[dxvk] Fix deferred clear logic for overlapping image views

If we clear the same image subresources twice with different views
and then start rendering to one view, we may end up clearing to
the wrong clear value.

src/dxvk/dxvk_context.cpp

@@ -1868,7 +1868,8 @@ namespace dxvk {
           entry.clearValue.depthStencil.stencil = clearValue.depthStencil.stencil;
         
         return;
-      }
+      } else if (entry.imageView->checkSubresourceOverlap(imageView))
+        this->flushClears(false);
     }
 
     m_deferredClears.push_back({ imageView, 0, clearAspects, clearValue });
@@ -1883,7 +1884,8 @@ namespace dxvk {
         entry.discardAspects |= discardAspects;
         entry.clearAspects &= ~discardAspects;
         return;
-      }
+      } else if (entry.imageView->checkSubresourceOverlap(imageView))
+        this->flushClears(false);
     }
 
     m_deferredClears.push_back({ imageView, discardAspects });

src/dxvk/dxvk_image.h

@@ -469,6 +469,23 @@ namespace dxvk {
       return result;
     }
 
+    /**
+     * \brief Checks whether this view overlaps with another one
+     *
+     * Two views overlap if they were created for the same
+     * image and have at least one subresource in common.
+     * \param [in] view The other view to check
+     * \returns \c true if the two views overlap
+     */
+    bool checkSubresourceOverlap(const Rc<DxvkImageView>& view) const {
+      if (likely(m_image != view->m_image))
+        return false;
+
+      return vk::checkSubresourceRangeOverlap(
+        this->imageSubresources(),
+        view->imageSubresources());
+    }
+
   private:
     
     Rc<vk::DeviceFn>  m_vkd;