Commit Graph

3 Commits

Author SHA1 Message Date
John Stiles
2654187396 Eliminate unused local variables during SkSL optimization.
This can eliminate const variables which have been completely folded
away, unnecessary synthetic variables created during codegen/inlining,
or code that simply didn't need to exist at all.

Change-Id: I37a65e455e6527a6a6c2f4dde918f48d84dc2638
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/383496
Commit-Queue: John Stiles <johnstiles@google.com>
Reviewed-by: Ethan Nicholas <ethannicholas@google.com>
2021-03-16 17:22:53 +00:00
John Stiles
7a3f5506b6 Performance experiment: disable control-flow analysis.
This CL will be used to test for potential performance regressions (or
improvements) that we might cause by disabling this optimization pass.

It will be reverted in ~1 day.

Change-Id: I26b7687c341eb6d81231406381c39869cfccf6d6
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/381259
Auto-Submit: John Stiles <johnstiles@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
Reviewed-by: Ethan Nicholas <ethannicholas@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
2021-03-08 19:41:19 +00:00
John Stiles
28054added Optimize ternary tests that check a const variable.
This enables the ternary to be optimized away in code like:
   const bool SHINY = true;
   color = SHINY ? add_shine(x) : x; // to --> `color = add_shine(x);`

Without constant propagation.

Also, I added a unit test for ternary expression simplification; I
wasn't able to find an existing one.

When the optimization flag is disabled, this CL actually removes the
optimization of `true ? x : y` --> `x` entirely; previously, this
substitution would be made regardless of optimization settings.

Change-Id: I93a8b9d4027902d35f8a19cfd6417170b209d056
Bug: skia:11343
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/379297
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
2021-03-05 21:41:05 +00:00