From 8e009a1d6673431fa9a48e0d5d467a76cfdd6ab2 Mon Sep 17 00:00:00 2001
From: Lynix <lynix680@gmail.com>
Date: Thu, 15 Sep 2016 00:46:59 +0200
Subject: [PATCH] Core/MemoryHelper: Add portable stack allocation

Former-commit-id: 50b96029c53d1784f028148f1ec15ae2cf98d036 [formerly eb3398905190df3d0dc77c8a3b54bb455059e39b] [formerly bfac4638e043161208ee7cf4735a788b1427f73e [formerly 1ee0a59ab5aa407c995afd287a9aaa4307075754]]
Former-commit-id: 521c4248c638e5141534cd1d223d8f563693b821 [formerly 203f6191b3b24ccb2e04d330372973dadfb81e1d]
Former-commit-id: 140a5c705819055b4d27f43156b079d6142049a5
---
 include/Nazara/Core/MemoryHelper.hpp | 35 +++++++++++++++++++++
 include/Nazara/Core/MemoryHelper.inl | 46 ++++++++++++++++++++++++++++
 2 files changed, 81 insertions(+)

diff --git a/include/Nazara/Core/MemoryHelper.hpp b/include/Nazara/Core/MemoryHelper.hpp
index e2f295622..ff81ea083 100644
--- a/include/Nazara/Core/MemoryHelper.hpp
+++ b/include/Nazara/Core/MemoryHelper.hpp
@@ -7,6 +7,27 @@
 #ifndef NAZARA_MEMORYHELPER_HPP
 #define NAZARA_MEMORYHELPER_HPP
 
+#if defined(NAZARA_COMPILER_MSVC)
+
+#include <malloc.h>
+
+#define NAZARA_ALLOCA(size) _alloca(size)
+#define NAZARA_ALLOCA_SUPPORT
+
+#elif defined(NAZARA_COMPILER_CLANG) || defined(NAZARA_COMPILER_GCC) || defined(NAZARA_COMPILER_INTEL)
+#include <alloca.h>
+
+#define NAZARA_ALLOCA(size) alloca(size)
+#define NAZARA_ALLOCA_SUPPORT
+
+#endif
+
+#ifdef NAZARA_ALLOCA_SUPPORT
+	#define NazaraStackAllocation(size) Nz::StackAllocation(NAZARA_ALLOCA(size))
+#else
+	#define NazaraStackAllocation(size) Nz::StackAllocation(Nz::OperatorNew(size))
+#endif
+
 #include <cstddef>
 
 namespace Nz
@@ -16,6 +37,20 @@ namespace Nz
 
 	template<typename T, typename... Args>
 	T* PlacementNew(T* ptr, Args&&... args);
+
+	class StackAllocation
+	{
+		public:
+			explicit StackAllocation(void* stackMemory);
+			~StackAllocation();
+
+			void* GetPtr();
+
+			operator void*();
+
+		private:
+			void* m_ptr;
+	};
 }
 
 #include <Nazara/Core/MemoryHelper.inl>
diff --git a/include/Nazara/Core/MemoryHelper.inl b/include/Nazara/Core/MemoryHelper.inl
index 23a745a44..d3fe43155 100644
--- a/include/Nazara/Core/MemoryHelper.inl
+++ b/include/Nazara/Core/MemoryHelper.inl
@@ -9,6 +9,7 @@
 	#define NAZARA_DEBUG_NEWREDEFINITION_DISABLE_REDEFINITION
 #endif
 
+#include <Nazara/Core/MemoryHelper.hpp>
 #include <Nazara/Core/MemoryManager.hpp>
 #include <new>
 #include <utility>
@@ -62,6 +63,51 @@ namespace Nz
 	{
 		return new (ptr) T(std::forward<Args>(args)...);
 	}
+
+	/*!
+	* \ingroup core
+	* \class Nz::StackAllocation
+	* \brief Core class that represents a stack allocation
+	*/
+
+
+	/*!
+	* \brief Constructs a StackAllocation object with a pointer to a memory allocated with NAZARA_ALLOCA or OperatorNew is alloca is not supported
+	*
+	* \param ptr Pointer to raw memory
+	*/
+	inline StackAllocation::StackAllocation(void* stackMemory) :
+	m_ptr(stackMemory)
+	{
+	}
+
+	/*!
+	* \brief Destructs the object and release memory if necessary
+	*/
+	inline StackAllocation::~StackAllocation()
+	{
+		#ifndef NAZARA_ALLOCA_SUPPORT
+		OperatorDelete(m_ptr);
+		#endif
+	}
+
+	/*!
+	* \brief Access the internal pointer
+	* \return internal memory pointer
+	*/
+	inline void* StackAllocation::GetPtr()
+	{
+		return m_ptr;
+	}
+
+	/*!
+	* \brief Access the internal pointer
+	* \return internal memory pointer
+	*/
+	inline StackAllocation::operator void*()
+	{
+		return m_ptr;
+	}
 }
 
 #include <Nazara/Core/DebugOff.hpp>