gecko-dev/mozglue/tests/TestBaseProfiler.cpp

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "BaseProfiler.h"

#ifdef MOZ_BASE_PROFILER

#  include "mozilla/leb128iterator.h"
#  include "mozilla/PowerOfTwo.h"

#  include "mozilla/Attributes.h"
#  include "mozilla/Vector.h"

#  if defined(_MSC_VER)
#    include <windows.h>
#    include <mmsystem.h>
#    include <process.h>
#  else
#    include <time.h>
#    include <unistd.h>
#  endif

using namespace mozilla;

MOZ_MAYBE_UNUSED static void SleepMilli(unsigned aMilliseconds) {
#  if defined(_MSC_VER)
  Sleep(aMilliseconds);
#  else
  struct timespec ts;
  ts.tv_sec = aMilliseconds / 1000;
  ts.tv_nsec = long(aMilliseconds % 1000) * 1000000;
  struct timespec tr;
  while (nanosleep(&ts, &tr)) {
    if (errno == EINTR) {
      ts = tr;
    } else {
      printf("nanosleep() -> %s\n", strerror(errno));
      exit(1);
    }
  }
#  endif
}

void TestPowerOfTwoMask() {
  printf("TestPowerOfTwoMask...\n");

  static_assert(MakePowerOfTwoMask<uint32_t, 0>().MaskValue() == 0, "");
  constexpr PowerOfTwoMask<uint32_t> c0 = MakePowerOfTwoMask<uint32_t, 0>();
  MOZ_RELEASE_ASSERT(c0.MaskValue() == 0);

  static_assert(MakePowerOfTwoMask<uint32_t, 0xFFu>().MaskValue() == 0xFFu, "");
  constexpr PowerOfTwoMask<uint32_t> cFF =
      MakePowerOfTwoMask<uint32_t, 0xFFu>();
  MOZ_RELEASE_ASSERT(cFF.MaskValue() == 0xFFu);

  static_assert(
      MakePowerOfTwoMask<uint32_t, 0xFFFFFFFFu>().MaskValue() == 0xFFFFFFFFu,
      "");
  constexpr PowerOfTwoMask<uint32_t> cFFFFFFFF =
      MakePowerOfTwoMask<uint32_t, 0xFFFFFFFFu>();
  MOZ_RELEASE_ASSERT(cFFFFFFFF.MaskValue() == 0xFFFFFFFFu);

  struct TestDataU32 {
    uint32_t mInput;
    uint32_t mMask;
  };
  // clang-format off
  TestDataU32 tests[] = {
    { 0, 0 },
    { 1, 1 },
    { 2, 3 },
    { 3, 3 },
    { 4, 7 },
    { 5, 7 },
    { (1u << 31) - 1, (1u << 31) - 1 },
    { (1u << 31), uint32_t(-1) },
    { (1u << 31) + 1, uint32_t(-1) },
    { uint32_t(-1), uint32_t(-1) }
  };
  // clang-format on
  for (const TestDataU32& test : tests) {
    PowerOfTwoMask<uint32_t> p2m(test.mInput);
    MOZ_RELEASE_ASSERT(p2m.MaskValue() == test.mMask);
    for (const TestDataU32& inner : tests) {
      if (p2m.MaskValue() != uint32_t(-1)) {
        MOZ_RELEASE_ASSERT((inner.mInput % p2m) ==
                           (inner.mInput % (p2m.MaskValue() + 1)));
      }
      MOZ_RELEASE_ASSERT((inner.mInput & p2m) == (inner.mInput % p2m));
      MOZ_RELEASE_ASSERT((p2m & inner.mInput) == (inner.mInput & p2m));
    }
  }

  printf("TestPowerOfTwoMask done\n");
}

void TestPowerOfTwo() {
  printf("TestPowerOfTwo...\n");

  static_assert(MakePowerOfTwo<uint32_t, 1>().Value() == 1, "");
  constexpr PowerOfTwo<uint32_t> c1 = MakePowerOfTwo<uint32_t, 1>();
  MOZ_RELEASE_ASSERT(c1.Value() == 1);
  static_assert(MakePowerOfTwo<uint32_t, 1>().Mask().MaskValue() == 0, "");

  static_assert(MakePowerOfTwo<uint32_t, 128>().Value() == 128, "");
  constexpr PowerOfTwo<uint32_t> c128 = MakePowerOfTwo<uint32_t, 128>();
  MOZ_RELEASE_ASSERT(c128.Value() == 128);
  static_assert(MakePowerOfTwo<uint32_t, 128>().Mask().MaskValue() == 127, "");

  static_assert(MakePowerOfTwo<uint32_t, 0x80000000u>().Value() == 0x80000000u,
                "");
  constexpr PowerOfTwo<uint32_t> cMax = MakePowerOfTwo<uint32_t, 0x80000000u>();
  MOZ_RELEASE_ASSERT(cMax.Value() == 0x80000000u);
  static_assert(
      MakePowerOfTwo<uint32_t, 0x80000000u>().Mask().MaskValue() == 0x7FFFFFFFu,
      "");

  struct TestDataU32 {
    uint32_t mInput;
    uint32_t mValue;
    uint32_t mMask;
  };
  // clang-format off
  TestDataU32 tests[] = {
    { 0, 1, 0 },
    { 1, 1, 0 },
    { 2, 2, 1 },
    { 3, 4, 3 },
    { 4, 4, 3 },
    { 5, 8, 7 },
    { (1u << 31) - 1, (1u << 31), (1u << 31) - 1 },
    { (1u << 31), (1u << 31), (1u << 31) - 1 },
    { (1u << 31) + 1, (1u << 31), (1u << 31) - 1 },
    { uint32_t(-1), (1u << 31), (1u << 31) - 1 }
  };
  // clang-format on
  for (const TestDataU32& test : tests) {
    PowerOfTwo<uint32_t> p2(test.mInput);
    MOZ_RELEASE_ASSERT(p2.Value() == test.mValue);
    MOZ_RELEASE_ASSERT(p2.MaskValue() == test.mMask);
    PowerOfTwoMask<uint32_t> p2m = p2.Mask();
    MOZ_RELEASE_ASSERT(p2m.MaskValue() == test.mMask);
    for (const TestDataU32& inner : tests) {
      MOZ_RELEASE_ASSERT((inner.mInput % p2) == (inner.mInput % p2.Value()));
    }
  }

  printf("TestPowerOfTwo done\n");
}

void TestLEB128() {
  printf("TestLEB128...\n");

  MOZ_RELEASE_ASSERT(ULEB128MaxSize<uint8_t>() == 2);
  MOZ_RELEASE_ASSERT(ULEB128MaxSize<uint16_t>() == 3);
  MOZ_RELEASE_ASSERT(ULEB128MaxSize<uint32_t>() == 5);
  MOZ_RELEASE_ASSERT(ULEB128MaxSize<uint64_t>() == 10);

  struct TestDataU64 {
    uint64_t mValue;
    unsigned mSize;
    const char* mBytes;
  };
  // clang-format off
  TestDataU64 tests[] = {
    // Small numbers should keep their normal byte representation.
    {                  0u,  1, "\0" },
    {                  1u,  1, "\x01" },

    // 0111 1111 (127, or 0x7F) is the highest number that fits into a single
    // LEB128 byte. It gets encoded as 0111 1111, note the most significant bit
    // is off.
    {               0x7Fu,  1, "\x7F" },

    // Next number: 128, or 0x80.
    //   Original data representation:  1000 0000
    //     Broken up into groups of 7:         1  0000000
    // Padded with 0 (msB) or 1 (lsB):  00000001 10000000
    //            Byte representation:  0x01     0x80
    //            Little endian order:  -> 0x80 0x01
    {               0x80u,  2, "\x80\x01" },

    // Next: 129, or 0x81 (showing that we don't lose low bits.)
    //   Original data representation:  1000 0001
    //     Broken up into groups of 7:         1  0000001
    // Padded with 0 (msB) or 1 (lsB):  00000001 10000001
    //            Byte representation:  0x01     0x81
    //            Little endian order:  -> 0x81 0x01
    {               0x81u,  2, "\x81\x01" },

    // Highest 8-bit number: 255, or 0xFF.
    //   Original data representation:  1111 1111
    //     Broken up into groups of 7:         1  1111111
    // Padded with 0 (msB) or 1 (lsB):  00000001 11111111
    //            Byte representation:  0x01     0xFF
    //            Little endian order:  -> 0xFF 0x01
    {               0xFFu,  2, "\xFF\x01" },

    // Next: 256, or 0x100.
    //   Original data representation:  1 0000 0000
    //     Broken up into groups of 7:        10  0000000
    // Padded with 0 (msB) or 1 (lsB):  00000010 10000000
    //            Byte representation:  0x10     0x80
    //            Little endian order:  -> 0x80 0x02
    {              0x100u,  2, "\x80\x02" },

    // Highest 32-bit number: 0xFFFFFFFF (8 bytes, all bits set).
    // Original: 1111 1111 1111 1111 1111 1111 1111 1111
    // Groups:     1111  1111111  1111111  1111111  1111111
    // Padded: 00001111 11111111 11111111 11111111 11111111
    // Bytes:  0x0F     0xFF     0xFF     0xFF     0xFF
    // Little Endian: -> 0xFF 0xFF 0xFF 0xFF 0x0F
    {         0xFFFFFFFFu,  5, "\xFF\xFF\xFF\xFF\x0F" },

    // Highest 64-bit number: 0xFFFFFFFFFFFFFFFF (16 bytes, all bits set).
    // 64 bits, that's 9 groups of 7 bits, plus 1 (most significant) bit.
    { 0xFFFFFFFFFFFFFFFFu, 10, "\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\x01" }
  };
  // clang-format on

  for (const TestDataU64& test : tests) {
    MOZ_RELEASE_ASSERT(ULEB128Size(test.mValue) == test.mSize);
    // Prepare a buffer that can accomodate the largest-possible LEB128.
    uint8_t buffer[ULEB128MaxSize<uint64_t>()];
    // Use a pointer into the buffer as iterator.
    uint8_t* p = buffer;
    // And write the LEB128.
    WriteULEB128(test.mValue, p);
    // Pointer (iterator) should have advanced just past the expected LEB128
    // size.
    MOZ_RELEASE_ASSERT(p == buffer + test.mSize);
    // Check expected bytes.
    for (unsigned i = 0; i < test.mSize; ++i) {
      MOZ_RELEASE_ASSERT(buffer[i] == uint8_t(test.mBytes[i]));
    }
    // Move pointer (iterator) back to start of buffer.
    p = buffer;
    // And read the LEB128 we wrote above.
    uint64_t read = ReadULEB128<uint64_t>(p);
    // Pointer (iterator) should have also advanced just past the expected
    // LEB128 size.
    MOZ_RELEASE_ASSERT(p == buffer + test.mSize);
    // And check the read value.
    MOZ_RELEASE_ASSERT(read == test.mValue);
  }

  printf("TestLEB128 done\n");
}

// Increase the depth, to a maximum (to avoid too-deep recursion).
static constexpr size_t NextDepth(size_t aDepth) {
  constexpr size_t MAX_DEPTH = 128;
  return (aDepth < MAX_DEPTH) ? (aDepth + 1) : aDepth;
}

// Compute fibonacci the hard way (recursively: `f(n)=f(n-1)+f(n-2)`), and
// prevent inlining.
// The template parameter makes each depth be a separate function, to better
// distinguish them in the profiler output.
template <size_t DEPTH = 0>
MOZ_NEVER_INLINE unsigned long long Fibonacci(unsigned long long n) {
  if (n == 0) {
    return 0;
  }
  if (n == 1) {
    return 1;
  }
  unsigned long long f2 = Fibonacci<NextDepth(DEPTH)>(n - 2);
  if (DEPTH == 0) {
    BASE_PROFILER_ADD_MARKER("Half-way through Fibonacci", OTHER);
  }
  unsigned long long f1 = Fibonacci<NextDepth(DEPTH)>(n - 1);
  return f2 + f1;
}

void TestProfiler() {
  printf("TestProfiler starting -- pid: %d, tid: %d\n",
         baseprofiler::profiler_current_process_id(),
         baseprofiler::profiler_current_thread_id());
  // ::SleepMilli(10000);

  // Test dependencies.
  TestPowerOfTwoMask();
  TestPowerOfTwo();
  TestLEB128();

  {
    printf("profiler_init()...\n");
    AUTO_BASE_PROFILER_INIT;

    MOZ_RELEASE_ASSERT(!baseprofiler::profiler_is_active());
    MOZ_RELEASE_ASSERT(!baseprofiler::profiler_thread_is_being_profiled());
    MOZ_RELEASE_ASSERT(!baseprofiler::profiler_thread_is_sleeping());

    printf("profiler_start()...\n");
    Vector<const char*> filters;
    // Profile all registered threads.
    MOZ_RELEASE_ASSERT(filters.append(""));
    const uint32_t features = baseprofiler::ProfilerFeature::Leaf |
                              baseprofiler::ProfilerFeature::StackWalk |
                              baseprofiler::ProfilerFeature::Threads;
    baseprofiler::profiler_start(baseprofiler::BASE_PROFILER_DEFAULT_ENTRIES,
                                 BASE_PROFILER_DEFAULT_INTERVAL, features,
                                 filters.begin(), filters.length());

    MOZ_RELEASE_ASSERT(baseprofiler::profiler_is_active());
    MOZ_RELEASE_ASSERT(baseprofiler::profiler_thread_is_being_profiled());
    MOZ_RELEASE_ASSERT(!baseprofiler::profiler_thread_is_sleeping());

    {
      AUTO_BASE_PROFILER_TEXT_MARKER_CAUSE("fibonacci", "First leaf call",
                                           OTHER, nullptr);
      static const unsigned long long fibStart = 40;
      printf("Fibonacci(%llu)...\n", fibStart);
      AUTO_BASE_PROFILER_LABEL("Label around Fibonacci", OTHER);
      unsigned long long f = Fibonacci(fibStart);
      printf("Fibonacci(%llu) = %llu\n", fibStart, f);
    }

    printf("Sleep 1s...\n");
    {
      AUTO_BASE_PROFILER_THREAD_SLEEP;
      SleepMilli(1000);
    }

    printf("baseprofiler_save_profile_to_file()...\n");
    baseprofiler::profiler_save_profile_to_file("TestProfiler_profile.json");

    printf("profiler_stop()...\n");
    baseprofiler::profiler_stop();

    MOZ_RELEASE_ASSERT(!baseprofiler::profiler_is_active());
    MOZ_RELEASE_ASSERT(!baseprofiler::profiler_thread_is_being_profiled());
    MOZ_RELEASE_ASSERT(!baseprofiler::profiler_thread_is_sleeping());

    printf("profiler_shutdown()...\n");
  }

  printf("TestProfiler done\n");
}

#else  // MOZ_BASE_PROFILER

// Testing that macros are still #defined (but do nothing) when
// MOZ_BASE_PROFILER is disabled.
void TestProfiler() {
  // These don't need to make sense, we just want to know that they're defined
  // and don't do anything.
  AUTO_BASE_PROFILER_INIT;

  // This wouldn't build if the macro did output its arguments.
  AUTO_BASE_PROFILER_TEXT_MARKER_CAUSE(catch, catch, catch, catch);

  AUTO_BASE_PROFILER_LABEL(catch, catch);

  AUTO_BASE_PROFILER_THREAD_SLEEP;
}

#endif  // MOZ_BASE_PROFILER else

int main() {
  // Note that there are two `TestProfiler` functions above, depending on
  // whether MOZ_BASE_PROFILER is #defined.
  TestProfiler();

  return 0;
}