commit 2d1be5b80d20bc31830243340bc65f25ff9ea097
author Aske Simon Christensen <askesc@google.com> Mon Nov 07 11:57:03 2022 +0000
committer Commit Queue <dart-scoped@luci-project-accounts.iam.gserviceaccount.com> Mon Nov 07 11:57:03 2022 +0000
tree 0ea9c6e22a2e100a89508d25ffa00e616be232ad
parent d27ea35cccc7c6cc8305fab99ebfeba1f9563be5

[dart2wasm] Consolidate workarounds for type mismatches

In a various places in the compiler, we have had situations with
type mismatches that prompted workarounds.
These fell into a number of cases:

- Calls of functions with return type `Null` or `Never`. These were
  treated like `void` and given no output types. This is now fixed, so
  `Null` or `Never` in return types are just translated to their Wasm
  representations, currently `(ref null #Top)`, later (when we add the
  Wasm bottom types) `(ref null none)`.
- No-value `return` statements in `sync*` functions. Since we don't
  support `sync*`, it's fine that these are broken.
- Constants passed directly to imported functions, or returned from
  exported functions, such that the expected type is `externref`.
  A special case is added for this.
- Constants produced by the TFA constant propagation in places where
  they are incompatible with the context type (e.g. `null` in non-
  nullable context). This is now handled generally in constant
  instantiation and assumed to be always unreachable.

Change-Id: I43915db1b0c91ce0933a16bf36d6108a9cf390f4
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/268001
Reviewed-by: Ömer Ağacan <omersa@google.com>
Commit-Queue: Aske Simon Christensen <askesc@google.com>