layers: Add DrawCmd perf warning to Best Practices

Change-Id: I7b4530393df8ff7b93f2ceb484ff49a1fb6e92c8
KhronosGroup · Nov 8, 2019 · f4206ce · f4206ce
1 parent 2a8bc25
commit f4206ce
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Showing 2 changed files with 24 additions and 0 deletions.
diff --git a/layers/best_practices.cpp b/layers/best_practices.cpp
@@ -810,3 +810,25 @@ void BestPractices::PostCallRecordQueueBindSparse(VkQueue queue, uint32_t bindIn
         }
     }
 }
+
+bool BestPractices::PreCallValidateCmdClearAttachments(VkCommandBuffer commandBuffer, uint32_t attachmentCount,
+                                        const VkClearAttachment* pAttachments, uint32_t rectCount, const VkClearRect* pRects) {
+    bool skip = false;
+    const CMD_BUFFER_STATE* cb_node = GetCBState(commandBuffer);
+    if (!cb_node) return skip;
+
+        // Warn if this is issued prior to Draw Cmd and clearing the entire attachment
+    if (!cb_node->hasDrawCmd && (cb_node->activeRenderPassBeginInfo.renderArea.extent.width == pRects[0].rect.extent.width) &&
+        (cb_node->activeRenderPassBeginInfo.renderArea.extent.height == pRects[0].rect.extent.height)) {
+        // There are times where app needs to use ClearAttachments (generally when reusing a buffer inside of a render pass)
+        // This warning should be made more specific. It'd be best to avoid triggering this test if it's a use that must call
+        // CmdClearAttachments.
+        skip |= log_msg(report_data, VK_DEBUG_REPORT_PERFORMANCE_WARNING_BIT_EXT, VK_DEBUG_REPORT_OBJECT_TYPE_COMMAND_BUFFER_EXT,
+                        HandleToUint64(commandBuffer), kVUID_Core_DrawState_ClearCmdBeforeDraw,
+                        "vkCmdClearAttachments() issued on %s prior to any Draw Cmds. It is recommended you "
+                        "use RenderPass LOAD_OP_CLEAR on Attachments prior to any Draw.",
+                        report_data->FormatHandle(commandBuffer).c_str());
+    }
+
+        return skip;
+}
diff --git a/layers/best_practices.h b/layers/best_practices.h
@@ -120,6 +120,8 @@ class BestPractices : public ValidationStateTracker {
                                         VkFence fence) const;
     void PostCallRecordQueueBindSparse(VkQueue queue, uint32_t bindInfoCount, const VkBindSparseInfo* pBindInfo, VkFence fence,
                                        VkResult result);
+    bool PreCallValidateCmdClearAttachments(VkCommandBuffer commandBuffer, uint32_t attachmentCount,
+                                            const VkClearAttachment* pAttachments, uint32_t rectCount, const VkClearRect* pRects);
 
   private:
     uint32_t instance_api_version;