Added flag VMA_ALLOCATION_CREATE_CAN_ALIAS_BIT

include/vk_mem_alloc.h

@@ -961,6 +961,12 @@ typedef enum VmaAllocationCreateFlagBits {
     memory budget. Otherwise return `VK_ERROR_OUT_OF_DEVICE_MEMORY`.
     */
     VMA_ALLOCATION_CREATE_WITHIN_BUDGET_BIT = 0x00000100,
+    /** \brief Set this flag if the allocated memory will have aliasing resources.
+    * 
+    Usage of this flag prevents supplying `VkMemoryDedicatedAllocateInfoKHR` when VMA_ALLOCATION_CREATE_DEDICATED_MEMORY_BIT is specified.
+    Otherwise created dedicated memory will not be suitable for aliasing resources, resulting in Vulkan Validation Layer errors.
+    */
+    VMA_ALLOCATION_CREATE_CAN_ALIAS_BIT = 0x00000200,
 
     /** Allocation strategy that chooses smallest possible free range for the
     allocation.
@@ -6877,6 +6883,7 @@ private:
         bool withinBudget,
         bool map,
         bool isUserDataString,
+        bool canAliasMemory,
         void* pUserData,
         float priority,
         VkBuffer dedicatedBuffer,
@@ -15152,6 +15159,7 @@ VkResult VmaAllocator_T::AllocateMemoryOfType(
                 (finalCreateInfo.flags & VMA_ALLOCATION_CREATE_WITHIN_BUDGET_BIT) != 0,
                 (finalCreateInfo.flags & VMA_ALLOCATION_CREATE_MAPPED_BIT) != 0,
                 (finalCreateInfo.flags & VMA_ALLOCATION_CREATE_USER_DATA_COPY_STRING_BIT) != 0,
+                (finalCreateInfo.flags & VMA_ALLOCATION_CREATE_CAN_ALIAS_BIT) != 0,
                 finalCreateInfo.pUserData,
                 finalCreateInfo.priority,
                 dedicatedBuffer,
@@ -15197,6 +15205,7 @@ VkResult VmaAllocator_T::AllocateMemoryOfType(
             (finalCreateInfo.flags & VMA_ALLOCATION_CREATE_WITHIN_BUDGET_BIT) != 0,
             (finalCreateInfo.flags & VMA_ALLOCATION_CREATE_MAPPED_BIT) != 0,
             (finalCreateInfo.flags & VMA_ALLOCATION_CREATE_USER_DATA_COPY_STRING_BIT) != 0,
+            (finalCreateInfo.flags & VMA_ALLOCATION_CREATE_CAN_ALIAS_BIT) != 0,
             finalCreateInfo.pUserData,
             finalCreateInfo.priority,
             dedicatedBuffer,
@@ -15226,6 +15235,7 @@ VkResult VmaAllocator_T::AllocateDedicatedMemory(
     bool withinBudget,
     bool map,
     bool isUserDataString,
+    bool canAliasMemory,
     void* pUserData,
     float priority,
     VkBuffer dedicatedBuffer,
@@ -15252,6 +15262,8 @@ VkResult VmaAllocator_T::AllocateDedicatedMemory(
     allocInfo.allocationSize = size;
 
 #if VMA_DEDICATED_ALLOCATION || VMA_VULKAN_VERSION >= 1001000
+    if(!canAliasMemory)
+    {
         VkMemoryDedicatedAllocateInfoKHR dedicatedAllocInfo = { VK_STRUCTURE_TYPE_MEMORY_DEDICATED_ALLOCATE_INFO_KHR };
         if(m_UseKhrDedicatedAllocation || m_VulkanApiVersion >= VK_MAKE_VERSION(1, 1, 0))
         {
@@ -15267,6 +15279,7 @@ VkResult VmaAllocator_T::AllocateDedicatedMemory(
                 VmaPnextChainPushFront(&allocInfo, &dedicatedAllocInfo);
             }
         }
+    }
 #endif // #if VMA_DEDICATED_ALLOCATION || VMA_VULKAN_VERSION >= 1001000
 
 #if VMA_BUFFER_DEVICE_ADDRESS

src/Tests.cpp

@@ -5627,6 +5627,77 @@ static void TestAliasing()
     vkDestroyImage(g_hDevice, img1, g_Allocs);
 }
 
+static void TestAllocationAliasing()
+{
+    wprintf(L"Testing allocation aliasing...\n");
+    
+    /*
+    * Test whether using VMA_ALLOCATION_CREATE_CAN_ALIAS_BIT suppress validation layer error
+    * by don't supplying VkMemoryDedicatedAllocateInfoKHR to creation of dedicated memory
+    * that will be used to alias with some other textures.
+    */
+
+    VkImageCreateInfo imageInfo = { VK_STRUCTURE_TYPE_IMAGE_CREATE_INFO };
+    imageInfo.imageType = VK_IMAGE_TYPE_2D;
+    imageInfo.format = VK_FORMAT_R8G8B8A8_UNORM;
+    imageInfo.extent.depth = 1;
+    imageInfo.mipLevels = 1;
+    imageInfo.arrayLayers = 1;
+    imageInfo.samples = VK_SAMPLE_COUNT_1_BIT;
+    imageInfo.tiling = VK_IMAGE_TILING_OPTIMAL;
+    imageInfo.initialLayout = VK_IMAGE_LAYOUT_PREINITIALIZED;
+    imageInfo.usage = VK_IMAGE_USAGE_SAMPLED_BIT;
+
+    VmaAllocationCreateInfo allocationCreateInfo = {};
+    allocationCreateInfo.flags = VMA_ALLOCATION_CREATE_DEDICATED_MEMORY_BIT;
+    allocationCreateInfo.usage = VMA_MEMORY_USAGE_GPU_ONLY;
+
+    // Bind 2 textures together into same memory without VMA_ALLOCATION_CREATE_CAN_ALIAS_BIT and then with flag set
+    /*
+    {
+        VkImage originalImage;
+        VmaAllocation allocation;
+        imageInfo.extent.width = 640;
+        imageInfo.extent.height = 480;
+        VkResult res = vmaCreateImage(g_hAllocator, &imageInfo, &allocationCreateInfo, &originalImage, &allocation, nullptr);
+        TEST(res == VK_SUCCESS);
+
+        VkImage aliasingImage;
+        imageInfo.extent.width = 480;
+        imageInfo.extent.height = 256;
+        res = vkCreateImage(g_hDevice, &imageInfo, nullptr, &aliasingImage);
+        TEST(res == VK_SUCCESS);
+        // After binding there should be inevitable validation layer error VUID-vkBindImageMemory-memory-01509
+        res = vmaBindImageMemory(g_hAllocator, allocation, aliasingImage);
+        TEST(res == VK_SUCCESS);
+
+        vkDestroyImage(g_hDevice, aliasingImage, nullptr);
+        vmaDestroyImage(g_hAllocator, originalImage, allocation);
+    }
+    */
+    allocationCreateInfo.flags |= VMA_ALLOCATION_CREATE_CAN_ALIAS_BIT;
+    {
+        VkImage originalImage;
+        VmaAllocation allocation;
+        imageInfo.extent.width = 640;
+        imageInfo.extent.height = 480;
+        VkResult res = vmaCreateImage(g_hAllocator, &imageInfo, &allocationCreateInfo, &originalImage, &allocation, nullptr);
+        TEST(res == VK_SUCCESS);
+
+        VkImage aliasingImage;
+        imageInfo.extent.width = 480;
+        imageInfo.extent.height = 256;
+        res = vkCreateImage(g_hDevice, &imageInfo, nullptr, &aliasingImage);
+        TEST(res == VK_SUCCESS);
+        // Now with VMA_ALLOCATION_CREATE_CAN_ALIAS_BIT flag validation error is no more
+        res = vmaBindImageMemory(g_hAllocator, allocation, aliasingImage);
+        TEST(res == VK_SUCCESS);
+
+        vkDestroyImage(g_hDevice, aliasingImage, nullptr);
+        vmaDestroyImage(g_hAllocator, originalImage, allocation);
+    }
+}
+
 static void TestMapping()
 {
     wprintf(L"Testing mapping...\n");
@@ -6885,6 +6956,7 @@ void Test()
     TestDeviceCoherentMemory();
     TestBudget();
     TestAliasing();
+    TestAllocationAliasing();
     TestMapping();
     TestDeviceLocalMapped();
     TestMappingMultithreaded();
@@ -6908,12 +6980,15 @@ void Test()
         fclose(file);
     }
 
+    if(ConfigType >= CONFIG_TYPE_AVERAGE)
+    {
         TestDefragmentationSimple();
         TestDefragmentationFull();
         TestDefragmentationWholePool();
         TestDefragmentationGpu();
         TestDefragmentationIncrementalBasic();
         TestDefragmentationIncrementalComplex();
+    }
 
     // # Detailed tests
     FILE* file;