Commit Graph

2 Commits

Author SHA1 Message Date
John Stiles
986c7fb8ca Fix codegen errors with Metal return statements.
The Metal return type from main() diverges from the SkSL source, so we
patch it in the Metal code generator. This CL improves the patching
process in multiple ways:

- A `return` statement from a fragment processor main() is rewritten to:
    return *_out;

- A `return` statement from a vertex processor main() is rewritten to:
    return (_out->sk_Position.y = -_out->sk_Position.y, *_out);

- We avoid emitting a duplicate `return *_out;` statement if we can
  determine that main() already ends in a return statement. This is
  harmless either way so it doesn't necessarily catch everything. (e.g.
  it doesn't detect an if/else which returns at the end of both blocks.)

Also added a unit test which returns from the middle of a vertex shader,
since we didn't test this anywhere and we need to verify that
sk_Position.y will be negated. (This didn't work properly before.)

Change-Id: I14cf18375894fc712fa6c6466df3888ebaeba7c8
Bug: skia:10903
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/339636
Reviewed-by: Ethan Nicholas <ethannicholas@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
2020-12-01 21:28:05 +00:00
John Stiles
ab4ab20fcf Migrate most SkSL tests currently in /glsl/ to /shared/.
These tests will also be used for Metal and SPIR-V testing. A small
handful of GLSL-specific stragglers (#version-specific or type-precision
related) will remain in /glsl/.

Change-Id: I7f2b2bd92825c327922c8ce74e438d2daa440dff
Bug: skia:10649
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/319408
Commit-Queue: John Stiles <johnstiles@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Ethan Nicholas <ethannicholas@google.com>
2020-09-25 17:13:53 +00:00