feat: add AllCases module

src/core/CMakeLists.txt

@@ -6,4 +6,6 @@ project(klotski-core VERSION 0.1.2 LANGUAGES CXX)
 
 add_compile_options(-fno-exceptions)
 
+include_directories(utils)
+
 add_executable(${PROJECT_NAME} main.cc all_cases/basic_ranges.cc all_cases/all_cases.cc)

src/core/all_cases/all_cases.cc

@@ -1,21 +1,22 @@
-#include <iostream>
-
-#include "reverse.h"
+#include "utility.h"
 #include "all_cases.h"
 
-//typedef uint32_t Range;
-
-using klotski::cases::BasicRanges;
-using klotski::cases::range_reverse;
+namespace klotski {
+namespace cases {
 
-inline int low_zero_num(uint32_t bin) {
-    return __builtin_ctzl(bin);
-
-    // WARN: be aware of serious performance issues
-    // return __builtin_popcount(~(bin ^ -bin)) - 1;
+/// Calculate all possible klotski heads.
+static consteval std::array<int, 12> case_heads() {
+    std::array<int, 12> heads = {};
+    for (int i = 0, head = 0; head < 15; ++head) {
+        if (head % 4 != 3) {
+            heads[i++] = head;
+        }
+    }
+    return heads;
 }
 
-int check_range(int head, uint32_t range) noexcept {
+/// Check whether the combination of head and range is valid.
+static int check_range(int head, uint32_t range) noexcept {
     constexpr uint32_t MASK_1x1 = 0b00000001;
     constexpr uint32_t MASK_1x2 = 0b00000011;
     constexpr uint32_t MASK_2x1 = 0b00010001;
@@ -48,69 +49,59 @@ int check_range(int head, uint32_t range) noexcept {
     return 0; // pass check
 }
 
-void demo() {
-
-//    std::cout << __builtin_popcount(~(6 ^ -6)) - 1 << std::endl;
-//    return;
-
-    constexpr std::array<int, 12> heads = {
-        0x0, 0x1, 0x2,
-        0x4, 0x5, 0x6,
-        0x8, 0x9, 0xA,
-        0xC, 0xD, 0xE,
-    };
-
-    auto num = 0;
-
-    std::array<std::vector<uint32_t>, 16> data;
-
-    // TODO: vector reserve
-
-    auto basic_ranges = BasicRanges::Instance().Fetch();
-
-//    std::vector<uint32_t> reversed {basic_ranges.begin(), basic_ranges.end()};
-//    for (auto &x : reversed) {
-//        x = range_reverse(x);
-//    }
-
-    for (auto head : heads) {
-        for (uint32_t index = 0; index < basic_ranges.size(); ++index) {
-            auto offset = check_range(head, basic_ranges[index]);
-            if (offset) { // invalid case
-                auto tmp = (uint32_t)0b1 << (32 - offset * 2); // distance to next possible range
-                ///         !! <- broken
-                /// ( xx xx xx ) xx xx xx ... [reversed range]
-                ///         +1   00 00 00 ...     (delta)
-                tmp += range_reverse(basic_ranges[index]) & ~(tmp - 1);
-                while (range_reverse(basic_ranges[++index]) < tmp); // located next range
-                --index;
-
-//                next += reversed[index] & ~(next - 1);
-//                auto kk = std::lower_bound(reversed.begin() + index, reversed.end(), next);
-//                index = kk - reversed.begin() - 1;
-
-                continue;
-            }
-
-            data[head].emplace_back(range_reverse(basic_ranges[index]));
-
-//            ++index;
-
-            ++num;
-//            volatile auto r = range_reverse(basic_ranges[index]); // release valid cases
+/// Build all valid ranges of the specified head.
+void AllCases::BuildCases(int head, Ranges &basic_ranges, Ranges &release) noexcept {
+    release.reserve(ALL_CASES_NUM[head]);
+    for (uint32_t index = 0; index < basic_ranges.size(); ++index) {
+        auto offset = check_range(head, basic_ranges[index]);
+        if (offset) { // invalid case
+            auto tmp = (uint32_t)0b1 << (32 - offset * 2); // distance to next possible range
+            ///         !! <- broken
+            /// ( xx xx xx ) xx xx xx ... [reversed range]
+            ///         +1   00 00 00 ...     (delta)
+            tmp += range_reverse(basic_ranges[index]) & ~(tmp - 1);
+            while (range_reverse(basic_ranges[++index]) < tmp); // located next range
+            --index;
+            continue;
         }
+        release.emplace_back(range_reverse(basic_ranges[index])); // release valid case
     }
+}
 
-//    for (auto &x : data) {
-//        std::cout << x.size() << std::endl;
-//    }
-
-    for (uint64_t head = 0; head < 15; ++head) {
-        for (auto x : data[head]) {
-            printf("%09llX\n", (head << 32) | x);
+void AllCases::Build() noexcept {
+    if (available_) { // data already available
+        return;
+    }
+    if (building_.try_lock()) { // mutex lock success
+        if (available_) {
+            building_.unlock();
+            return;
+        }
+        auto basic_ranges = BasicRanges::Instance().Fetch();
+        for (auto head : case_heads()) {
+            BuildCases(head, basic_ranges, GetCases()[head]);
         }
+        available_ = true;
+    } else {
+        building_.lock(); // blocking waiting
     }
+    building_.unlock(); // release mutex
+}
 
-//    std::cout << num << std::endl;
+AllRanges& AllCases::GetCases() noexcept {
+    static std::array<Ranges, 16> cases;
+    return cases;
+}
 
+AllCases& AllCases::Instance() noexcept {
+    static AllCases instance;
+    return instance;
 }
+
+AllRanges& AllCases::Fetch() noexcept {
+    this->Build();
+    return GetCases();
+}
+
+} // namespace cases
+} // namespace klotski

src/core/all_cases/all_cases.h

@@ -38,20 +38,31 @@
 #include <mutex>
 #include <vector>
 #include <cstdint>
-
-void demo();
+#include <numeric>
 
 namespace klotski {
 namespace cases {
 
 typedef uint32_t Range;
 typedef std::vector<Range> Ranges;
+typedef std::array<Ranges, 16> AllRanges;
+
+constexpr auto BASIC_RANGES_NUM = 7311921;
+
+constexpr std::array<int, 16> ALL_CASES_NUM {
+    2942906, 2260392, 2942906, 0,
+    2322050, 1876945, 2322050, 0,
+    2322050, 1876945, 2322050, 0,
+    2942906, 2260392, 2942906, 0,
+};
 
-const auto BASIC_RANGES_NUM = 7311921;
+constexpr auto ALL_CASES_NUM_ = std::accumulate(
+    ALL_CASES_NUM.begin(), ALL_CASES_NUM.end(), 0
+);
 
 class BasicRanges {
 public:
-    void Build();
+    void Build() noexcept;
     const Ranges& Fetch() noexcept;
     bool IsAvailable() const noexcept;
 
@@ -68,9 +79,29 @@ private:
 
     BasicRanges() = default;
     static Ranges& GetRanges() noexcept;
-    static void BuildRanges(Ranges &ranges);
-    static void SpawnRanges(Ranges&, int, int, int, int) noexcept;
+    static void BuildRanges(Ranges &ranges) noexcept;
+    static void SpawnRanges(Ranges &ranges, int, int, int, int) noexcept;
+};
+
+class AllCases {
+public:
+
+//    void Build();
+
+    void Build() noexcept;
+    AllRanges& Fetch() noexcept;
+
+    static AllCases& Instance() noexcept;
+
+private:
+    std::mutex building_;
+    bool available_ = false;
+
+    static AllRanges& GetCases() noexcept;
+    static void BuildCases(int head, Ranges &basic_ranges, Ranges &release) noexcept;
 };
 
+void demo();
+
 } // namespace cases
 } // namespace klotski

src/core/all_cases/basic_ranges.cc

@@ -1,7 +1,7 @@
 #include <list>
 #include <algorithm>
 
-#include "reverse.h"
+#include "utility.h"
 #include "all_cases.h"
 
 namespace klotski {
@@ -61,7 +61,7 @@ void BasicRanges::SpawnRanges(Ranges &ranges, int n1, int n2, int n3, int n4) no
 }
 
 /// Search and sort all possible basic-ranges permutations.
-void BasicRanges::BuildRanges(Ranges &ranges) {
+void BasicRanges::BuildRanges(Ranges &ranges) noexcept {
     ranges.clear();
     ranges.reserve(BASIC_RANGES_NUM);
     std::list<RangeIter> flags {ranges.begin()}; // mark ordered interval
@@ -85,16 +85,21 @@ void BasicRanges::BuildRanges(Ranges &ranges) {
 }
 
 /// Execute the build process and ensure thread safety.
-void BasicRanges::Build() {
-    if (!available_) {
-        if (building_.try_lock()) { // mutex lock success
-            BuildRanges(GetRanges());
-            available_ = true;
-        } else {
-            building_.lock(); // blocking waiting
+void BasicRanges::Build() noexcept {
+    if (available_) {
+        return; // reduce consumption of mutex
+    }
+    if (building_.try_lock()) { // mutex lock success
+        if (available_) {
+            building_.unlock();
+            return;
         }
-        building_.unlock(); // release mutex
+        BuildRanges(GetRanges());
+        available_ = true;
+    } else {
+        building_.lock(); // blocking waiting
     }
+    building_.unlock(); // release mutex
 }
 
 Ranges& BasicRanges::GetRanges() noexcept {
@@ -108,7 +113,7 @@ BasicRanges& BasicRanges::Instance() noexcept {
 }
 
 const Ranges& BasicRanges::Fetch() noexcept {
-    Build();
+    this->Build();
     return GetRanges();
 }
 

src/core/main.cc

@@ -2,6 +2,7 @@
 
 #include "all_cases/all_cases.h"
 
+using klotski::cases::AllCases;
 using klotski::cases::BasicRanges;
 
 int main() {
@@ -10,8 +11,6 @@ int main() {
 
     auto start = clock();
 
-    demo();
-
 //    std::cout << BasicRanges::Instance().IsAvailable() << std::endl;
 //    BasicRanges::Instance().Build();
 //    std::cout << BasicRanges::Instance().IsAvailable() << std::endl;
@@ -19,6 +18,13 @@ int main() {
 //        printf("%08X\n", x);
 //    }
 
+    AllCases::Instance().Build();
+    for (uint64_t head = 0; head < 15; ++head) {
+        for (auto range : AllCases::Instance().Fetch()[head]) {
+            printf("%09llX\n", head << 32 | range);
+        }
+    }
+
     std::cerr << ((clock() - start) * 1000 / CLOCKS_PER_SEC) << "ms" << std::endl;
 
     return 0;

src/core/all_cases/reverse.h → src/core/utils/utility.h

@@ -1,7 +1,15 @@
 #pragma once
 
+#include <cstdint>
+
 namespace klotski {
-namespace cases {
+
+inline int low_zero_num(uint32_t bin) {
+    return __builtin_ctzl(bin);
+
+    // WARN: be aware of serious performance issues
+    // return __builtin_popcount(~(bin ^ -bin)) - 1;
+}
 
 inline uint32_t range_reverse(uint32_t bin) noexcept {
 #if defined(__GNUC__) || defined(__clang__)
@@ -16,5 +24,4 @@ inline uint32_t range_reverse(uint32_t bin) noexcept {
     return ((bin << 2) & 0xCCCCCCCC) | ((bin >> 2) & 0x33333333);
 }
 
-} // namespace cases
 } // namespace klotski