feat: move allocator and slots into codegen folder

include/codegen/allocator.hpp

@@ -0,0 +1,66 @@
+#pragma once
+#include "prelude/string.hpp"
+#include "codegen/slot.hpp"
+
+#define AVAILABLE_REGISTERS 4
+#define AVAILABLE_STACK_SIZE 4096
+
+template <typename Slot, typename SlotAddr = const StringView &>
+class Allocator
+{
+public:
+    virtual ~Allocator() {};
+
+public:
+    virtual const Slot &Allocate(SlotAddr addr) = 0;
+    virtual const Slot &Resolve(SlotAddr addr) = 0;
+};
+
+class SlotAllocator : public Allocator<IR::IRSlot>
+{
+public:
+    SlotAllocator() = default;
+    ~SlotAllocator() = default;
+
+public:
+    const IR::IRSlot &Allocate(const StringView &addr) override
+    {
+        if (m_regs < AVAILABLE_REGISTERS)
+        {
+            m_slots.Push(IR::IRSlot(addr, m_regs++, IR::IRSlot::Type::REGISTRY));
+            return m_slots.data[m_slots.size - 1];
+        }
+        if (m_offset_counter + 8 <= AVAILABLE_STACK_SIZE)
+        {
+            m_offset_counter += 8;
+            m_slots.Push(IR::IRSlot(addr, m_offset_counter, IR::IRSlot::Type::STACK));
+            return m_slots.data[m_slots.size - 1];
+        }
+        // TODO: proper error handling (stack overflow etc.)
+        assert(0 && "failed to allocate local");
+    }
+
+    const IR::IRSlot &Resolve(const StringView &addr) override
+    {
+        for (size_t i = 0; i < m_slots.size; ++i)
+        {
+            if (m_slots.data[i].GetAddr() == addr)
+            {
+                return m_slots.data[i];
+            }
+        }
+
+        assert(0 && "could not resolve stack offset for specified address");
+    }
+
+public:
+    View<IR::IRSlot> slots() const { return m_slots.view(); }
+
+public:
+    unsigned int GetStackSize() const { return m_offset_counter; }
+
+public:
+    int m_regs = 0;
+    unsigned int m_offset_counter = 0;
+    Builder<IR::IRSlot> m_slots;
+};