kc3-lang/angle

2021-10-26T19:29:44

Vulkan: Don't submit XFB queries when XFB is inactive Consider the following GL commands: glBeginQuery(GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN) glBeginTransformFeedback() glDrawArrays() glPauseTransformFeedback() glDrawArrays() glResumeTransformFeedback() glDrawArrays() glEndTransformFeedback() glEndQuery(GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN) The renderpass is broken for each of the draw calls, leading to pauseRenderPassQueriesIfActive() and resumeRenderPassQueriesIfActive() being called when the RP is stopped/started. This leads ANGLE to generate 3 TransformFeedbackPrimitivesWritten queries when looping through the "active" queries, since no consideration is made for XFB actually being active/unpaused. ARM doesn't support the TransformFeedbackPrimitivesWritten query when XFB is disabled. Instead, the query is never completed and the results are never available. It could probably be argued that this is an ARM bug, and they should just output '0' if XFB isn't active during the query. Regardless, ANGLE shouldn't be issuing the queries when XFB is no active, since it's wasteful. Bug: angleproject:6622 Test: dEQP.GLES3/functional_transform_feedback* Test: TransformFeedbackTest.TransformFeedbackQueryPausedDrawThenResume Change-Id: I380fb60405d7f538b802bb0df72bf609f0bc58e9 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3246532 Reviewed-by: Charlie Lao <cclao@google.com> Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org> Commit-Queue: Tim Van Patten <timvp@google.com>