Use a threadgroup memory argument for any workgroup variable that
contains a matrix.
The generator now provides a list of threadgroup memory arguments for
each entry point, so that the runtime knows how many bytes to allocate
for each argument.
Bug: tint:938
Change-Id: Ia4af33cd6a44c4f74258793443eb737c2931f5eb
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/64042
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
Commit-Queue: James Price <jrprice@google.com>