tree b220754aeab67572e4814789475190632b9090d8
parent 7b921fb4c778b324d706f78a91d5e047626f2292
author Ben Clayton <bclayton@google.com> 1652997059 +0000
committer Dawn LUCI CQ <dawn-scoped@luci-project-accounts.iam.gserviceaccount.com> 1652997059 +0000

tint: Remove ast::CallExpression -> sem::Call implicit mapping

With abstract materialization, any ast::Expression may map to the new
sem::Materialize node. Because of this, we can't assume that an
ast::CallExpression maps to a sem::Call, as it might be wrapped by a
sem::Materialize.

Remove the mapping, and fix up all the code that was relying on this.

Fixes are done by either:
• Calling `UnwrapMaterialize()->As<sem::Call>()` on the semantic
  expression. This is done when the logic may assume it's possible for
  the expression to be a Materialize node.
• Using the explicit sem::Info::Get<sem::Call>() template argument to
  cast the semantic type to sem::Call. This is done when the logic
  either knows it is impossible for the expression to be a Materialize.

The backends have been stubbed, as we'll want to emit the constant value
for these nodes. It's likely that we'll just use the FoldConstants
transform to strip all Materialize nodes from the tree. For now, be
defensive.

Bug: tint:1504
Change-Id: If9231b300fc30c7fe886c17a804ead8ee2988285
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/90533
Commit-Queue: Ben Clayton <bclayton@chromium.org>
Reviewed-by: David Neto <dneto@google.com>