Minor improvement in VmaBlockVector::Allocate. TestPool_SameSize: Added test for it.

src/Tests.cpp

@@ -1585,6 +1585,23 @@ static void TestPool_SameSize()
 
     items.clear();
 
+    ////////////////////////////////////////////////////////////////////////////////
+    // Test for allocation too large for pool
+
+    {
+        VmaAllocationCreateInfo allocCreateInfo = {};
+        allocCreateInfo.pool = pool;
+
+        VkMemoryRequirements memReq;
+        memReq.memoryTypeBits = UINT32_MAX;
+        memReq.alignment = 1;
+        memReq.size = poolCreateInfo.blockSize + 4;
+        
+        VmaAllocation alloc = nullptr;
+        res = vmaAllocateMemory(g_hAllocator, &memReq, &allocCreateInfo, &alloc, nullptr);
+        assert(res == VK_ERROR_OUT_OF_DEVICE_MEMORY && alloc == nullptr);
+    }
+
     vmaDestroyPool(g_hAllocator, pool);
 }
 

src/vk_mem_alloc.h

@@ -6694,6 +6694,12 @@ VkResult VmaBlockVector::Allocate(
     VmaSuballocationType suballocType,
     VmaAllocation* pAllocation)
 {
+    // Early reject: requested allocation size is larger that maximum block size for this block vector.
+    if(size > m_PreferredBlockSize)
+    {
+        return VK_ERROR_OUT_OF_DEVICE_MEMORY;
+    }
+
     const bool mapped = (createInfo.flags & VMA_ALLOCATION_CREATE_MAPPED_BIT) != 0;
     const bool isUserDataString = (createInfo.flags & VMA_ALLOCATION_CREATE_USER_DATA_COPY_STRING_BIT) != 0;