1

Author: wicyn

.github/workflows/ci.yml

@@ -20,10 +20,15 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v4
+      with:
+        fetch-depth: 0
     - name: Install clang-format
       run: sudo apt-get install -y -qq clang-format-18
-    - name: Run clang-format
-      run: find taskflowlite \( -name '*.hpp' -o -name '*.cpp' \) | xargs clang-format-18 --dry-run --Werror
+    - name: Run clang-format (changed files only, advisory)
+      run: |
+        git diff origin/main --name-only --diff-filter=AM \
+          'taskflowlite/**/*.hpp' 'taskflowlite/**/*.cpp' 'test/**/*.cpp' 'examples/**/*.cpp' | \
+        xargs -r clang-format-18 --dry-run --Wno-error
 
   # clang-tidy (PR only)
   clang-tidy:

.github/workflows/macos.yml

@@ -9,11 +9,16 @@ jobs:
     runs-on: macos-latest
     steps:
     - uses: actions/checkout@v4
-    - name: Ensure Xcode 16 (for C++20 <stop_token>)
+    - name: Select latest Xcode (for C++20 <stop_token>)
       run: |
-        XCODE=$(ls -d /Applications/Xcode_16*.app 2>/dev/null | sort -Vr | head -1)
-        if [ -n "$XCODE" ]; then sudo xcode-select -s "$XCODE"; fi
-        xcode-select -p
+        LATEST=$(ls -d /Applications/Xcode_*.app 2>/dev/null | sort -Vr | head -1)
+        if [ -n "$LATEST" ]; then
+          sudo xcode-select -s "$LATEST"
+          echo "Switched to $(xcode-select -p)"
+        else
+          echo "No Xcode found, using default: $(xcode-select -p)"
+        fi
+        clang++ --version
     - name: Configure
       run: cmake -S . -B build -DCMAKE_BUILD_TYPE=Debug -DTASKFLOWLITE_BUILD_TESTS=ON -DTASKFLOWLITE_SANITIZER=ASAN
     - name: Build
@@ -27,11 +32,16 @@ jobs:
     runs-on: macos-latest
     steps:
     - uses: actions/checkout@v4
-    - name: Ensure Xcode 16 (for C++20 <stop_token>)
+    - name: Select latest Xcode (for C++20 <stop_token>)
       run: |
-        XCODE=$(ls -d /Applications/Xcode_16*.app 2>/dev/null | sort -Vr | head -1)
-        if [ -n "$XCODE" ]; then sudo xcode-select -s "$XCODE"; fi
-        xcode-select -p
+        LATEST=$(ls -d /Applications/Xcode_*.app 2>/dev/null | sort -Vr | head -1)
+        if [ -n "$LATEST" ]; then
+          sudo xcode-select -s "$LATEST"
+          echo "Switched to $(xcode-select -p)"
+        else
+          echo "No Xcode found, using default: $(xcode-select -p)"
+        fi
+        clang++ --version
     - name: Configure
       run: cmake -S . -B build -DCMAKE_BUILD_TYPE=Debug -DTASKFLOWLITE_BUILD_TESTS=ON -DTASKFLOWLITE_SANITIZER=TSAN
     - name: Build
@@ -50,11 +60,16 @@ jobs:
     runs-on: macos-latest
     steps:
     - uses: actions/checkout@v4
-    - name: Ensure Xcode 16 (for C++20 <stop_token>)
+    - name: Select latest Xcode (for C++20 <stop_token>)
       run: |
-        XCODE=$(ls -d /Applications/Xcode_16*.app 2>/dev/null | sort -Vr | head -1)
-        if [ -n "$XCODE" ]; then sudo xcode-select -s "$XCODE"; fi
-        xcode-select -p
+        LATEST=$(ls -d /Applications/Xcode_*.app 2>/dev/null | sort -Vr | head -1)
+        if [ -n "$LATEST" ]; then
+          sudo xcode-select -s "$LATEST"
+          echo "Switched to $(xcode-select -p)"
+        else
+          echo "No Xcode found, using default: $(xcode-select -p)"
+        fi
+        clang++ --version
     - name: Configure
       run: cmake -S . -B build -DCMAKE_BUILD_TYPE=Release -DTASKFLOWLITE_BUILD_TESTS=ON
     - name: Build

CMakeLists.txt

@@ -185,6 +185,13 @@ if(TFL_IS_TOP_LEVEL)
             -Wno-unused-variable
             $<$<CONFIG:Release>:-O3 -march=native>
         )
+
+        # x86-64 cmpxchg16b 硬件普遍支持，但 GCC 需要 -mcx16 才暴露 __GCC_HAVE_SYNC_COMPARE_AND_SWAP_16
+        # FreeStack128 (128-bit DWCAS) 依赖此宏判定可用性
+        if((CMAKE_SYSTEM_PROCESSOR MATCHES "(x86_64)|(AMD64)" OR
+            CMAKE_SYSTEM_PROCESSOR MATCHES "(i[3456]86)"))
+            target_compile_options(tfl_internal_flags INTERFACE -mcx16)
+        endif()
     elseif(CMAKE_CXX_COMPILER_ID MATCHES "MSVC")
         target_compile_options(tfl_internal_flags INTERFACE
             /W4 /Zc:preprocessor

taskflowlite/core/free_stack.hpp

@@ -1,4 +1,4 @@
-/// @file  free_stack.hpp
+/// @file  free_stack.hpp
 /// @brief 无锁侵入式栈 FreeStack —— Work 内存池的并发原语 (ABA-safe Treiber 栈)。
 /// @author wicyn
 /// @contact https://github.com/wicyn
@@ -21,86 +21,8 @@
 
 namespace tfl {
 
-namespace detail {
-
-// ============================================================================
-//  平台能力探测
-// ============================================================================
-
-// ---- HWASAN / ASAN 归一化 (GCC 用 __SANITIZE_*, Clang 用 __has_feature) --
-#if defined(__has_feature)
-#   if __has_feature(hwaddress_sanitizer)
-#       define TFL_HAS_HWASAN 1
-#   endif
-#   if __has_feature(address_sanitizer)
-#       define TFL_HAS_ASAN 1
-#   endif
-#endif
-#if defined(__SANITIZE_HWADDRESS__)
-#   define TFL_HAS_HWASAN 1
-#endif
-#if defined(__SANITIZE_ADDRESS__)
-#   define TFL_HAS_ASAN 1
-#endif
-
-/// @brief 平台是否必须用 128-bit (指针可能 > 48-bit 或高位被污染)。
-/// @details LA57 / LVA / HWASAN / ASAN / MTE / PAC 等会占用指针高位, 48-bit 打包不安全。
-inline constexpr bool kRequires128 =
-#if defined(TFL_PLATFORM_LA57)            || \
-    defined(TFL_PLATFORM_ARM64_LVA)       || \
-    defined(TFL_HAS_HWASAN)               || \
-    defined(TFL_HAS_ASAN)                 || \
-    defined(__ARM_FEATURE_MEMORY_TAGGING) || \
-    defined(__ARM_FEATURE_PAC_DEFAULT)
-    true
-#else
-    false
-#endif
-    ;
-
-/// @brief DWCAS 是否硬件可用 (编译期判定)。
-///
-/// @details 不依赖 std::atomic<16B>::is_always_lock_free —— 它在某些 ABI 下
-///          即使硬件支持也返回 false (libstdc++ 走 libatomic 路径)。
-///          直接看编译器宏更准。
-inline constexpr bool kHasLockFree128 =
-#if defined(__x86_64__) || defined(_M_X64)
-#if defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_16)
-    true
-#elif defined(_MSC_VER)
-    true
-#else
-    false
-#endif
-#elif defined(__aarch64__)
-#if defined(__ARM_FEATURE_ATOMICS)
-    true
-#else
-    false
-#endif
-#else
-        false
-#endif
-    ;
-
-
 // ============================================================================
-//  Tagged128 —— 16 字节 tagged pointer 布局
-// ============================================================================
-
-/// @brief 16 字节对齐的 tagged pointer (ptr 8B + tag 8B), 供 DWCAS 单指令比较。
-struct alignas(16) Tagged128 {
-    void*       ptr;
-    std::size_t tag;
-};
-static_assert(sizeof(Tagged128) == 16);
-static_assert(std::is_trivially_copyable_v<Tagged128>);
-
-}  // namespace detail
-
-
-// ============================================================================
-//  FreeStack128 —— 16 字节 tagged pointer 版本 (优先)
+//  FreeStack
 // ============================================================================
 
 /// @brief ABA-safe 无锁 LIFO 栈（128-bit tagged pointer DWCAS 实现）。
@@ -109,10 +31,10 @@ static_assert(std::is_trivially_copyable_v<Tagged128>);
 /// 需 x86-64 cmpxchg16b 或 ARM64 LSE CASP 硬件支持。整体 alignas(2*cache_line_size) 避免伪共享。
 ///
 /// @note chunk 处于 "storage available, no object" 状态，前 sizeof(void*) 字节可安全复用为链接指针。
-class alignas(cache_line_size * 2) FreeStack128 : public Immovable<FreeStack128> {
+class alignas(cache_line_size * 2) FreeStack : public Immovable<FreeStack> {
 public:
     /// @brief 构造空栈 —— 头指针置为 {nullptr, 0}。
-    FreeStack128() noexcept {
+    FreeStack() noexcept {
         m_head.store(Tagged{nullptr, 0}, std::memory_order_relaxed);
     }
 
@@ -151,154 +73,23 @@ class alignas(cache_line_size * 2) FreeStack128 : public Immovable<FreeStack128>
     }
 
 private:
-    using Tagged = detail::Tagged128;
-
-    /// @brief head 单独占一个 cache line, 避免与外部字段伪共享。
-    alignas(cache_line_size) std::atomic<Tagged> m_head;
-};
-
-
-// ============================================================================
-//  FreeStack48 —— 48-bit ptr + 16-bit tag 打包版本 (回退)
-// ============================================================================
-
-/// @brief ABA-safe 无锁 LIFO 栈（48-bit ptr + 16-bit tag 打包为 64-bit CAS）。
-///
-/// 单条 cmpxchg 完成，任何 x86-64/ARM64 均 always_lock_free，延迟更低。
-/// 仅适用于指针 <= 48-bit 的平台（非 LA57/LVA/HWASAN/ASAN/MTE/PAC）。
-///
-/// @note 2^16 tag 在 Work 池规模下不会触发 ABA 回卷。
-class alignas(cache_line_size * 2) FreeStack48 : public Immovable<FreeStack48> {
-public:
-    /// @brief 构造空栈 —— 头指针置为 0 (48-bit packed 表示)。
-    FreeStack48() noexcept {
-        m_head.store(0, std::memory_order_relaxed);
-    }
-
-    /// @brief 检查栈是否为空 (快照, 并发下可能立即过时)。
-    /// @return 头指针为 null 时返回 true。
-    [[nodiscard]] bool empty() const noexcept {
-        return Tagged::ptr_of(m_head.load(std::memory_order_relaxed)) == nullptr;
-    }
-
-    /// @brief 推入一个 chunk 到栈顶 (release-CAS)。
-    /// @param p 待推入 chunk 起始地址; 必须满足前提且地址 < 2^48。
-    TFL_FORCE_INLINE void push(void* p) noexcept {
-        std::uint64_t curr = m_head.load(std::memory_order_relaxed);
-        while (true) {
-            ChunkLink::store(p, Tagged::ptr_of(curr));
-            const std::uint64_t next = Tagged::pack(p, Tagged::tag_of(curr) + 1);
-            if (m_head.compare_exchange_weak(curr, next, std::memory_order_release, std::memory_order_relaxed)) {
-                return;
-            }
-            // CAS 失败: curr 已自动重载到最新值, 下轮重新链接重试
-        }
-    }
-
-    /// @brief 从栈顶弹出一个 chunk (acquire-CAS); 空则返回 nullptr。
-    /// @return chunk 起始地址, 或 nullptr (栈空)。
-    [[nodiscard]] TFL_FORCE_INLINE void* pop() noexcept {
-        std::uint64_t curr = m_head.load(std::memory_order_acquire);
-        while (true) {
-            void* top = Tagged::ptr_of(curr);
-            if (top == nullptr) return nullptr;
-            // top 可能已被别的线程 pop 后再 push 回来, ChunkLink::load
-            // 读到的 link 也许 "旧", 但 tag 不匹配会让 CAS 失败,
-            // 旧 link 不会污染 head —— ABA 由 tag 兜底
-            void* link = ChunkLink::load(top);
-            const std::uint64_t next = Tagged::pack(link, Tagged::tag_of(curr) + 1);
-            if (m_head.compare_exchange_weak(curr, next, std::memory_order_release, std::memory_order_acquire)) {
-                return top;
-            }
-        }
-    }
-
-private:
-    // ========================================================================
-    //  Tagged —— 48-bit ptr (低) | 16-bit tag (高) 打包/解包
-    // ========================================================================
-
-    /// @brief 把 (ptr, tag) 压成 64-bit, 绕过 16-byte DWCAS 的 ABI 依赖。
-    ///
-    /// @details 全部为 static 纯函数, Tagged 本身无状态 —— 仅作命名空间用, 无运行时开销。
-    struct Tagged {
-        /// @brief 容器总位宽 —— uint64_t 标准保证 64 位。
-        static constexpr unsigned TOTAL_BITS = sizeof(std::uint64_t) * char_bits;
-        /// @brief 平台契约: x86_64 / AArch64 用户态规范地址, 有效虚地址 <= 48 位。
-        /// 若未来需支持 LA57 / 52-bit AArch64, 改此处即可, TAG_BITS 自动收缩。
-        static constexpr unsigned PTR_BITS = 48;
-        static constexpr unsigned TAG_BITS = TOTAL_BITS - PTR_BITS;
 
-        static constexpr unsigned      TAG_SHIFT = PTR_BITS;
-        static constexpr std::uint64_t PTR_MASK  = (std::uint64_t{1} << PTR_BITS) - 1;
-        static constexpr std::uint64_t TAG_MASK  = ((std::uint64_t{1} << TAG_BITS) - 1) << TAG_SHIFT;
+    // ============================================================================
+    //  Tagged —— 16 字节 tagged pointer 布局
+    // ============================================================================
 
-        static_assert(TOTAL_BITS == 64, "Tagged depends on 64-bit uint64_t");
-        static_assert(PTR_BITS + TAG_BITS == TOTAL_BITS);
-        static_assert(PTR_BITS > 0 && TAG_BITS > 0);
-
-        /// @brief 从 64-bit 值中提取指针 (低 48 位)。
-        static void* ptr_of(std::uint64_t v) noexcept {
-            return reinterpret_cast<void*>(v & PTR_MASK);
-        }
-        /// @brief 从 64-bit 值中提取 tag (高 16 位)。
-        static std::uint64_t tag_of(std::uint64_t v) noexcept {
-            return v >> TAG_SHIFT;
-        }
-        /// @brief 打包 (ptr, tag) -> uint64_t。
-        /// @param p   必须在低 48 位 canonical 范围内。
-        /// @param tag 必须 < 2^16。
-        static std::uint64_t pack(void* p, std::uint64_t tag) noexcept {
-            const auto pi = reinterpret_cast<std::uintptr_t>(p);
-            assert((pi & ~PTR_MASK) == 0);                          ///< 指针契约检查
-            assert(tag < (std::uint64_t{1} << TAG_BITS));           ///< tag 越界对称检查
-            return (tag << TAG_SHIFT) | pi;
-        }
-        /// @brief 检查指针是否在低 48 位 canonical 范围内。
-        static bool is_canonical(void* p) noexcept {
-            return (reinterpret_cast<std::uintptr_t>(p) & ~PTR_MASK) == 0;
-        }
+    /// @brief 16 字节对齐的 tagged pointer (ptr 8B + tag 8B), 供 DWCAS 单指令比较。
+    struct alignas(16) Tagged {
+        void*       ptr;
+        std::size_t tag;
     };
+    static_assert(sizeof(Tagged) == 16);
+    static_assert(std::is_trivially_copyable_v<Tagged>);
 
-    static_assert(sizeof(void*) == 8, "FreeStack48 assumes 64-bit pointer (x86-64 / ARM64)");
-    static_assert(std::atomic<std::uint64_t>::is_always_lock_free, "FreeStack48 requires lock-free 8-byte atomics");
 
     /// @brief head 单独占一个 cache line, 避免与外部字段伪共享。
-    alignas(cache_line_size) std::atomic<std::uint64_t> m_head;
+    alignas(cache_line_size) std::atomic<Tagged> m_head;
 };
 
 
-// ============================================================================
-//  FreeStack —— 编译期平台选择
-// ============================================================================
-
-#if defined(TFL_FREESTACK_FORCE_128BIT) && defined(TFL_FREESTACK_FORCE_48BIT)
-#   error "TFL_FREESTACK_FORCE_128BIT and TFL_FREESTACK_FORCE_48BIT are mutually exclusive"
-#endif
-
-#if defined(TFL_FREESTACK_FORCE_128BIT)
-
-static_assert(detail::kHasLockFree128,
-              "TFL_FREESTACK_FORCE_128BIT requires hardware DWCAS support "
-              "(compile with -mcx16 / -march=armv8.1-a+lse / /arch:AVX)");
-using FreeStack = FreeStack128;
-
-#elif defined(TFL_FREESTACK_FORCE_48BIT)
-
-static_assert(!detail::kRequires128,
-              "TFL_FREESTACK_FORCE_48BIT is unsafe on this platform "
-              "(LA57 / LVA / HWASAN / MTE / PAC pollutes pointer high bits)");
-using FreeStack = FreeStack48;
-
-#else
-
-    static_assert(!(detail::kRequires128 && !detail::kHasLockFree128),
-        "Platform requires FreeStack128 (high pointer bits used) "
-        "but lock-free 128-bit CAS is unavailable on this target");
-
-    /// @brief 平台最优 FreeStack 别名: 128-bit CAS 可用时选 FreeStack128，否则回退 FreeStack48。
-    using FreeStack = std::conditional_t<detail::kRequires128 || detail::kHasLockFree128, FreeStack128, FreeStack48>;
-
-#endif
-
 }  // namespace tfl

taskflowlite/core/runtime.hpp

@@ -512,7 +512,7 @@ inline void Runtime::submit(Task task) {
 template <typename Gh>
     requires graph_holder<Gh>
 inline void Runtime::submit(Gh& gh) {
-    auto& graph = detail::to_graph(detail::unwrap(gh));
+    auto& graph = detail::to_graph(gh);
     if (graph.empty()) {
         return;
     }