kc3-lang/angle

2019-01-28T11:39:15

Vulkan: optimize image memory barriers Each image was tracking its current layout, but not the pipeline stage it was used. Additionally, the barrier access masks were inferred from the layout. This incurred two inefficiencies: - The src pipeline stage mask often included all stages, causing unnecessarily heavy barriers. - The access masks included all possible accesses by a layout, which in some cases was overkill, like VK_ACCESS_MEMORY_WRITE_BIT for VK_IMAGE_LAYOUT_GENERAL (which will eventually used for compute shader output). This change instead creates an enum where each element represents the layout, the stage and access masks when transitioning into the layout and the stage and access masks when transitioning out of that layout. The image will instead track a value of this enum (instead of VkImageLayout), which allows it to create the layout transition barriers as tight as possible, since it includes all the necessary information. Bug: angleproject:2999 Change-Id: I91535ce06d10530a6fc217ad3b94b7e288521e25 Reviewed-on: https://chromium-review.googlesource.com/c/1440074 Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org> Reviewed-by: Jamie Madill <jmadill@chromium.org>