3 Commits

Author SHA1 Message Date
Ben Clayton
800b8e3175 optimizations: Implement transform::ShouldRun()
This change adds an override for Transform::ShouldRun() for many of the transforms that can trivially detect whether running would be a no-op or not. Most programs do not require all the transforms to be run, and by skipping those that are not needed, significant performance wins can be had.

This change also removes Transform::Requires() and Program::HasTransformApplied(). This makes little sense now that transforms can be skipped, and the usefulness of this information has been severely reduced since the introduction of transforms that need to be run more than once.
Instread, just document on the transform class what the expectations are.

Issue: tint:1383
Change-Id: I1a6f27cc4ba61ca1475a4ba912c465db619f76c7
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/77121
Reviewed-by: Antonio Maiorano <amaiorano@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Ben Clayton <bclayton@google.com>
2022-01-25 21:36:04 +00:00
Ben Clayton
ed60a9905c transform: LoopToForLoop - fix bad emission
For loops only support assignments or function calls for the continuing statement.

Fixed: tint:1064
Change-Id: I07065b2119e7b9f97ca7e46b1464fd72333ca429
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/60212
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: David Neto <dneto@google.com>
2021-07-29 18:05:19 +00:00
Ben Clayton
5e607680e7 transform: Add LoopToForLoop
A Transform that attempts to convert WGSL `loop {}` statements into a for-loop statement.
For-loops cause less broken behavior with FXC than our current loop constructs.

Bug: tint:952
Change-Id: I0b7b1dbec9df4c004b0419d3feae53a195ec79bb
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/56767
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: David Neto <dneto@google.com>
2021-07-02 22:17:25 +00:00