PPTC & Pool Enhancements. (#1968)

* PPTC & Pool Enhancements.

* Avoid buffer allocations in CodeGenContext.GetCode(). Avoid stream allocations in PTC.PtcInfo.

Refactoring/nits.

* Use XXHash128, for Ptc.Load & Ptc.Save, x10 faster than Md5.

* Why not a nice Span.

* Added a simple PtcFormatter library for deserialization/serialization, which does not require reflection, in use at PtcJumpTable and PtcProfiler; improves maintainability and simplicity/readability of affected code.

* Nits.

* Revert #1987.

* Revert "Revert #1987."

This reverts commit 998be765cf7f7da5ff0c1c08de704c9012b0f49c.

1 files changed, 101 insertions, 23 deletions

diff --git a/ARMeilleure/Common/ThreadStaticPool.cs b/ARMeilleure/Common/ThreadStaticPool.cs
index e23bf1dc..bbe662f8 100644
--- a/ARMeilleure/Common/ThreadStaticPool.cs
+++ b/ARMeilleure/Common/ThreadStaticPool.cs
@@ -1,4 +1,5 @@
-using System;
+using ARMeilleure.Translation.PTC;
+using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
 
@@ -6,9 +7,6 @@ namespace ARMeilleure.Common
 {
     class ThreadStaticPool<T> where T : class, new()
     {
-        private const int ChunkSizeLimit = 1000; // even
-        private const int PoolSizeIncrement = 200; // > 0
-
         [ThreadStatic]
         private static ThreadStaticPool<T> _instance;
 
@@ -18,21 +16,36 @@ namespace ARMeilleure.Common
             {
                 if (_instance == null)
                 {
-                    PreparePool(0); // So that we can still use a pool when blindly initializing one.
+                    PreparePool(); // So that we can still use a pool when blindly initializing one.
                 }
 
                 return _instance;
             }
         }
 
-        private static ConcurrentDictionary<int, Stack<ThreadStaticPool<T>>> _pools = new();
+        private static readonly ConcurrentDictionary<int, Stack<ThreadStaticPool<T>>> _pools = new();
 
         private static Stack<ThreadStaticPool<T>> GetPools(int groupId)
         {
             return _pools.GetOrAdd(groupId, (groupId) => new());
         }
 
-        public static void PreparePool(int groupId)
+        public static void PreparePool(
+            int groupId = 0,
+            ChunkSizeLimit chunkSizeLimit = ChunkSizeLimit.Large,
+            PoolSizeIncrement poolSizeIncrement = PoolSizeIncrement.Default)
+        {
+            if (Ptc.State == PtcState.Disabled)
+            {
+                PreparePoolDefault(groupId, (int)chunkSizeLimit, (int)poolSizeIncrement);
+            }
+            else
+            {
+                PreparePoolSlim((int)chunkSizeLimit, (int)poolSizeIncrement);
+            }
+        }
+
+        private static void PreparePoolDefault(int groupId, int chunkSizeLimit, int poolSizeIncrement)
         {
             // Prepare the pool for this thread, ideally using an existing one from the specified group.
 
@@ -41,27 +54,75 @@ namespace ARMeilleure.Common
                 var pools = GetPools(groupId);
                 lock (pools)
                 {
-                    _instance = (pools.Count != 0) ? pools.Pop() : new();
+                    _instance = (pools.Count != 0) ? pools.Pop() : new(chunkSizeLimit, poolSizeIncrement);
                 }
             }
         }
 
-        public static void ReturnPool(int groupId)
+        private static void PreparePoolSlim(int chunkSizeLimit, int poolSizeIncrement)
+        {
+            // Prepare the pool for this thread.
+
+            if (_instance == null)
+            {
+                _instance = new(chunkSizeLimit, poolSizeIncrement);
+            }
+        }
+
+        public static void ResetPool(int groupId = 0)
+        {
+            if (Ptc.State == PtcState.Disabled)
+            {
+                ResetPoolDefault(groupId);
+            }
+            else
+            {
+                ResetPoolSlim();
+            }
+        }
+
+        private static void ResetPoolDefault(int groupId)
         {
             // Reset, limit if necessary, and return the pool for this thread to the specified group.
 
-            var pools = GetPools(groupId);
-            lock (pools)
+            if (_instance != null)
+            {
+                var pools = GetPools(groupId);
+                lock (pools)
+                {
+                    _instance.Clear();
+                    _instance.ChunkSizeLimiter();
+                    pools.Push(_instance);
+
+                    _instance = null;
+                }
+            }
+        }
+
+        private static void ResetPoolSlim()
+        {
+            // Reset, limit if necessary, the pool for this thread.
+
+            if (_instance != null)
             {
                 _instance.Clear();
                 _instance.ChunkSizeLimiter();
-                pools.Push(_instance);
+            }
+        }
 
-                _instance = null;
+        public static void DisposePools()
+        {
+            if (Ptc.State == PtcState.Disabled)
+            {
+                DisposePoolsDefault();
+            }
+            else
+            {
+                DisposePoolSlim();
             }
         }
 
-        public static void ResetPools()
+        private static void DisposePoolsDefault()
         {
             // Resets any static references to the pools used by threads for each group, allowing them to be garbage collected.
 
@@ -78,20 +139,37 @@ namespace ARMeilleure.Common
             _pools.Clear();
         }
 
+        private static void DisposePoolSlim()
+        {
+            // Dispose the pool for this thread.
+
+            if (_instance != null)
+            {
+                _instance.Dispose();
+
+                _instance = null;
+            }
+        }
+
         private List<T[]> _pool;
         private int _chunkIndex = -1;
         private int _poolIndex = -1;
+        private int _chunkSizeLimit;
+        private int _poolSizeIncrement;
 
-        private ThreadStaticPool()
+        private ThreadStaticPool(int chunkSizeLimit, int poolSizeIncrement)
         {
-            _pool = new(ChunkSizeLimit * 2);
+            _chunkSizeLimit = chunkSizeLimit;
+            _poolSizeIncrement = poolSizeIncrement;
+
+            _pool = new(chunkSizeLimit * 2);
 
             AddChunkIfNeeded();
         }
 
         public T Allocate()
         {
-            if (++_poolIndex >= PoolSizeIncrement)
+            if (++_poolIndex >= _poolSizeIncrement)
             {
                 AddChunkIfNeeded();
 
@@ -105,9 +183,9 @@ namespace ARMeilleure.Common
         {
             if (++_chunkIndex >= _pool.Count)
             {
-                T[] pool = new T[PoolSizeIncrement];
+                T[] pool = new T[_poolSizeIncrement];
 
-                for (int i = 0; i < PoolSizeIncrement; i++)
+                for (int i = 0; i < _poolSizeIncrement; i++)
                 {
                     pool[i] = new T();
                 }
@@ -124,18 +202,18 @@ namespace ARMeilleure.Common
 
         private void ChunkSizeLimiter()
         {
-            if (_pool.Count >= ChunkSizeLimit)
+            if (_pool.Count >= _chunkSizeLimit)
             {
-                int newChunkSize = ChunkSizeLimit / 2;
+                int newChunkSize = _chunkSizeLimit / 2;
 
                 _pool.RemoveRange(newChunkSize, _pool.Count - newChunkSize);
-                _pool.Capacity = ChunkSizeLimit * 2;
+                _pool.Capacity = _chunkSizeLimit * 2;
             }
         }
 
         private void Dispose()
         {
-            _pool.Clear();
+            _pool = null;
         }
     }
 }