Limit Vulkan memory allocation size to 1 GiB

src/Vulkan/VkConfig.h

@@ -88,4 +88,10 @@ constexpr int SUBPIXEL_PRECISION_MASK = 0xFFFFFFFF >> (32 - SUBPIXEL_PRECISION_B
 #define SWIFTSHADER_EXTERNAL_SEMAPHORE_OPAQUE_FD     1
 #endif
 
+constexpr VkDeviceSize MAX_MEMORY_ALLOCATION_SIZE = 0x40000000ull;  // 0x40000000 = 1 GiB
+
+// Memory offset calculations in 32-bit SIMD elements limit us to addressing at most 4 GiB.
+// Signed arithmetic further restricts it to 2 GiB.
+static_assert(MAX_MEMORY_ALLOCATION_SIZE <= 0x80000000ull, "maxMemoryAllocationSize must not exceed 2 GiB");
+
 #endif // VK_CONFIG_HPP_

src/Vulkan/VkDeviceMemory.cpp

@@ -100,7 +100,9 @@ public:
 	{
 		void *buffer = vk::allocate(size, REQUIRED_MEMORY_ALIGNMENT, DEVICE_MEMORY);
 		if(!buffer)
+		{
 			return VK_ERROR_OUT_OF_DEVICE_MEMORY;
+		}
 
 		*pBuffer = buffer;
 		return VK_SUCCESS;
@@ -173,6 +175,11 @@ size_t DeviceMemory::ComputeRequiredAllocationSize(const VkMemoryAllocateInfo *p
 
 VkResult DeviceMemory::allocate()
 {
+	if(size > MAX_MEMORY_ALLOCATION_SIZE)
+	{
+		return VK_ERROR_OUT_OF_DEVICE_MEMORY;
+	}
+
 	VkResult result = VK_SUCCESS;
 	if(!buffer)
 	{

src/Vulkan/VkPhysicalDevice.cpp

@@ -326,7 +326,7 @@ void PhysicalDevice::getProperties(VkPhysicalDeviceIDProperties *properties) con
 
 void PhysicalDevice::getProperties(VkPhysicalDeviceMaintenance3Properties *properties) const
 {
-	properties->maxMemoryAllocationSize = 1u << 31;
+	properties->maxMemoryAllocationSize = MAX_MEMORY_ALLOCATION_SIZE;
 	properties->maxPerSetDescriptors = 1024;
 }