This is a major reworking of this transform. The old transform code
was getting unwieldy, with part of the complication coming from the
handling of multiple return statements. By generating a wrapper
function instead, we can avoid a lot of this complexity.
The original entry point function is stripped of all shader IO
attributes (as well as `stage` and `workgroup_size`), but the body is
left unmodified. A new entry point wrapper function is introduced
which calls the original function, packing/unpacking the shader inputs
as necessary, and propagates the result to the corresponding shader
outputs.
The new code has been refactored to use a state object with the
different parts of the transform split into separate functions, which
makes it much more manageable.
Fixed: tint:1076
Bug: tint:920
Change-Id: I3490a0ea7a3509a4e198ce730e476516649d8d96
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/60521
Auto-Submit: James Price <jrprice@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: James Price <jrprice@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
This uses FXC compilation failure mitigation for _any_ vector index assignment that has a non-constant index. FXC can still fall over if the loop calls a function that performs the dynamic index.
Use some vector swizzle logic to avoid branches in the helper.
Fixed: tint:980
Change-Id: I2a759d88a7d884bc61b4631cf57feb4acc8178de
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/57882
Auto-Submit: Ben Clayton <bclayton@google.com>
Commit-Queue: Antonio Maiorano <amaiorano@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Antonio Maiorano <amaiorano@google.com>
James Price
Ben Clayton