refactor: extract STATIC_SIZE constant to prevector

Co-authored-by: Anthony Towns <aj@erisian.com.au>

src/bench/checkqueue.cpp

@@ -8,6 +8,7 @@
 #include <key.h>
 #include <prevector.h>
 #include <random.h>
+#include <script/script.h>
 
 #include <cstddef>
 #include <cstdint>
@@ -16,7 +17,6 @@
 
 static const size_t BATCHES = 101;
 static const size_t BATCH_SIZE = 30;
-static const int PREVECTOR_SIZE = 28;
 static const unsigned int QUEUE_BATCH_SIZE = 128;
 
 // This Benchmark tests the CheckQueue with a slightly realistic workload,
@@ -30,9 +30,9 @@ static void CCheckQueueSpeedPrevectorJob(benchmark::Bench& bench)
     ECC_Context ecc_context{};
 
     struct PrevectorJob {
-        prevector<PREVECTOR_SIZE, uint8_t> p;
+        prevector<CScriptBase::STATIC_SIZE, uint8_t> p;
         explicit PrevectorJob(FastRandomContext& insecure_rand){
-            p.resize(insecure_rand.randrange(PREVECTOR_SIZE*2));
+            p.resize(insecure_rand.randrange(CScriptBase::STATIC_SIZE * 2));
         }
         std::optional<int> operator()()
         {

src/bench/prevector.cpp

@@ -5,17 +5,20 @@
 #include <prevector.h>
 
 #include <bench/bench.h>
+#include <script/script.h>
 #include <serialize.h>
 #include <streams.h>
 
 #include <type_traits>
 #include <vector>
 
-struct nontrivial_t {
+struct nontrivial_t
+{
     int x{-1};
     nontrivial_t() = default;
     SERIALIZE_METHODS(nontrivial_t, obj) { READWRITE(obj.x); }
 };
+
 static_assert(!std::is_trivially_default_constructible_v<nontrivial_t>,
               "expected nontrivial_t to not be trivially constructible");
 
@@ -27,22 +30,22 @@ template <typename T>
 static void PrevectorDestructor(benchmark::Bench& bench)
 {
     bench.batch(2).run([&] {
-        prevector<28, T> t0;
+        prevector<CScriptBase::STATIC_SIZE, T> t0;
-        prevector<28, T> t1;
+        prevector<CScriptBase::STATIC_SIZE, T> t1;
-        t0.resize(28);
+        t0.resize(CScriptBase::STATIC_SIZE);
-        t1.resize(29);
+        t1.resize(CScriptBase::STATIC_SIZE + 1);
     });
 }
 
 template <typename T>
 static void PrevectorClear(benchmark::Bench& bench)
 {
-    prevector<28, T> t0;
+    prevector<CScriptBase::STATIC_SIZE, T> t0;
-    prevector<28, T> t1;
+    prevector<CScriptBase::STATIC_SIZE, T> t1;
     bench.batch(2).run([&] {
-        t0.resize(28);
+        t0.resize(CScriptBase::STATIC_SIZE);
         t0.clear();
-        t1.resize(29);
+        t1.resize(CScriptBase::STATIC_SIZE + 1);
         t1.clear();
     });
 }
@@ -50,12 +53,12 @@ static void PrevectorClear(benchmark::Bench& bench)
 template <typename T>
 static void PrevectorResize(benchmark::Bench& bench)
 {
-    prevector<28, T> t0;
+    prevector<CScriptBase::STATIC_SIZE, T> t0;
-    prevector<28, T> t1;
+    prevector<CScriptBase::STATIC_SIZE, T> t1;
     bench.batch(4).run([&] {
-        t0.resize(28);
+        t0.resize(CScriptBase::STATIC_SIZE);
         t0.resize(0);
-        t1.resize(29);
+        t1.resize(CScriptBase::STATIC_SIZE + 1);
         t1.resize(0);
     });
 }
@@ -64,8 +67,8 @@ template <typename T>
 static void PrevectorDeserialize(benchmark::Bench& bench)
 {
     DataStream s0{};
-    prevector<28, T> t0;
+    prevector<CScriptBase::STATIC_SIZE, T> t0;
-    t0.resize(28);
+    t0.resize(CScriptBase::STATIC_SIZE);
     for (auto x = 0; x < 900; ++x) {
         s0 << t0;
     }
@@ -74,7 +77,7 @@ static void PrevectorDeserialize(benchmark::Bench& bench)
         s0 << t0;
     }
     bench.batch(1000).run([&] {
-        prevector<28, T> t1;
+        prevector<CScriptBase::STATIC_SIZE, T> t1;
         for (auto x = 0; x < 1000; ++x) {
             s0 >> t1;
         }
@@ -86,7 +89,7 @@ template <typename T>
 static void PrevectorFillVectorDirect(benchmark::Bench& bench)
 {
     bench.run([&] {
-        std::vector<prevector<28, T>> vec;
+        std::vector<prevector<CScriptBase::STATIC_SIZE, T>> vec;
         vec.reserve(260);
         for (size_t i = 0; i < 260; ++i) {
             vec.emplace_back();
@@ -99,11 +102,11 @@ template <typename T>
 static void PrevectorFillVectorIndirect(benchmark::Bench& bench)
 {
     bench.run([&] {
-        std::vector<prevector<28, T>> vec;
+        std::vector<prevector<CScriptBase::STATIC_SIZE, T>> vec;
         vec.reserve(260);
         for (size_t i = 0; i < 260; ++i) {
             // force allocation
-            vec.emplace_back(29, T{});
+            vec.emplace_back(CScriptBase::STATIC_SIZE + 1, T{});
         }
     });
 }

src/prevector.h

@@ -38,6 +38,8 @@ class prevector {
     static_assert(std::is_trivially_copyable_v<T>);
 
 public:
+    static constexpr unsigned int STATIC_SIZE{N};
+
     typedef Size size_type;
     typedef Diff difference_type;
     typedef T value_type;