Adding zenservice code

1 files changed, 165 insertions, 0 deletions

diff --git a/zencore/memory.cpp b/zencore/memory.cpp
new file mode 100644
index 000000000..63d61f5e1
--- /dev/null
+++ b/zencore/memory.cpp
@@ -0,0 +1,165 @@
+// Copyright Epic Games, Inc. All Rights Reserved.
+
+#include <malloc.h>
+#include <zencore/intmath.h>
+#include <zencore/memory.h>
+
+#include <doctest/doctest.h>
+
+namespace zen {
+
+//////////////////////////////////////////////////////////////////////////
+
+MemoryArena::MemoryArena()
+{
+}
+
+MemoryArena::~MemoryArena()
+{
+}
+
+void*
+MemoryArena::Alloc(size_t size, size_t alignment)
+{
+	return _mm_malloc(size, alignment);
+}
+
+void
+MemoryArena::Free(void* ptr)
+{
+	if (ptr)
+		_mm_free(ptr);
+}
+
+//////////////////////////////////////////////////////////////////////////
+
+void*
+Memory::Alloc(size_t size, size_t alignment)
+{
+	return _mm_malloc(size, alignment);
+}
+
+void
+Memory::Free(void* ptr)
+{
+	if (ptr)
+		_mm_free(ptr);
+}
+
+//////////////////////////////////////////////////////////////////////////
+
+ChunkingLinearAllocator::ChunkingLinearAllocator(uint64_t ChunkSize, uint64_t ChunkAlignment)
+: m_ChunkSize(ChunkSize)
+, m_ChunkAlignment(ChunkAlignment)
+{
+}
+
+ChunkingLinearAllocator::~ChunkingLinearAllocator()
+{
+	Reset();
+}
+
+void
+ChunkingLinearAllocator::Reset()
+{
+	for (void* ChunkEntry : m_ChunkList)
+	{
+		Memory::Free(ChunkEntry);
+	}
+	m_ChunkList.clear();
+
+	m_ChunkCursor	   = nullptr;
+	m_ChunkBytesRemain = 0;
+}
+
+void*
+ChunkingLinearAllocator::Alloc(size_t Size, size_t Alignment)
+{
+	ZEN_ASSERT_SLOW(zen::IsPow2(Alignment));
+
+	// This could be improved in a bunch of ways
+	//
+	// * We pessimistically allocate memory even though there may be enough memory available for a single allocation due to the way we take
+	//   alignment into account below
+	// * The block allocation size could be chosen to minimize slack for the case when multiple oversize allocations are made rather than
+	//   minimizing the number of chunks
+	// * ...
+
+	const uint64_t AllocationSize = zen::RoundUp(Size, Alignment);
+
+	if (m_ChunkBytesRemain < (AllocationSize + Alignment - 1))
+	{
+		const uint64_t ChunkSize = zen::RoundUp(zen::Max(m_ChunkSize, Size), m_ChunkSize);
+		void*		   ChunkPtr	 = Memory::Alloc(ChunkSize, m_ChunkAlignment);
+		m_ChunkCursor			 = reinterpret_cast<uint8_t*>(ChunkPtr);
+		m_ChunkBytesRemain		 = ChunkSize;
+		m_ChunkList.push_back(ChunkPtr);
+	}
+
+	const uint64_t AlignFixup = (Alignment - reinterpret_cast<uintptr_t>(m_ChunkCursor)) & (Alignment - 1);
+	void*		   ReturnPtr  = m_ChunkCursor + AlignFixup;
+	const uint64_t Delta	  = AlignFixup + AllocationSize;
+
+	ZEN_ASSERT_SLOW(m_ChunkBytesRemain >= Delta);
+
+	m_ChunkCursor += Delta;
+	m_ChunkBytesRemain -= Delta;
+
+	ZEN_ASSERT_SLOW(IsPointerAligned(ReturnPtr, Alignment));
+
+	return ReturnPtr;
+}
+
+//////////////////////////////////////////////////////////////////////////
+//
+// Unit tests
+//
+
+TEST_CASE("ChunkingLinearAllocator")
+{
+	ChunkingLinearAllocator Allocator(4096);
+
+	void* p1 = Allocator.Alloc(1, 1);
+	void* p2 = Allocator.Alloc(1, 1);
+
+	CHECK(p1 != p2);
+
+	void* p3 = Allocator.Alloc(1, 4);
+	CHECK(IsPointerAligned(p3, 4));
+
+	void* p3_2 = Allocator.Alloc(1, 4);
+	CHECK(IsPointerAligned(p3_2, 4));
+
+	void* p4 = Allocator.Alloc(1, 8);
+	CHECK(IsPointerAligned(p4, 8));
+
+	for (int i = 0; i < 100; ++i)
+	{
+		void* p0 = Allocator.Alloc(64);
+		ZEN_UNUSED(p0);
+	}
+}
+
+TEST_CASE("MemoryView")
+{
+	{
+		uint8_t	   Array1[16];
+		MemoryView View1 = MakeMemoryView(Array1);
+		CHECK(View1.GetSize() == 16);
+	}
+
+	{
+		uint32_t   Array2[16];
+		MemoryView View2 = MakeMemoryView(Array2);
+		CHECK(View2.GetSize() == 64);
+	}
+
+	CHECK(MakeMemoryView<float>({1.0f, 1.2f}).GetSize() == 8);
+}
+
+void
+memory_forcelink()
+{
+}
+
+}  // namespace zen