From a15270b6b50357032b0257d82e9c31c0f5061d00 Mon Sep 17 00:00:00 2001
From: Brett <brettmaster1@gmail.com>
Date: Fri, 2 May 2025 00:15:31 -0400
Subject: [PATCH] forward

---
 .idea/editor.xml        |   2 +
 CMakeLists.txt          |   2 +-
 include/blt/gp/fwdecl.h |   9 ++
 include/blt/gp/tree.h   | 180 ++++++++++++++++------------------------
 src/program.cpp         |   4 +-
 src/tree.cpp            |  75 +++++++++++++++--
 6 files changed, 152 insertions(+), 120 deletions(-)

diff --git a/.idea/editor.xml b/.idea/editor.xml
index a8c6caa..eb7507a 100644
--- a/.idea/editor.xml
+++ b/.idea/editor.xml
@@ -7,6 +7,8 @@
     <option name="/Default/CodeInspection/Highlighting/InspectionSeverities/=CppRedundantFwdClassOrEnumSpecifier/@EntryIndexedValue" value="SUGGESTION" type="string" />
     <option name="/Default/CodeInspection/Highlighting/InspectionSeverities/=CppRedundantQualifierADL/@EntryIndexedValue" value="DO_NOT_SHOW" type="string" />
     <option name="/Default/CodeInspection/Highlighting/InspectionSeverities/=CppTooWideScopeInitStatement/@EntryIndexedValue" value="DO_NOT_SHOW" type="string" />
+    <option name="/Default/CodeStyle/Generate/=CppDefinitions/@KeyIndexDefined" value="true" type="bool" />
+    <option name="/Default/CodeStyle/Generate/=CppDefinitions/Options/=GenerateInlineDefinitions/@EntryIndexedValue" value="False" type="string" />
     <option name="/Default/CodeStyle/Naming/CppNaming/Rules/=Class_0020and_0020struct_0020fields/@EntryIndexedValue" value="&lt;NamingElement Priority=&quot;11&quot;&gt;&lt;Descriptor Static=&quot;Indeterminate&quot; Constexpr=&quot;Indeterminate&quot; Const=&quot;Indeterminate&quot; Volatile=&quot;Indeterminate&quot; Accessibility=&quot;NOT_APPLICABLE&quot;&gt;&lt;type Name=&quot;class field&quot; /&gt;&lt;type Name=&quot;struct field&quot; /&gt;&lt;/Descriptor&gt;&lt;Policy Inspect=&quot;True&quot; WarnAboutPrefixesAndSuffixes=&quot;False&quot; Prefix=&quot;m_&quot; Suffix=&quot;&quot; Style=&quot;aa_bb&quot; /&gt;&lt;/NamingElement&gt;" type="string" />
     <option name="/Default/CodeStyle/Naming/CppNaming/Rules/=Enums/@EntryIndexedValue" value="&lt;NamingElement Priority=&quot;3&quot;&gt;&lt;Descriptor Static=&quot;Indeterminate&quot; Constexpr=&quot;Indeterminate&quot; Const=&quot;Indeterminate&quot; Volatile=&quot;Indeterminate&quot; Accessibility=&quot;NOT_APPLICABLE&quot;&gt;&lt;type Name=&quot;enum&quot; /&gt;&lt;/Descriptor&gt;&lt;Policy Inspect=&quot;True&quot; WarnAboutPrefixesAndSuffixes=&quot;False&quot; Prefix=&quot;&quot; Suffix=&quot;&quot; Style=&quot;AA_BB&quot; /&gt;&lt;/NamingElement&gt;" type="string" />
   </component>
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6313ebd..7c22918 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -27,7 +27,7 @@ macro(compile_options target_name)
     sanitizers(${target_name})
 endmacro()
 
-project(blt-gp VERSION 0.5.27)
+project(blt-gp VERSION 0.5.28)
 
 include(CTest)
 
diff --git a/include/blt/gp/fwdecl.h b/include/blt/gp/fwdecl.h
index 40ee4ad..2162fff 100644
--- a/include/blt/gp/fwdecl.h
+++ b/include/blt/gp/fwdecl.h
@@ -43,6 +43,15 @@ namespace blt::gp
     struct op_container_t;
     
     class evaluation_context;
+
+    template <typename T>
+    class evaluation_ref;
+
+    class tree_manipulator_t;
+
+    class single_operation_tree_manipulator_t;
+
+    class multi_operation_tree_manipulator_t;
     
     class tree_t;
     
diff --git a/include/blt/gp/tree.h b/include/blt/gp/tree.h
index 3d6eb44..c11b51f 100644
--- a/include/blt/gp/tree.h
+++ b/include/blt/gp/tree.h
@@ -97,15 +97,14 @@ namespace blt::gp
         operator_special_flags m_flags;
     };
 
-    class evaluation_context
-    {
-    public:
-        explicit evaluation_context() = default;
-
-        stack_allocator values;
-    };
-
-    inline size_t accumulate_type_sizes(const detail::op_iter_t begin, const detail::op_iter_t end)
+    /**
+     * Calculate the number of bytes stored inside the tree's stack between the begin and end iterators
+     *
+     * @param begin Begin iterator to the container storing the tree's operators
+     * @param end End iterator
+     * @return bytes used by operators between [begin, end)
+     */
+    inline size_t calculate_ephemeral_size(const detail::op_iter_t begin, const detail::op_iter_t end)
     {
         size_t total = 0;
         for (auto it = begin; it != end; ++it)
@@ -116,6 +115,21 @@ namespace blt::gp
         return total;
     }
 
+    /**
+     * Stores the stack used to evaluate a tree. This is done such that executing a tree doesn't modify the internal stack
+     */
+    class evaluation_context
+    {
+    public:
+        explicit evaluation_context() = default;
+
+        stack_allocator values;
+    };
+
+    /**
+     * Provides a method for accessing an evaluated tree's returned type;
+     * this class ensures that the drop function is properly called for the evaluation context
+     */
     template <typename T>
     class evaluation_ref
     {
@@ -185,8 +199,54 @@ namespace blt::gp
         evaluation_context* m_context;
     };
 
+    struct temporary_tree_storage_t
+    {
+        explicit temporary_tree_storage_t(tree_t& tree);
+
+        temporary_tree_storage_t(tracked_vector<op_container_t>& operations, stack_allocator& values): operations(&operations), values(&values)
+        {
+        }
+
+        void clear() const
+        {
+            operations->clear();
+            values->reset();
+        }
+
+        tracked_vector<op_container_t>* operations;
+        stack_allocator* values;
+    };
+
+    class single_operation_tree_manipulator_t
+    {
+    };
+
+    class multi_operation_tree_manipulator_t
+    {
+    };
+
+    /**
+     * This is the parent class responsible for managing a tree's internal state at runtime.
+     * While it is possible to create a tree without a need for this class, you should not attempt to modify a tree's internal state after creation.
+     * This class provides helper methods to ensure that a tree remains well-ordered and that drop functions are called correctly.
+     */
+    class tree_manipulator_t
+    {
+    public:
+        explicit tree_manipulator_t(tree_t& tree): m_tree(&tree)
+        {
+        }
+
+    private:
+        tree_t* m_tree;
+    };
+
     class tree_t
     {
+        friend struct temporary_tree_storage_t;
+        friend class single_operation_tree_manipulator_t;
+        friend class multi_operation_tree_manipulator_t;
+        friend class tree_manipulator_t;
     public:
         struct subtree_point_t
         {
@@ -209,51 +269,6 @@ namespace blt::gp
             ptrdiff_t start;
             // one past the end
             ptrdiff_t end;
-
-
-        };
-
-        struct byte_only_transaction_t
-        {
-            byte_only_transaction_t(tree_t& tree, const size_t bytes): tree(tree), data(nullptr), bytes(bytes)
-            {
-                move(bytes);
-            }
-
-            explicit byte_only_transaction_t(tree_t& tree): tree(tree), data(nullptr), bytes(0)
-            {
-            }
-
-            byte_only_transaction_t(const byte_only_transaction_t& copy) = delete;
-            byte_only_transaction_t& operator=(const byte_only_transaction_t& copy) = delete;
-
-            byte_only_transaction_t(byte_only_transaction_t&& move) noexcept: tree(move.tree), data(std::exchange(move.data, nullptr)),
-                                                                              bytes(std::exchange(move.bytes, 0))
-            {
-            }
-
-            byte_only_transaction_t& operator=(byte_only_transaction_t&& move) noexcept = delete;
-
-            void move(size_t bytes_to_move);
-
-            [[nodiscard]] bool empty() const
-            {
-                return bytes == 0;
-            }
-
-            ~byte_only_transaction_t()
-            {
-                if (!empty())
-                {
-                    tree.values.copy_from(data, bytes);
-                    bytes = 0;
-                }
-            }
-
-        private:
-            tree_t& tree;
-            u8* data;
-            size_t bytes;
         };
 
         explicit tree_t(gp_program& program): m_program(&program)
@@ -278,62 +293,9 @@ namespace blt::gp
          * This function copies the data from the provided tree, will attempt to reserve and copy in one step.
          * will avoid reallocation if enough space is already present.
          *
-         * This function is meant to copy into and replaces data inside the tree.
+         * This function is meant to copy into and replace data inside the tree.
          */
-        void copy_fast(const tree_t& copy)
-        {
-            if (this == &copy)
-                return;
-
-            operations.reserve(copy.operations.size());
-
-            auto copy_it = copy.operations.begin();
-            auto op_it = operations.begin();
-
-            size_t total_op_bytes = 0;
-            size_t total_copy_bytes = 0;
-
-            for (; op_it != operations.end(); ++op_it)
-            {
-                if (copy_it == copy.operations.end())
-                    break;
-                if (copy_it->is_value())
-                {
-                    copy.handle_refcount_increment(copy_it, total_copy_bytes);
-                    total_copy_bytes += copy_it->type_size();
-                }
-                if (op_it->is_value())
-                {
-                    handle_refcount_decrement(op_it, total_op_bytes);
-                    total_op_bytes += op_it->type_size();
-                }
-                *op_it = *copy_it;
-                ++copy_it;
-            }
-            const auto op_it_cpy = op_it;
-            for (; op_it != operations.end(); ++op_it)
-            {
-                if (op_it->is_value())
-                {
-                    handle_refcount_decrement(op_it, total_op_bytes);
-                    total_op_bytes += op_it->type_size();
-                }
-            }
-            operations.erase(op_it_cpy, operations.end());
-            for (; copy_it != copy.operations.end(); ++copy_it)
-            {
-                if (copy_it->is_value())
-                {
-                    copy.handle_refcount_increment(copy_it, total_copy_bytes);
-                    total_copy_bytes += copy_it->type_size();
-                }
-                operations.emplace_back(*copy_it);
-            }
-
-            values.reserve(copy.values.stored());
-            values.reset();
-            values.insert(copy.values);
-        }
+        void copy_fast(const tree_t& copy);
 
         tree_t(tree_t&& move) = default;
 
diff --git a/src/program.cpp b/src/program.cpp
index 747e792..c3bcf88 100644
--- a/src/program.cpp
+++ b/src/program.cpp
@@ -31,8 +31,8 @@ namespace blt::gp
     // this is largely to not break the tests :3
     // it's also to allow for quick setup of a gp program if you don't care how crossover or mutation is handled
     static advanced_mutation_t s_mutator;
-    // static subtree_crossover_t s_crossover;
-    static one_point_crossover_t s_crossover;
+    static subtree_crossover_t s_crossover;
+    // static one_point_crossover_t s_crossover;
     static ramped_half_initializer_t s_init;
 
     prog_config_t::prog_config_t(): mutator(s_mutator), crossover(s_crossover), pop_initializer(s_init)
diff --git a/src/tree.cpp b/src/tree.cpp
index fd45888..e730534 100644
--- a/src/tree.cpp
+++ b/src/tree.cpp
@@ -267,7 +267,7 @@ namespace blt::gp
         const auto point_begin_itr = operations.begin() + point.pos;
         const auto point_end_itr = operations.begin() + extent;
 
-        const size_t after_bytes = accumulate_type_sizes(point_end_itr, operations.end());
+        const size_t after_bytes = calculate_ephemeral_size(point_end_itr, operations.end());
 
         const size_t ops = std::distance(point_begin_itr, point_end_itr);
         operators.reserve(operators.size() + ops);
@@ -342,8 +342,8 @@ namespace blt::gp
             c2_subtree_operators.push_back(it);
         }
 
-        const size_t c1_stack_after_bytes = accumulate_type_sizes(c1_subtree_end_itr, operations.end());
-        const size_t c2_stack_after_bytes = accumulate_type_sizes(c2_subtree_end_itr, other_tree.operations.end());
+        const size_t c1_stack_after_bytes = calculate_ephemeral_size(c1_subtree_end_itr, operations.end());
+        const size_t c2_stack_after_bytes = calculate_ephemeral_size(c2_subtree_end_itr, other_tree.operations.end());
         const auto c1_total = static_cast<ptrdiff_t>(c1_stack_after_bytes + c1_subtree_bytes);
         const auto c2_total = static_cast<ptrdiff_t>(c2_stack_after_bytes + c2_subtree_bytes);
         const auto copy_ptr_c1 = get_thread_pointer_for_size<struct c1_t>(c1_total);
@@ -387,7 +387,7 @@ namespace blt::gp
         const auto point_begin_itr = operations.begin() + point.pos;
         const auto point_end_itr = operations.begin() + extent;
 
-        const size_t after_bytes = accumulate_type_sizes(point_end_itr, operations.end());
+        const size_t after_bytes = calculate_ephemeral_size(point_end_itr, operations.end());
 
         size_t for_bytes = 0;
         for (auto& it : iterate(point_begin_itr, point_end_itr).rev())
@@ -434,7 +434,7 @@ namespace blt::gp
         const auto point_begin_itr = operations.begin() + point.pos;
         const auto point_end_itr = operations.begin() + extent;
 
-        const size_t after_bytes = accumulate_type_sizes(point_end_itr, operations.end());
+        const size_t after_bytes = calculate_ephemeral_size(point_end_itr, operations.end());
 
         size_t for_bytes = 0;
         for (auto& it : iterate(point_begin_itr, point_end_itr).rev())
@@ -461,7 +461,7 @@ namespace blt::gp
 
     ptrdiff_t tree_t::insert_subtree(const subtree_point_t point, tree_t& other_tree)
     {
-        const size_t after_bytes = accumulate_type_sizes(operations.begin() + point.pos, operations.end());
+        const size_t after_bytes = calculate_ephemeral_size(operations.begin() + point.pos, operations.end());
         byte_only_transaction_t transaction{*this, after_bytes};
 
         auto insert = operations.begin() + point.pos;
@@ -635,6 +635,65 @@ namespace blt::gp
         }
     }
 
+    temporary_tree_storage_t::temporary_tree_storage_t(tree_t& tree): operations(&tree.operations), values(&tree.values)
+    {
+    }
+
+    void tree_t::copy_fast(const tree_t& copy)
+    {
+        if (this == &copy)
+            return;
+
+        operations.reserve(copy.operations.size());
+
+        auto copy_it = copy.operations.begin();
+        auto op_it = operations.begin();
+
+        size_t total_op_bytes = 0;
+        size_t total_copy_bytes = 0;
+
+        for (; op_it != operations.end(); ++op_it)
+        {
+            if (copy_it == copy.operations.end())
+                break;
+            if (copy_it->is_value())
+            {
+                copy.handle_refcount_increment(copy_it, total_copy_bytes);
+                total_copy_bytes += copy_it->type_size();
+            }
+            if (op_it->is_value())
+            {
+                handle_refcount_decrement(op_it, total_op_bytes);
+                total_op_bytes += op_it->type_size();
+            }
+            *op_it = *copy_it;
+            ++copy_it;
+        }
+        const auto op_it_cpy = op_it;
+        for (; op_it != operations.end(); ++op_it)
+        {
+            if (op_it->is_value())
+            {
+                handle_refcount_decrement(op_it, total_op_bytes);
+                total_op_bytes += op_it->type_size();
+            }
+        }
+        operations.erase(op_it_cpy, operations.end());
+        for (; copy_it != copy.operations.end(); ++copy_it)
+        {
+            if (copy_it->is_value())
+            {
+                copy.handle_refcount_increment(copy_it, total_copy_bytes);
+                total_copy_bytes += copy_it->type_size();
+            }
+            operations.emplace_back(*copy_it);
+        }
+
+        values.reserve(copy.values.stored());
+        values.reset();
+        values.insert(copy.values);
+    }
+
     void tree_t::clear(gp_program& program)
     {
         auto* f = &program;
@@ -766,7 +825,7 @@ namespace blt::gp
         byte_only_transaction_t move_data{*this};
         if (operations[point].is_value())
         {
-            const size_t after_bytes = accumulate_type_sizes(operations.begin() + static_cast<ptrdiff_t>(point) + 1, operations.end());
+            const size_t after_bytes = calculate_ephemeral_size(operations.begin() + static_cast<ptrdiff_t>(point) + 1, operations.end());
             move_data.move(after_bytes);
             if (operations[point].get_flags().is_ephemeral() && operations[point].has_ephemeral_drop())
             {
@@ -787,7 +846,7 @@ namespace blt::gp
         {
             if (move_data.empty())
             {
-                const size_t after_bytes = accumulate_type_sizes(operations.begin() + static_cast<ptrdiff_t>(point) + 1, operations.end());
+                const size_t after_bytes = calculate_ephemeral_size(operations.begin() + static_cast<ptrdiff_t>(point) + 1, operations.end());
                 move_data.move(after_bytes);
             }
             handle_operator_inserted(operations[point]);