From a5f2ffa9513b964e3dee6610bca397adb09be479 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?L=C5=91rinc?= <pap.lorinc@gmail.com>
Date: Tue, 22 Apr 2025 13:00:34 +0200
Subject: [PATCH] refactor: extract `PREVECTOR_SIZE` to header constant

Co-authored-by: Luke Dashjr <luke-jr+git@utopios.org>
Co-authored-by: kuegi <29012906+kuegi@users.noreply.github.com>
---
 src/bench/checkqueue.cpp |  2 +-
 src/bench/prevector.cpp  | 41 +++++++++++++++++++++-------------------
 src/script/script.h      |  3 ++-
 3 files changed, 25 insertions(+), 21 deletions(-)

diff --git a/src/bench/checkqueue.cpp b/src/bench/checkqueue.cpp
index 8134154eb11..7423601a6f4 100644
--- a/src/bench/checkqueue.cpp
+++ b/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,
diff --git a/src/bench/prevector.cpp b/src/bench/prevector.cpp
index 60c43e86e1b..f4c5d163689 100644
--- a/src/bench/prevector.cpp
+++ b/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<28, T> t1;
-        t0.resize(28);
-        t1.resize(29);
+        prevector<PREVECTOR_SIZE, T> t0;
+        prevector<PREVECTOR_SIZE, T> t1;
+        t0.resize(PREVECTOR_SIZE);
+        t1.resize(PREVECTOR_SIZE + 1);
     });
 }
 
 template <typename T>
 static void PrevectorClear(benchmark::Bench& bench)
 {
-    prevector<28, T> t0;
-    prevector<28, T> t1;
+    prevector<PREVECTOR_SIZE, T> t0;
+    prevector<PREVECTOR_SIZE, T> t1;
     bench.batch(2).run([&] {
-        t0.resize(28);
+        t0.resize(PREVECTOR_SIZE);
         t0.clear();
-        t1.resize(29);
+        t1.resize(PREVECTOR_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<28, T> t1;
+    prevector<PREVECTOR_SIZE, T> t0;
+    prevector<PREVECTOR_SIZE, T> t1;
     bench.batch(4).run([&] {
-        t0.resize(28);
+        t0.resize(PREVECTOR_SIZE);
         t0.resize(0);
-        t1.resize(29);
+        t1.resize(PREVECTOR_SIZE + 1);
         t1.resize(0);
     });
 }
@@ -64,8 +67,8 @@ template <typename T>
 static void PrevectorDeserialize(benchmark::Bench& bench)
 {
     DataStream s0{};
-    prevector<28, T> t0;
-    t0.resize(28);
+    prevector<PREVECTOR_SIZE, T> t0;
+    t0.resize(PREVECTOR_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<PREVECTOR_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<PREVECTOR_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<PREVECTOR_SIZE, T>> vec;
         vec.reserve(260);
         for (size_t i = 0; i < 260; ++i) {
             // force allocation
-            vec.emplace_back(29, T{});
+            vec.emplace_back(PREVECTOR_SIZE + 1, T{});
         }
     });
 }
diff --git a/src/script/script.h b/src/script/script.h
index f4579849803..83c9461952e 100644
--- a/src/script/script.h
+++ b/src/script/script.h
@@ -406,7 +406,8 @@ private:
  * Tests in October 2015 showed use of this reduced dbcache memory usage by 23%
  *  and made an initial sync 13% faster.
  */
-typedef prevector<28, unsigned char> CScriptBase;
+static constexpr unsigned int PREVECTOR_SIZE{28};
+typedef prevector<PREVECTOR_SIZE, unsigned char> CScriptBase;
 
 bool GetScriptOp(CScriptBase::const_iterator& pc, CScriptBase::const_iterator end, opcodetype& opcodeRet, std::vector<unsigned char>* pvchRet);