[Vk] Improve Stencil Handling and Fix Read-After-Write Hazard #235

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Shinmegumi merged 1 commit from wildcard/eden:fixRAWsyncerror into master

2025-08-23 20:04:48 +02:00

wildcard commented

2025-08-09 22:36:15 +02:00

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Improves stencil handling:
- Adds surface type detection to distinguish between color, depth, stencil, and depth-stencil formats
- Only enables stencil load/store operations for surfaces that actually contain stencil data
- Avoids unnecessary stencil operations for non-stencil formats (DONT_CARE)
Fixes read-after-write (RAW) synchronization hazards:
- Adds a subpass self-dependency (subpass 0 → subpass 0)
- Synchronizes color/depth writes with subsequent shader reads
- Uses VK_DEPENDENCY_BY_REGION_BIT for efficient synchronization
- Covers all possible relevant stages,
  • src: Color output + Early/Late fragment tests
  • dst: Fragment shader
  • Access: Write → Read transitions
  here is what hazard looks like [1147.550616] Render.Vulkan video_core/vulkan_common/vulkan_debug_callback.cpp:DebugUtilCallback:55: Validation Error: [ SYNC-HAZARD-READ-AFTER-WRITE ] Object 0: handle = 0x7409630000000192, type = VK_OBJECT_TYPE_IMAGE_VIEW; | MessageID = 0xe4d96472 | vkCmdDrawIndexed: Hazard READ_AFTER_WRITE for VkImageView 0x7409630000000192[], in VkCommandBuffer 0xb400007cb003ea70[], and VkPipeline 0x44d3470000000213[], VkDescriptorSet 0x0[], type: VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, imageLayout: VK_IMAGE_LAYOUT_GENERAL, binding #2, index 0. Access info (usage: SYNC_FRAGMENT_SHADER_SHADER_SAMPLED_READ, prior_usage: SYNC_IMAGE_LAYOUT_TRANSITION, write_barriers: SYNC_FRAGMENT_SHADER_COLOR_ATTACHMENT_READ|SYNC_FRAGMENT_SHADER_DEPTH_STENCIL_ATTACHMENT_READ|SYNC_FRAGMENT_SHADER_INPUT_ATTACHMENT_READ|SYNC_EARLY_FRAGMENT_TESTS_DEPTH_STENCIL_ATTACHMENT_READ|SYNC_EARLY_FRAGMENT_TESTS_DEPTH_STENCIL_ATTACHMENT_WRITE|SYNC_LATE_FRAGMENT_TESTS_DEPTH_STENCIL_ATTACHMENT_READ|SYNC_LATE_FRAGMENT_TESTS_DEPTH_STENCIL_ATTACHMENT_WRITE|SYNC_COLOR_ATTACHMENT_OUTPUT_COLOR_ATTACHMENT_READ|SYNC_COLOR_ATTACHMENT_OUTPUT_COLOR_ATTACHMENT_WRITE|SYNC_SUBPASS_SHADER_HUAWEI_INPUT_ATTACHMENT_READ, command: vkCmdPipelineBarrier, seq_no: 45, reset_no: 129).

1. Improves stencil handling: - Adds surface type detection to distinguish between color, depth, stencil, and depth-stencil formats - Only enables stencil load/store operations for surfaces that actually contain stencil data - Avoids unnecessary stencil operations for non-stencil formats (DONT_CARE) 2. Fixes read-after-write (RAW) synchronization hazards: - Adds a subpass self-dependency (subpass 0 → subpass 0) - Synchronizes color/depth writes with subsequent shader reads - Uses VK_DEPENDENCY_BY_REGION_BIT for efficient synchronization - Covers all possible relevant stages, • src: Color output + Early/Late fragment tests • dst: Fragment shader • Access: Write → Read transitions here is what hazard looks like [1147.550616] Render.Vulkan <Critical> video_core/vulkan_common/vulkan_debug_callback.cpp:DebugUtilCallback:55: Validation Error: [ SYNC-HAZARD-READ-AFTER-WRITE ] Object 0: handle = 0x7409630000000192, type = VK_OBJECT_TYPE_IMAGE_VIEW; | MessageID = 0xe4d96472 | vkCmdDrawIndexed: Hazard READ_AFTER_WRITE for VkImageView 0x7409630000000192[], in VkCommandBuffer 0xb400007cb003ea70[], and VkPipeline 0x44d3470000000213[], VkDescriptorSet 0x0[], type: VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, imageLayout: VK_IMAGE_LAYOUT_GENERAL, binding #2, index 0. Access info (usage: SYNC_FRAGMENT_SHADER_SHADER_SAMPLED_READ, prior_usage: SYNC_IMAGE_LAYOUT_TRANSITION, write_barriers: SYNC_FRAGMENT_SHADER_COLOR_ATTACHMENT_READ|SYNC_FRAGMENT_SHADER_DEPTH_STENCIL_ATTACHMENT_READ|SYNC_FRAGMENT_SHADER_INPUT_ATTACHMENT_READ|SYNC_EARLY_FRAGMENT_TESTS_DEPTH_STENCIL_ATTACHMENT_READ|SYNC_EARLY_FRAGMENT_TESTS_DEPTH_STENCIL_ATTACHMENT_WRITE|SYNC_LATE_FRAGMENT_TESTS_DEPTH_STENCIL_ATTACHMENT_READ|SYNC_LATE_FRAGMENT_TESTS_DEPTH_STENCIL_ATTACHMENT_WRITE|SYNC_COLOR_ATTACHMENT_OUTPUT_COLOR_ATTACHMENT_READ|SYNC_COLOR_ATTACHMENT_OUTPUT_COLOR_ATTACHMENT_WRITE|SYNC_SUBPASS_SHADER_HUAWEI_INPUT_ATTACHMENT_READ, command: vkCmdPipelineBarrier, seq_no: 45, reset_no: 129).

wildcard added 2 commits 2025-08-09 22:36:15 +02:00

Fix VUID error 02816 c93ba3f4ca

[ VUID-vkCmdPipelineBarrier-dstAccessMask-02816 ] The Vulkan spec states: The dstAccessMask member of each element of pMemoryBarriers must only include access flags that are supported by one or more of the pipeline stages in dstStageMask, as specified in the table of supported access types. Fixes the said validation error.

revert c93ba3f4ca 5a4e0cce21

revert Fix VUID error 02816

[ VUID-vkCmdPipelineBarrier-dstAccessMask-02816 ] The Vulkan spec states: The dstAccessMask member of each element of pMemoryBarriers must only include access flags that are supported by one or more of the pipeline stages in dstStageMask, as specified in the table of supported access types. Fixes the said validation error.

Shinmegumi force-pushed fixRAWsyncerror from cb48dcc858 to 8cb82b8919

2025-08-12 17:13:26 +02:00

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Shinmegumi force-pushed fixRAWsyncerror from 8cb82b8919 to d3558b794d

2025-08-13 15:40:48 +02:00

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