tree 4bb0eb19eb92db3cf9498fb471b00bb3abdb21f2
parent bcdea3b51f0cfd262ac4eb889ae19dc5d98fd24d
author scotttodd <scotttodd@google.com> 1593041375 -0700
committer Scott Todd <scotttodd@google.com> 1593187866 -0700

Control timeline semaphore emulation at runtime, remove extension layer.

* The `VK_LAYER_KHRONOS_timeline_semaphore` extension layer may still be used, but it is no longer required. To simplify maintenance, this change removes IREE's build system helpers and documentation for it.
* The `integrations/tensorflow/e2e/e2e_control_flow_test_tf_iree_vulkan` test required bumping `kMaxInFlightFenceCount` to remain passing when using IREE's new timeline semaphore emulation.
* Updated SwiftShader instructions on Windows now that the Linux-only extension layer is not required with it.