Simplify redundant pop-push pairs.
It's very common for the code generator to pop from the stack into
a variable, then immediately push the same variable onto the stack
again. We now detect this and eliminate the redundant copy.
Change-Id: If359ed9117a118b70b6b1f06bfc67539f26aa5d8
Bug: skia:13676
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/631241
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
37 files changed
