perf: speed up tiny decoder

src/all_cases/all_cases.cc

@@ -47,7 +47,7 @@ void AllCases::build_data() { // find all cases
             uint32_t broken = check_case(head, basic_ranges[index]); // check and get broken address
             auto range_rev = Common::range_reverse(basic_ranges[index]); // reversed range
             if (broken) { // invalid case
-                auto delta = (uint32_t)1 << (32 - broken * 2); // this <--delta--> next possible range
+                auto delta = (uint32_t)1 << (32 - broken * 2); // this --delta--> next possible range
                 auto next_min = (range_rev & ~(delta - 1)) + delta;
                 while (Common::range_reverse(basic_ranges[++index]) < next_min); // located next range
                 --index;

src/all_cases/all_cases.h

@@ -18,11 +18,14 @@ public:
     static enum Status status();
     static const std::vector<uint32_t> (&fetch())[16];
 
+    // TODO: only for test
+    static int check_case(uint32_t head, uint32_t range);
+
 private:
     static bool available;
     static std::mutex building;
     static std::vector<uint32_t> data[16];
 
     static void build_data();
-    static int check_case(uint32_t head, uint32_t range);
+//    static int check_case(uint32_t head, uint32_t range);
 };

src/short_code/data_loader.cc

@@ -88,27 +88,43 @@ uint64_t ShortCode::tiny_decode_demo(uint32_t short_code) {
     uint32_t prefix = offset - RANGE_PREFIX_OFFSET_[head]; // range prefix
     short_code -= *offset;
 
-    uint32_t start_point = BASIC_RANGES_OFFSET_[prefix];
+    /// search target range
+    const auto &basic_ranges = BasicRanges::fetch();
+    for (auto index = BASIC_RANGES_OFFSET_[prefix]; index < basic_ranges.size(); ++index) {
 
-    printf("prefix: %X\n", prefix);
+        uint32_t range = basic_ranges[index]; // traverse basic ranges
-    printf("start at %d\n", start_point);
-    printf("next %d valid case\n", short_code);
 
-    uint32_t range;
+        uint32_t broken = AllCases::check_case(head, basic_ranges[index]); // check and get broken address
 
-    for (auto index = start_point; index < BasicRanges::fetch().size(); ++index) { // traverse basic ranges
+        auto range_rev = Common::range_reverse(basic_ranges[index]); // reversed range
-        range = BasicRanges::fetch()[index];
+
-        if (Common::check_case(head, range)) { // search for valid cases
+        if (broken) { // invalid case
+            auto delta = (uint32_t)1 << (32 - broken * 2); // this --delta--> next possible range
+            auto next_min = (range_rev & ~(delta - 1)) + delta;
+            while (Common::range_reverse(basic_ranges[++index]) < next_min); // located next range
+            --index;
+        } else {
 
             if (!short_code--) { // short code approximate
-                break; // found target range
-            }
 
-        }
+                /// found target range
+                return head << 32 | range_rev;
+
             }
 
-    printf("range -> %08X\n", Common::range_reverse(range));
+        }
 
-    return (uint64_t)head << 32 | Common::range_reverse(range);
+//        if (Common::check_case(head, range)) { // search for valid cases
+//
+//            if (!short_code--) { // short code approximate
+//
+//                /// found target range
+//                return head << 32 | Common::range_reverse(range);
+//
+//            }
+//
+//        }
+    }
 
+    return 0; // never reach when input valid
 }