gecko/mfbt/tests/TestAtomics.cpp

/* 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 "mozilla/Assertions.h"
#include "mozilla/Atomics.h"
#include "mozilla/DebugOnly.h"

#include <stdint.h>

using mozilla::Atomic;
using mozilla::DebugOnly;
using mozilla::MemoryOrdering;
using mozilla::Relaxed;
using mozilla::ReleaseAcquire;
using mozilla::SequentiallyConsistent;

template <typename T, MemoryOrdering Order>
static void
TestTypeWithOrdering()
{
  Atomic<T, Order> atomic(5);
  MOZ_ASSERT(atomic == 5, "Atomic variable did not initialize");

  // Test atomic increment
  MOZ_ASSERT(++atomic == T(6), "Atomic increment did not work");
  MOZ_ASSERT(atomic++ == T(6), "Atomic post-increment did not work");
  MOZ_ASSERT(atomic == T(7), "Atomic post-increment did not work");

  // Test atomic decrement
  MOZ_ASSERT(--atomic == 6, "Atomic decrement did not work");
  MOZ_ASSERT(atomic-- == 6, "Atomic post-decrement did not work");
  MOZ_ASSERT(atomic == 5, "Atomic post-decrement did not work");

  // Test other arithmetic.
  DebugOnly<T> result;
  result = (atomic += T(5));
  MOZ_ASSERT(atomic == T(10), "Atomic += did not work");
  MOZ_ASSERT(result == T(10), "Atomic += returned the wrong value");
  result = (atomic -= T(3));
  MOZ_ASSERT(atomic == T(7), "Atomic -= did not work");
  MOZ_ASSERT(result == T(7), "Atomic -= returned the wrong value");

  // Test assignment
  result = (atomic = T(5));
  MOZ_ASSERT(atomic == T(5), "Atomic assignment failed");
  MOZ_ASSERT(result == T(5), "Atomic assignment returned the wrong value");

  // Test logical operations.
  result = (atomic ^= T(2));
  MOZ_ASSERT(atomic == T(7), "Atomic ^= did not work");
  MOZ_ASSERT(result == T(7), "Atomic ^= returned the wrong value");
  result = (atomic ^= T(4));
  MOZ_ASSERT(atomic == T(3), "Atomic ^= did not work");
  MOZ_ASSERT(result == T(3), "Atomic ^= returned the wrong value");
  result = (atomic |= T(8));
  MOZ_ASSERT(atomic == T(11), "Atomic |= did not work");
  MOZ_ASSERT(result == T(11), "Atomic |= returned the wrong value");
  result = (atomic |= T(8));
  MOZ_ASSERT(atomic == T(11), "Atomic |= did not work");
  MOZ_ASSERT(result == T(11), "Atomic |= returned the wrong value");
  result = (atomic &= T(12));
  MOZ_ASSERT(atomic == T(8), "Atomic &= did not work");
  MOZ_ASSERT(result == T(8), "Atomic &= returned the wrong value");

  // Test exchange.
  atomic = T(30);
  result = atomic.exchange(42);
  MOZ_ASSERT(atomic == T(42), "Atomic exchange did not work");
  MOZ_ASSERT(result == T(30), "Atomic exchange returned the wrong value");

  // Test CAS.
  atomic = T(1);
  DebugOnly<bool> boolResult = atomic.compareExchange(0, 2);
  MOZ_ASSERT(!boolResult, "CAS should have returned false.");
  MOZ_ASSERT(atomic == T(1), "CAS shouldn't have done anything.");

  boolResult = atomic.compareExchange(1, 42);
  MOZ_ASSERT(boolResult, "CAS should have succeeded.");
  MOZ_ASSERT(atomic == T(42), "CAS should have changed atomic's value.");
}

template<typename T, MemoryOrdering Order>
static void
TestPointerWithOrdering()
{
  T array1[10];
  Atomic<T*, Order> atomic(array1);
  MOZ_ASSERT(atomic == array1, "Atomic variable did not initialize");

  // Test atomic increment
  MOZ_ASSERT(++atomic == array1 + 1, "Atomic increment did not work");
  MOZ_ASSERT(atomic++ == array1 + 1, "Atomic post-increment did not work");
  MOZ_ASSERT(atomic == array1 + 2, "Atomic post-increment did not work");

  // Test atomic decrement
  MOZ_ASSERT(--atomic == array1 + 1, "Atomic decrement did not work");
  MOZ_ASSERT(atomic-- == array1 + 1, "Atomic post-decrement did not work");
  MOZ_ASSERT(atomic == array1, "Atomic post-decrement did not work");

  // Test other arithmetic operations
  DebugOnly<T*> result;
  result = (atomic += 2);
  MOZ_ASSERT(atomic == array1 + 2, "Atomic += did not work");
  MOZ_ASSERT(result == array1 + 2, "Atomic += returned the wrong value");
  result = (atomic -= 1);
  MOZ_ASSERT(atomic == array1 + 1, "Atomic -= did not work");
  MOZ_ASSERT(result == array1 + 1, "Atomic -= returned the wrong value");

  // Test stores
  result = (atomic = array1);
  MOZ_ASSERT(atomic == array1, "Atomic assignment did not work");
  MOZ_ASSERT(result == array1, "Atomic assignment returned the wrong value");

  // Test exchange
  atomic = array1 + 2;
  result = atomic.exchange(array1);
  MOZ_ASSERT(atomic == array1, "Atomic exchange did not work");
  MOZ_ASSERT(result == array1 + 2, "Atomic exchange returned the wrong value");

  atomic = array1;
  DebugOnly<bool> boolResult = atomic.compareExchange(array1 + 1, array1 + 2);
  MOZ_ASSERT(!boolResult, "CAS should have returned false.");
  MOZ_ASSERT(atomic == array1, "CAS shouldn't have done anything.");

  boolResult = atomic.compareExchange(array1, array1 + 3);
  MOZ_ASSERT(boolResult, "CAS should have succeeded.");
  MOZ_ASSERT(atomic == array1 + 3, "CAS should have changed atomic's value.");
}

template <typename T>
static void
TestType()
{
  TestTypeWithOrdering<T, SequentiallyConsistent>();
  TestTypeWithOrdering<T, ReleaseAcquire>();
  TestTypeWithOrdering<T, Relaxed>();
}

template<typename T>
static void
TestPointer()
{
  TestPointerWithOrdering<T, SequentiallyConsistent>();
  TestPointerWithOrdering<T, ReleaseAcquire>();
  TestPointerWithOrdering<T, Relaxed>();
}

int main()
{
  TestType<uint32_t>();
  TestType<int32_t>();
  TestType<intptr_t>();
  TestType<uintptr_t>();
  TestPointer<int>();
  TestPointer<float>();
  TestPointer<uint16_t*>();
  TestPointer<uint32_t*>();
}