Commit 3f0c4a56e7b6eaef22cc9f36c90ea2ee4063c587
2019-01-10T10:20:35
Vulkan: Faster state transitions. Implements a transition table from Pipeline Cache entry to state change neighbouring Pipeline Cache entries. We use a 64-bit mask to do a quick scan over the pipeline desc. This ends up being a lot faster than doing a full hash and memcmp over the pipeline description. Note that there could be future optimizations to this design. We might keep a hash map of the pipeline transitions instead of a list. Or use a sorted list. This could speed up the search when there are many transitions for cache entries. Also we could skip the transition table and opt to do a full hash when there are more than a configurable number of dirty states. This might be a bit faster in some cases. Likely this will be something we can add performance tests for in the future. Documentation is also added in a README file for the Vulkan back end. This will be extended over time. Improves performance about 30-35% on the VBO state change test. Bug: angleproject:3013 Change-Id: I793f9e3efd8887acf00ad60e4ac2502a54c95dee Reviewed-on: https://chromium-review.googlesource.com/c/1369287 Commit-Queue: Jamie Madill <jmadill@chromium.org> Reviewed-by: Yuly Novikov <ynovikov@chromium.org>