(), 0x6666666666666666ULL);
86 }
87
TEST(BlockFrequencyTest,Saturate)88 TEST(BlockFrequencyTest, Saturate) {
89 BlockFrequency Freq(0x3333333333333333ULL);
90 Freq /= BranchProbability(100, 300);
91 EXPECT_EQ(Freq.getFrequency(), 0x9999999999999999ULL);
92 Freq /= BranchProbability(1, 2);
93 EXPECT_EQ(Freq.getFrequency(), UINT64_MAX);
94
95 Freq = 0x1000000000000000ULL;
96 Freq /= BranchProbability(10000, 160000);
97 EXPECT_EQ(Freq.getFrequency(), UINT64_MAX);
98
99 // Try to cheat the multiplication overflow check.
100 Freq = 0x00000001f0000001ull;
101 Freq /= BranchProbability(1000, 0xf000000f);
102 EXPECT_EQ(33506781356485509ULL, Freq.getFrequency());
103 }
104
TEST(BlockFrequencyTest,SaturatingRightShift)105 TEST(BlockFrequencyTest, SaturatingRightShift) {
106 BlockFrequency Freq(0x10080ULL);
107 Freq >>= 2;
108 EXPECT_EQ(Freq.getFrequency(), 0x4020ULL);
109 Freq >>= 20;
110 EXPECT_EQ(Freq.getFrequency(), 0x1ULL);
111 }
112
113 }
114