libc/benchmarks/LibcMemoryBenchmarkTest.cpp

   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
  26 TEST(AlignedBuffer, IsAligned) {
  27   AlignedBuffer AB(0);
  28   EXPECT_TRUE(isAddrAligned(Align(AlignedBuffer::Alignment), AB.begin()));
  29 }
  30
  31 TEST(AlignedBuffer, Empty) {
  32   AlignedBuffer AB(0);
  33   EXPECT_EQ(std::distance(AB.begin(), AB.end()), 0U);
  34 }
  35
  36 TEST(OffsetDistribution, AlignToBegin) {
  37   const size_t BufferSize = 8192;
  38   OffsetDistribution OD(BufferSize, 1024, None);
  39   std::default_random_engine Gen;
  40   for (size_t I = 0; I <= 10; ++I)
  41     EXPECT_EQ(OD(Gen), 0U);
  42 }
  43
  44 TEST(OffsetDistribution, NoAlignment) {
  45   const size_t BufferSize = 8192;
  46   OffsetDistribution OD(BufferSize, 1, Align(1));
  47   std::default_random_engine Gen;
  48   for (size_t I = 0; I <= 10; ++I)
  49     EXPECT_THAT(OD(Gen), AllOf(Ge(0U), Lt(8192U)));
  50 }
  51
  52 MATCHER_P(IsDivisibleBy, n, "") {
  53   *result_listener << "where the remainder is " << (arg % n);
  54   return (arg % n) == 0;
  55 }
  56
  57 TEST(OffsetDistribution, Aligned) {
  58   const size_t BufferSize = 8192;
  59   OffsetDistribution OD(BufferSize, 1, Align(16));
  60   std::default_random_engine Gen;
  61   for (size_t I = 0; I <= 10; ++I)
  62     EXPECT_THAT(OD(Gen), AllOf(Ge(0U), Lt(8192U), IsDivisibleBy(16U)));
  63 }
  64
  65 TEST(MismatchOffsetDistribution, EqualBufferDisablesDistribution) {
  66   const size_t BufferSize = 8192;
  67   const uint32_t MismatchAt = 0; // buffer are equal.
  68
  69   MismatchOffsetDistribution MOD(BufferSize, 1024, MismatchAt);
  70   EXPECT_FALSE(MOD);
  71 }
  72
  73 TEST(MismatchOffsetDistribution, DifferentBufferDisablesDistribution) {
  74   const size_t BufferSize = 8192;
  75   const uint32_t MismatchAt = 1; // buffer are different.
  76
  77   MismatchOffsetDistribution MOD(BufferSize, 1024, MismatchAt);
  78   EXPECT_FALSE(MOD);
  79 }
  80
  81 TEST(MismatchOffsetDistribution, MismatchAt2) {
  82   const size_t BufferSize = 16;
  83   const uint32_t MismatchAt = 2; // buffer are different at position 2.
  84   const uint32_t MaxSize = 4;
  85
  86   MismatchOffsetDistribution MOD(BufferSize, MaxSize, MismatchAt);
  87   EXPECT_TRUE(MOD);
  88   // We test equality up to MaxSize (=4) so we need spans of 4 equal bytes
  89   // spaced by one mismatch.
  90   EXPECT_THAT(MOD.getMismatchIndices(), ElementsAre(5, 9, 13));
  91   std::default_random_engine Gen;
  92   for (size_t Iterations = 0; Iterations <= 10; ++Iterations) {
  93     for (size_t Size = 0; Size <= MaxSize; ++Size) {
  94       if (Size >= MismatchAt)
  95         EXPECT_THAT(MOD(Gen, Size),
  96                     AnyOf(5 - MismatchAt, 9 - MismatchAt, 13 - MismatchAt));
  97       else
  98         EXPECT_THAT(MOD(Gen, Size),
  99                     AnyOf(5 - Size - 1, 9 - Size - 1, 13 - Size - 1));
 100     }
 101   }
 102 }
 103
 104 } // namespace
 105 } // namespace libc_benchmarks
 106 } // namespace llvm