silly code doesn't work

CMakeLists.txt

@@ -1,5 +1,5 @@
 cmake_minimum_required(VERSION 3.25)
-project(blt-gp VERSION 0.0.8)
+project(blt-gp VERSION 0.0.9)
 
 option(ENABLE_ADDRSAN "Enable the address sanitizer" OFF)
 option(ENABLE_UBSAN "Enable the ub sanitizer" OFF)

include/blt/gp/program.h

@@ -16,10 +16,10 @@
  *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-#include <cstddef>
 #ifndef BLT_GP_PROGRAM_H
 #define BLT_GP_PROGRAM_H
 
+#include <cstddef>
 #include <blt/gp/fwdecl.h>
 #include <functional>
 #include <blt/std/ranges.h>
@@ -89,6 +89,99 @@ namespace blt::gp
     {
             constexpr static blt::size_t PAGE_SIZE = 0x1000;
         public:
+            /**
+             * Pushes an instance of an object on to the stack
+             * @tparam T type to push
+             * @param value universal reference to the object to push
+             */
+            template<typename T>
+            void push(T&& value)
+            {
+                auto ptr = allocate_bytes<T>();
+                head->metadata.offset = ptr + sizeof(T);
+                new(ptr) T(std::forward<T>(value));
+            }
+            
+            template<typename T>
+            T pop()
+            {
+                if (head == nullptr)
+                    throw std::runtime_error("Silly boi the stack is empty!");
+                if (head->remaining_bytes_in_block() - head->storage_size() < sizeof(T))
+                    throw std::runtime_error("Mismatched Types!");
+                T t = *reinterpret_cast<T*>(head->metadata.offset - sizeof(T));
+                head->metadata.offset -= sizeof(T);
+                if (head->used_bytes_in_block() == static_cast<blt::ptrdiff_t>(head->storage_size()))
+                {
+                    auto ptr = head;
+                    head = head->metadata.prev;
+                    delete ptr;
+                }
+                return t;
+            }
+            
+            template<typename T>
+            T& from(blt::size_t bytes)
+            {
+                auto remaining_bytes = static_cast<blt::i64>(bytes);
+                blt::i64 bytes_into_block = 0;
+                block* blk = head;
+                while (remaining_bytes > 0)
+                {
+                    if (blk == nullptr)
+                        throw std::runtime_error("Requested size is beyond the scope of this stack!");
+                    auto bytes_available = blk->used_bytes_in_block() - remaining_bytes;
+                    bytes_into_block = remaining_bytes;
+                    if (bytes_available < 0)
+                    {
+                        remaining_bytes = -bytes_available;
+                        blk = head->metadata.prev;
+                    } else
+                        break;
+                }
+                if (blk == nullptr)
+                    throw std::runtime_error("Some nonsense is going on. This function already smells");
+                return *reinterpret_cast<T*>((blk->metadata.offset - bytes_into_block) - sizeof(T));
+            }
+            
+            [[nodiscard]] bool empty() const
+            {
+                if (head == nullptr)
+                    return true;
+                if (head->metadata.prev != nullptr)
+                    return false;
+                return head->used_bytes_in_block() == static_cast<blt::ptrdiff_t>(head->storage_size());
+            }
+            
+            stack_allocator() = default;
+            
+            stack_allocator(const stack_allocator& copy) = delete;
+            
+            stack_allocator& operator=(const stack_allocator& copy) = delete;
+            
+            stack_allocator(stack_allocator&& move) noexcept
+            {
+                head = move.head;
+                move.head = nullptr;
+            }
+            
+            stack_allocator& operator=(stack_allocator&& move) noexcept
+            {
+                head = move.head;
+                move.head = nullptr;
+                return *this;
+            }
+            
+            ~stack_allocator()
+            {
+                block* current = head;
+                while (current != nullptr)
+                {
+                    block* ptr = current;
+                    current = current->metadata.prev;
+                    delete ptr;
+                }
+            }
         
         private:
             struct block
@@ -108,17 +201,62 @@ namespace blt::gp
                     metadata.offset = buffer;
                 }
                 
-                [[nodiscard]] blt::size_t remainder_after_meta() const
+                [[nodiscard]] blt::ptrdiff_t storage_size() const
                 {
-                    return metadata.size - sizeof(typename block::block_metadata_t);
+                    return static_cast<blt::ptrdiff_t>(metadata.size - sizeof(typename block::block_metadata_t));
                 }
                 
-                [[nodiscard]] blt::ptrdiff_t remaining_bytes() const
+                [[nodiscard]] blt::ptrdiff_t remaining_bytes_in_block() const
+                {
+                    return storage_size() - static_cast<blt::ptrdiff_t>(metadata.offset - buffer);
+                }
+                
+                [[nodiscard]] blt::ptrdiff_t used_bytes_in_block() const
                 {
                     return static_cast<blt::ptrdiff_t>(metadata.offset - buffer);
                 }
             };
             
+            template<typename T>
+            void* allocate_bytes()
+            {
+                auto ptr = get_aligned_pointer(sizeof(T), alignof(T));
+                if (ptr == nullptr)
+                    push_block_for<T>();
+                ptr = get_aligned_pointer(sizeof(T), alignof(T));
+                if (ptr == nullptr)
+                    throw std::bad_alloc();
+                return ptr;
+            }
+            
+            void* get_aligned_pointer(blt::size_t bytes, blt::size_t alignment)
+            {
+                if (head == nullptr)
+                    return nullptr;
+                blt::size_t remaining_bytes = head->remaining_bytes_in_block();
+                auto* pointer = static_cast<void*>(head->metadata.offset);
+                return std::align(alignment, bytes, pointer, remaining_bytes);
+            }
+            
+            template<typename T>
+            void push_block_for()
+            {
+                push_block(std::max(PAGE_SIZE, to_nearest_page_size(sizeof(T))));
+            }
+            
+            void push_block(blt::size_t size)
+            {
+                auto blk = allocate_block(size);
+                if (head == nullptr)
+                {
+                    head = blk;
+                    return;
+                }
+                head->metadata.next = blk;
+                blk->metadata.prev = head;
+                head = blk;
+            }
+            
             static size_t to_nearest_page_size(blt::size_t bytes)
             {
                 constexpr static blt::size_t MASK = ~(PAGE_SIZE - 1);