[dxvk] Initialize dummy resources to zero

Read access to unbound images and buffers usually yields
a result vector that contains zeroes in all components.

src/dxvk/dxvk_adapter.cpp

@@ -196,7 +196,12 @@ namespace dxvk {
     
     if (m_vki->vkCreateDevice(m_handle, &info, nullptr, &device) != VK_SUCCESS)
       throw DxvkError("DxvkAdapter: Failed to create device");
-    return new DxvkDevice(this, new vk::DeviceFn(m_vki->instance(), device), extensions, enabledFeatures);
+    
+    Rc<DxvkDevice> result = new DxvkDevice(this,
+      new vk::DeviceFn(m_vki->instance(), device),
+      extensions, enabledFeatures);
+    result->initResources();
+    return result;
   }
   
   

src/dxvk/dxvk_cmdlist.h

@@ -304,6 +304,17 @@ namespace dxvk {
       m_vkd->vkCmdEndRenderPass(m_buffer);
     }
     
+    
+    void cmdFillBuffer(
+            VkBuffer                dstBuffer,
+            VkDeviceSize            dstOffset,
+            VkDeviceSize            size,
+            uint32_t                data) {
+      m_vkd->vkCmdFillBuffer(m_buffer,
+        dstBuffer, dstOffset, size, data);
+    }
+    
+    
     void cmdPipelineBarrier(
             VkPipelineStageFlags    srcStageMask,
             VkPipelineStageFlags    dstStageMask,

src/dxvk/dxvk_context.cpp

@@ -175,6 +175,32 @@ namespace dxvk {
   }
   
   
+  void DxvkContext::clearBuffer(
+    const Rc<DxvkBuffer>&       buffer,
+          VkDeviceSize          offset,
+          VkDeviceSize          length,
+          uint32_t              value) {
+    this->renderPassEnd();
+    
+    auto slice = buffer->subSlice(offset, length);
+    
+    m_cmd->cmdFillBuffer(
+      slice.handle(),
+      slice.offset(),
+      slice.length(),
+      value);
+    
+    m_barriers.accessBuffer(slice,
+      VK_PIPELINE_STAGE_TRANSFER_BIT,
+      VK_ACCESS_TRANSFER_WRITE_BIT,
+      buffer->info().stages,
+      buffer->info().access);
+    m_barriers.recordCommands(m_cmd);
+    
+    m_cmd->trackResource(slice.resource());
+  }
+  
+  
   void DxvkContext::clearColorImage(
     const Rc<DxvkImage>&            image,
     const VkClearColorValue&        value,

src/dxvk/dxvk_context.h

@@ -135,6 +135,23 @@ namespace dxvk {
       const DxvkBufferSlice&      buffer,
             uint32_t              stride);
     
+    /**
+     * \brief Clears a buffer with a fixed value
+     * 
+     * Note that both \c offset and \c length must
+     * be multiples of four, and that \c value is
+     * consumed as a four-byte word.
+     * \param [in] buffer The buffer to clear
+     * \param [in] offset Offset of the range to clear
+     * \param [in] length Bumber of bytes to clear
+     * \param [in] value Clear value
+     */
+    void clearBuffer(
+      const Rc<DxvkBuffer>&       buffer,
+            VkDeviceSize          offset,
+            VkDeviceSize          length,
+            uint32_t              value);
+    
     /**
      * \brief Clears subresources of a color image
      * 

src/dxvk/dxvk_device.cpp

@@ -192,6 +192,11 @@ namespace dxvk {
   }
   
   
+  void DxvkDevice::initResources() {
+    m_unboundResources.clearResources(this);
+  }
+  
+  
   VkResult DxvkDevice::presentSwapImage(
     const VkPresentInfoKHR&         presentInfo) {
     m_statCounters.increment(DxvkStat::DevQueuePresents, 1);

src/dxvk/dxvk_device.h

@@ -35,6 +35,7 @@ namespace dxvk {
    * contexts. Multiple contexts can be created for a device.
    */
   class DxvkDevice : public RcObject {
+    friend class DxvkContext;
     friend class DxvkSubmissionQueue;
     
     constexpr static VkDeviceSize DefaultStagingBufferSize = 4 * 1024 * 1024;
@@ -276,46 +277,13 @@ namespace dxvk {
       const DxvkSwapchainProperties&  properties);
     
     /**
-     * \brief Dummy buffer handle
+     * \brief Initializes dummy resources
-     * \returns Use for unbound vertex buffers.
-     */
-    VkBuffer dummyBufferHandle() const {
-      return m_unboundResources.bufferHandle();
-    }
-    
-    /**
-     * \brief Dummy buffer descriptor
-     * \returns Descriptor that points to a dummy buffer
-     */
-    VkDescriptorBufferInfo dummyBufferDescriptor() const {
-      return m_unboundResources.bufferDescriptor();
-    }
-    
-    /**
-     * \brief Dummy buffer view descriptor
-     * \returns Dummy buffer view handle
-     */
-    VkBufferView dummyBufferViewDescriptor() const {
-      return m_unboundResources.bufferViewDescriptor();
-    }
-    
-    /**
-     * \brief Dummy sampler descriptor
-     * \returns Descriptor that points to a dummy sampler
-     */
-    VkDescriptorImageInfo dummySamplerDescriptor() const {
-      return m_unboundResources.samplerDescriptor();
-    }
-    
-    /**
-     * \brief Dummy image view descriptor
      * 
-     * \param [in] type Required view type
+     * Should be called after creating the device in
-     * \returns Descriptor that points to a dummy image
+     * case the device initialization was successful
+     * and the device is usable.
      */
-    VkDescriptorImageInfo dummyImageViewDescriptor(VkImageViewType type) const {
+    void initResources();
-      return m_unboundResources.imageViewDescriptor(type);
-    }
     
     /**
      * \brief Presents a swap chain image
@@ -379,7 +347,6 @@ namespace dxvk {
     VkQueue m_graphicsQueue = VK_NULL_HANDLE;
     VkQueue m_presentQueue  = VK_NULL_HANDLE;
     
-    // TODO fine-tune buffer sizes
     DxvkRecycler<DxvkCommandList,  16> m_recycledCommandLists;
     DxvkRecycler<DxvkStagingBuffer, 4> m_recycledStagingBuffers;
     
@@ -390,6 +357,48 @@ namespace dxvk {
     void recycleCommandList(
       const Rc<DxvkCommandList>& cmdList);
     
+    /**
+     * \brief Dummy buffer handle
+     * \returns Use for unbound vertex buffers.
+     */
+    VkBuffer dummyBufferHandle() const {
+      return m_unboundResources.bufferHandle();
+    }
+    
+    /**
+     * \brief Dummy buffer descriptor
+     * \returns Descriptor that points to a dummy buffer
+     */
+    VkDescriptorBufferInfo dummyBufferDescriptor() const {
+      return m_unboundResources.bufferDescriptor();
+    }
+    
+    /**
+     * \brief Dummy buffer view descriptor
+     * \returns Dummy buffer view handle
+     */
+    VkBufferView dummyBufferViewDescriptor() const {
+      return m_unboundResources.bufferViewDescriptor();
+    }
+    
+    /**
+     * \brief Dummy sampler descriptor
+     * \returns Descriptor that points to a dummy sampler
+     */
+    VkDescriptorImageInfo dummySamplerDescriptor() const {
+      return m_unboundResources.samplerDescriptor();
+    }
+    
+    /**
+     * \brief Dummy image view descriptor
+     * 
+     * \param [in] type Required view type
+     * \returns Descriptor that points to a dummy image
+     */
+    VkDescriptorImageInfo dummyImageViewDescriptor(VkImageViewType type) const {
+      return m_unboundResources.imageViewDescriptor(type);
+    }
+    
   };
   
 }

src/dxvk/dxvk_unbound.cpp

@@ -25,6 +25,21 @@ namespace dxvk {
   }
   
   
+  void DxvkUnboundResources::clearResources(DxvkDevice* dev) {
+    const Rc<DxvkContext> ctx = dev->createContext();
+    ctx->beginRecording(dev->createCommandList());
+    
+    this->clearBuffer(ctx, m_buffer);
+    this->clearImage(ctx, m_image1D);
+    this->clearImage(ctx, m_image2D);
+    this->clearImage(ctx, m_image3D);
+    
+    dev->submitCommandList(
+      ctx->endRecording(),
+      nullptr, nullptr);
+  }
+  
+  
   Rc<DxvkSampler> DxvkUnboundResources::createSampler(DxvkDevice* dev) {
     DxvkSamplerCreateInfo info;
     info.minFilter      = VK_FILTER_LINEAR;
@@ -50,11 +65,13 @@ namespace dxvk {
   Rc<DxvkBuffer> DxvkUnboundResources::createBuffer(DxvkDevice* dev) {
     DxvkBufferCreateInfo info;
     info.size       = 4;
-    info.usage      = VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT
+    info.usage      = VK_BUFFER_USAGE_TRANSFER_DST_BIT
+                    | VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT
                     | VK_BUFFER_USAGE_STORAGE_BUFFER_BIT
                     | VK_BUFFER_USAGE_UNIFORM_TEXEL_BUFFER_BIT
                     | VK_BUFFER_USAGE_STORAGE_TEXEL_BUFFER_BIT;
-    info.stages     = VK_PIPELINE_STAGE_VERTEX_SHADER_BIT
+    info.stages     = VK_PIPELINE_STAGE_TRANSFER_BIT
+                    | VK_PIPELINE_STAGE_VERTEX_SHADER_BIT
                     | VK_PIPELINE_STAGE_TESSELLATION_CONTROL_SHADER_BIT
                     | VK_PIPELINE_STAGE_TESSELLATION_EVALUATION_SHADER_BIT
                     | VK_PIPELINE_STAGE_GEOMETRY_SHADER_BIT
@@ -93,9 +110,11 @@ namespace dxvk {
     info.extent      = { 1, 1, 1 };
     info.numLayers   = layers;
     info.mipLevels   = 1;
-    info.usage       = VK_IMAGE_USAGE_SAMPLED_BIT
+    info.usage       = VK_IMAGE_USAGE_TRANSFER_DST_BIT
+                     | VK_IMAGE_USAGE_SAMPLED_BIT
                      | VK_IMAGE_USAGE_STORAGE_BIT;
-    info.stages      = VK_PIPELINE_STAGE_VERTEX_SHADER_BIT
+    info.stages      = VK_PIPELINE_STAGE_TRANSFER_BIT
+                     | VK_PIPELINE_STAGE_VERTEX_SHADER_BIT
                      | VK_PIPELINE_STAGE_TESSELLATION_CONTROL_SHADER_BIT
                      | VK_PIPELINE_STAGE_TESSELLATION_EVALUATION_SHADER_BIT
                      | VK_PIPELINE_STAGE_GEOMETRY_SHADER_BIT
@@ -147,4 +166,23 @@ namespace dxvk {
     }
   }
   
+  
+  void DxvkUnboundResources::clearBuffer(
+    const Rc<DxvkContext>&  ctx,
+    const Rc<DxvkBuffer>&   buffer) {
+    ctx->clearBuffer(buffer, 0, buffer->info().size, 0);
+  }
+  
+  
+  void DxvkUnboundResources::clearImage(
+    const Rc<DxvkContext>&  ctx,
+    const Rc<DxvkImage>&    image) {
+    ctx->clearColorImage(image,
+      VkClearColorValue { },
+      VkImageSubresourceRange {
+        VK_IMAGE_ASPECT_COLOR_BIT,
+        0, image->info().mipLevels,
+        0, image->info().numLayers });
+  }
+  
 }

src/dxvk/dxvk_unbound.h

@@ -35,8 +35,9 @@ namespace dxvk {
     /**
      * \brief Dummy buffer descriptor
      * 
-     * Points to a small buffer with undefined
+     * Points to a small buffer filled with zeroes.
-     * values. Do not access this buffer.
+     * Do not write to this buffer, and do not use
+     * it if out-of-bounds read access is possible.
      * \returns Dummy buffer descriptor
      */
     VkDescriptorBufferInfo bufferDescriptor() const {
@@ -95,6 +96,14 @@ namespace dxvk {
       return result;
     }
     
+    /**
+     * \brief Clears the resources
+     * 
+     * Initializes all images and buffers to zero.
+     * \param [in] dev The DXVK device handle
+     */
+    void clearResources(DxvkDevice* dev);
+    
   private:
     
     Rc<DxvkSampler> m_sampler;
@@ -136,6 +145,14 @@ namespace dxvk {
     const DxvkImageView* getImageView(
             VkImageViewType type) const;
     
+    void clearBuffer(
+      const Rc<DxvkContext>&  ctx,
+      const Rc<DxvkBuffer>&   buffer);
+    
+    void clearImage(
+      const Rc<DxvkContext>&  ctx,
+      const Rc<DxvkImage>&    image);
+    
   };
   
 }