chore: import upstream snapshot with attribution

2026-07-13 13:29:29 +08:00
commit f52cf32e56
1718 changed files with 366293 additions and 0 deletions
@@ -0,0 +1,241 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "butil/atomicops.h"
+
+#include <stdint.h>
+#include <string.h>
+
+#include <gtest/gtest.h>
+
+template <class AtomicType>
+static void TestAtomicIncrement() {
+  // For now, we just test single threaded execution
+
+  // use a guard value to make sure the NoBarrier_AtomicIncrement doesn't go
+  // outside the expected address bounds.  This is in particular to
+  // test that some future change to the asm code doesn't cause the
+  // 32-bit NoBarrier_AtomicIncrement doesn't do the wrong thing on 64-bit
+  // machines.
+  struct {
+    AtomicType prev_word;
+    AtomicType count;
+    AtomicType next_word;
+  } s;
+
+  AtomicType prev_word_value, next_word_value;
+  memset(&prev_word_value, 0xFF, sizeof(AtomicType));
+  memset(&next_word_value, 0xEE, sizeof(AtomicType));
+
+  s.prev_word = prev_word_value;
+  s.count = 0;
+  s.next_word = next_word_value;
+
+  EXPECT_EQ(butil::subtle::NoBarrier_AtomicIncrement(&s.count, 1), 1);
+  EXPECT_EQ(s.count, 1);
+  EXPECT_EQ(s.prev_word, prev_word_value);
+  EXPECT_EQ(s.next_word, next_word_value);
+
+  EXPECT_EQ(butil::subtle::NoBarrier_AtomicIncrement(&s.count, 2), 3);
+  EXPECT_EQ(s.count, 3);
+  EXPECT_EQ(s.prev_word, prev_word_value);
+  EXPECT_EQ(s.next_word, next_word_value);
+
+  EXPECT_EQ(butil::subtle::NoBarrier_AtomicIncrement(&s.count, 3), 6);
+  EXPECT_EQ(s.count, 6);
+  EXPECT_EQ(s.prev_word, prev_word_value);
+  EXPECT_EQ(s.next_word, next_word_value);
+
+  EXPECT_EQ(butil::subtle::NoBarrier_AtomicIncrement(&s.count, -3), 3);
+  EXPECT_EQ(s.count, 3);
+  EXPECT_EQ(s.prev_word, prev_word_value);
+  EXPECT_EQ(s.next_word, next_word_value);
+
+  EXPECT_EQ(butil::subtle::NoBarrier_AtomicIncrement(&s.count, -2), 1);
+  EXPECT_EQ(s.count, 1);
+  EXPECT_EQ(s.prev_word, prev_word_value);
+  EXPECT_EQ(s.next_word, next_word_value);
+
+  EXPECT_EQ(butil::subtle::NoBarrier_AtomicIncrement(&s.count, -1), 0);
+  EXPECT_EQ(s.count, 0);
+  EXPECT_EQ(s.prev_word, prev_word_value);
+  EXPECT_EQ(s.next_word, next_word_value);
+
+  EXPECT_EQ(butil::subtle::NoBarrier_AtomicIncrement(&s.count, -1), -1);
+  EXPECT_EQ(s.count, -1);
+  EXPECT_EQ(s.prev_word, prev_word_value);
+  EXPECT_EQ(s.next_word, next_word_value);
+
+  EXPECT_EQ(butil::subtle::NoBarrier_AtomicIncrement(&s.count, -4), -5);
+  EXPECT_EQ(s.count, -5);
+  EXPECT_EQ(s.prev_word, prev_word_value);
+  EXPECT_EQ(s.next_word, next_word_value);
+
+  EXPECT_EQ(butil::subtle::NoBarrier_AtomicIncrement(&s.count, 5), 0);
+  EXPECT_EQ(s.count, 0);
+  EXPECT_EQ(s.prev_word, prev_word_value);
+  EXPECT_EQ(s.next_word, next_word_value);
+}
+
+
+#define NUM_BITS(T) (sizeof(T) * 8)
+
+
+template <class AtomicType>
+static void TestCompareAndSwap() {
+  AtomicType value = 0;
+  AtomicType prev = butil::subtle::NoBarrier_CompareAndSwap(&value, 0, 1);
+  EXPECT_EQ(1, value);
+  EXPECT_EQ(0, prev);
+
+  // Use test value that has non-zero bits in both halves, more for testing
+  // 64-bit implementation on 32-bit platforms.
+  const AtomicType k_test_val = (static_cast<uint64_t>(1) <<
+                                 (NUM_BITS(AtomicType) - 2)) + 11;
+  value = k_test_val;
+  prev = butil::subtle::NoBarrier_CompareAndSwap(&value, 0, 5);
+  EXPECT_EQ(k_test_val, value);
+  EXPECT_EQ(k_test_val, prev);
+
+  value = k_test_val;
+  prev = butil::subtle::NoBarrier_CompareAndSwap(&value, k_test_val, 5);
+  EXPECT_EQ(5, value);
+  EXPECT_EQ(k_test_val, prev);
+}
+
+
+template <class AtomicType>
+static void TestAtomicExchange() {
+  AtomicType value = 0;
+  AtomicType new_value = butil::subtle::NoBarrier_AtomicExchange(&value, 1);
+  EXPECT_EQ(1, value);
+  EXPECT_EQ(0, new_value);
+
+  // Use test value that has non-zero bits in both halves, more for testing
+  // 64-bit implementation on 32-bit platforms.
+  const AtomicType k_test_val = (static_cast<uint64_t>(1) <<
+                                 (NUM_BITS(AtomicType) - 2)) + 11;
+  value = k_test_val;
+  new_value = butil::subtle::NoBarrier_AtomicExchange(&value, k_test_val);
+  EXPECT_EQ(k_test_val, value);
+  EXPECT_EQ(k_test_val, new_value);
+
+  value = k_test_val;
+  new_value = butil::subtle::NoBarrier_AtomicExchange(&value, 5);
+  EXPECT_EQ(5, value);
+  EXPECT_EQ(k_test_val, new_value);
+}
+
+
+template <class AtomicType>
+static void TestAtomicIncrementBounds() {
+  // Test at rollover boundary between int_max and int_min
+  AtomicType test_val = (static_cast<uint64_t>(1) <<
+                         (NUM_BITS(AtomicType) - 1));
+  AtomicType value = -1 ^ test_val;
+  AtomicType new_value = butil::subtle::NoBarrier_AtomicIncrement(&value, 1);
+  EXPECT_EQ(test_val, value);
+  EXPECT_EQ(value, new_value);
+
+  butil::subtle::NoBarrier_AtomicIncrement(&value, -1);
+  EXPECT_EQ(-1 ^ test_val, value);
+
+  // Test at 32-bit boundary for 64-bit atomic type.
+  test_val = static_cast<uint64_t>(1) << (NUM_BITS(AtomicType) / 2);
+  value = test_val - 1;
+  new_value = butil::subtle::NoBarrier_AtomicIncrement(&value, 1);
+  EXPECT_EQ(test_val, value);
+  EXPECT_EQ(value, new_value);
+
+  butil::subtle::NoBarrier_AtomicIncrement(&value, -1);
+  EXPECT_EQ(test_val - 1, value);
+}
+
+// Return an AtomicType with the value 0xa5a5a5..
+template <class AtomicType>
+static AtomicType TestFillValue() {
+  AtomicType val = 0;
+  memset(&val, 0xa5, sizeof(AtomicType));
+  return val;
+}
+
+// This is a simple sanity check that values are correct. Not testing
+// atomicity
+template <class AtomicType>
+static void TestStore() {
+  const AtomicType kVal1 = TestFillValue<AtomicType>();
+  const AtomicType kVal2 = static_cast<AtomicType>(-1);
+
+  AtomicType value;
+
+  butil::subtle::NoBarrier_Store(&value, kVal1);
+  EXPECT_EQ(kVal1, value);
+  butil::subtle::NoBarrier_Store(&value, kVal2);
+  EXPECT_EQ(kVal2, value);
+
+  butil::subtle::Acquire_Store(&value, kVal1);
+  EXPECT_EQ(kVal1, value);
+  butil::subtle::Acquire_Store(&value, kVal2);
+  EXPECT_EQ(kVal2, value);
+
+  butil::subtle::Release_Store(&value, kVal1);
+  EXPECT_EQ(kVal1, value);
+  butil::subtle::Release_Store(&value, kVal2);
+  EXPECT_EQ(kVal2, value);
+}
+
+// This is a simple sanity check that values are correct. Not testing
+// atomicity
+template <class AtomicType>
+static void TestLoad() {
+  const AtomicType kVal1 = TestFillValue<AtomicType>();
+  const AtomicType kVal2 = static_cast<AtomicType>(-1);
+
+  AtomicType value;
+
+  value = kVal1;
+  EXPECT_EQ(kVal1, butil::subtle::NoBarrier_Load(&value));
+  value = kVal2;
+  EXPECT_EQ(kVal2, butil::subtle::NoBarrier_Load(&value));
+
+  value = kVal1;
+  EXPECT_EQ(kVal1, butil::subtle::Acquire_Load(&value));
+  value = kVal2;
+  EXPECT_EQ(kVal2, butil::subtle::Acquire_Load(&value));
+
+  value = kVal1;
+  EXPECT_EQ(kVal1, butil::subtle::Release_Load(&value));
+  value = kVal2;
+  EXPECT_EQ(kVal2, butil::subtle::Release_Load(&value));
+}
+
+TEST(AtomicOpsTest, Inc) {
+  TestAtomicIncrement<butil::subtle::Atomic32>();
+  TestAtomicIncrement<butil::subtle::AtomicWord>();
+}
+
+TEST(AtomicOpsTest, CompareAndSwap) {
+  TestCompareAndSwap<butil::subtle::Atomic32>();
+  TestCompareAndSwap<butil::subtle::AtomicWord>();
+}
+
+TEST(AtomicOpsTest, Exchange) {
+  TestAtomicExchange<butil::subtle::Atomic32>();
+  TestAtomicExchange<butil::subtle::AtomicWord>();
+}
+
+TEST(AtomicOpsTest, IncrementBounds) {
+  TestAtomicIncrementBounds<butil::subtle::Atomic32>();
+  TestAtomicIncrementBounds<butil::subtle::AtomicWord>();
+}
+
+TEST(AtomicOpsTest, Store) {
+  TestStore<butil::subtle::Atomic32>();
+  TestStore<butil::subtle::AtomicWord>();
+}
+
+TEST(AtomicOpsTest, Load) {
+  TestLoad<butil::subtle::Atomic32>();
+  TestLoad<butil::subtle::AtomicWord>();
+}