1 //===-- Benchmark Memory Test ---------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "LibcMemoryBenchmark.h"
10 #include "llvm/Support/Alignment.h"
11 #include "gmock/gmock.h"
12 #include "gtest/gtest.h"
13 
14 using testing::AllOf;
15 using testing::AnyOf;
16 using testing::ElementsAre;
17 using testing::Ge;
18 using testing::Gt;
19 using testing::Le;
20 using testing::Lt;
21 
22 namespace llvm {
23 namespace libc_benchmarks {
24 namespace {
25 
TEST(AlignedBuffer,IsAligned)26 TEST(AlignedBuffer, IsAligned) {
27   AlignedBuffer AB(0);
28   EXPECT_TRUE(isAddrAligned(Align(AlignedBuffer::Alignment), AB.begin()));
29 }
30 
TEST(AlignedBuffer,Empty)31 TEST(AlignedBuffer, Empty) {
32   AlignedBuffer AB(0);
33   EXPECT_EQ(std::distance(AB.begin(), AB.end()), 0U);
34 }
35 
TEST(OffsetDistribution,AlignToBegin)36 TEST(OffsetDistribution, AlignToBegin) {
37   StudyConfiguration Conf;
38   Conf.BufferSize = 8192;
39   Conf.AddressAlignment = None;
40 
41   OffsetDistribution OD(Conf);
42   std::default_random_engine Gen;
43   for (size_t I = 0; I <= 10; ++I)
44     EXPECT_EQ(OD(Gen), 0U);
45 }
46 
TEST(OffsetDistribution,NoAlignment)47 TEST(OffsetDistribution, NoAlignment) {
48   StudyConfiguration Conf;
49   Conf.BufferSize = 8192;
50   Conf.Size.To = 1;
51 
52   OffsetDistribution OD(Conf);
53   std::default_random_engine Gen;
54   for (size_t I = 0; I <= 10; ++I)
55     EXPECT_THAT(OD(Gen), AllOf(Ge(0U), Lt(8192U)));
56 }
57 
58 MATCHER_P(IsDivisibleBy, n, "") {
59   *result_listener << "where the remainder is " << (arg % n);
60   return (arg % n) == 0;
61 }
62 
TEST(OffsetDistribution,Aligned)63 TEST(OffsetDistribution, Aligned) {
64   StudyConfiguration Conf;
65   Conf.BufferSize = 8192;
66   Conf.AddressAlignment = Align(16);
67   Conf.Size.To = 1;
68 
69   OffsetDistribution OD(Conf);
70   std::default_random_engine Gen;
71   for (size_t I = 0; I <= 10; ++I)
72     EXPECT_THAT(OD(Gen), AllOf(Ge(0U), Lt(8192U), IsDivisibleBy(16U)));
73 }
74 
TEST(MismatchOffsetDistribution,EqualBufferDisablesDistribution)75 TEST(MismatchOffsetDistribution, EqualBufferDisablesDistribution) {
76   StudyConfiguration Conf;
77   Conf.MemcmpMismatchAt = 0; // buffer are equal.
78 
79   MismatchOffsetDistribution MOD(Conf);
80   EXPECT_FALSE(MOD);
81 }
82 
TEST(MismatchOffsetDistribution,DifferentBufferDisablesDistribution)83 TEST(MismatchOffsetDistribution, DifferentBufferDisablesDistribution) {
84   StudyConfiguration Conf;
85   Conf.MemcmpMismatchAt = 1; // buffer are different.
86 
87   MismatchOffsetDistribution MOD(Conf);
88   EXPECT_FALSE(MOD);
89 }
90 
TEST(MismatchOffsetDistribution,MismatchAt2)91 TEST(MismatchOffsetDistribution, MismatchAt2) {
92   const uint32_t MismatchAt = 2;
93   const uint32_t ToSize = 4;
94   StudyConfiguration Conf;
95   Conf.BufferSize = 16;
96   Conf.MemcmpMismatchAt = MismatchAt; // buffer are different at position 2.
97   Conf.Size.To = ToSize;
98 
99   MismatchOffsetDistribution MOD(Conf);
100   EXPECT_TRUE(MOD);
101   // We test equality up to ToSize (=4) so we need spans of 4 equal bytes spaced
102   // by one mismatch.
103   EXPECT_THAT(MOD.getMismatchIndices(), ElementsAre(5, 9, 13));
104   std::default_random_engine Gen;
105   for (size_t Iterations = 0; Iterations <= 10; ++Iterations) {
106     for (size_t Size = Conf.Size.From; Size <= ToSize; ++Size) {
107       if (Size >= MismatchAt)
108         EXPECT_THAT(MOD(Gen, Size),
109                     AnyOf(5 - MismatchAt, 9 - MismatchAt, 13 - MismatchAt));
110       else
111         EXPECT_THAT(MOD(Gen, Size),
112                     AnyOf(5 - Size - 1, 9 - Size - 1, 13 - Size - 1));
113     }
114   }
115 }
116 
117 } // namespace
118 } // namespace libc_benchmarks
119 } // namespace llvm
120