ImplWitness (#4679)

* Change `InterfaceWitness` -> `ImplWitness`
* Include a `SpecificId` in the `ImplWitness`. This allows the
`InstBlock` it contains to have its own identity, allowing it to be
changed as the impl is processed. Evaluation only updates the specific.
* Create the `ImplWitness` at the start of the impl definition. In the
future, this will be populated with the values of non-function
associated constants. For now, it starts full of invalid instruction
ids.
* Implements the model suggested in #4672 .

Note that the non-SemIR testdata changes are to these file:
* `toolchain/check/testdata/impl/lookup/fail_todo_undefined_impl.carbon`
* `toolchain/check/testdata/struct/import.carbon`
* `toolchain/check/testdata/tuple/import.carbon`

The last two are due to an import of generics bug exposed by this PR,
which will be fixed in a follow-on.

---------

Co-authored-by: Josh L <josh11b@users.noreply.github.com>
Co-authored-by: Richard Smith <richard@metafoo.co.uk>
This commit is contained in:
josh11b
2025-01-02 23:03:11 +00:00
committed by GitHub
co-authored by Josh L Richard Smith
parent 4a7aefefaa
commit c5fd8f42b8
256 changed files with 3060 additions and 2616 deletions
+1 -1
View File
@@ -261,7 +261,7 @@ static auto BuildFunctionDecl(Context& context,
if (function_info.is_extern && context.IsImplFile()) {
DiagnoseExternRequiresDeclInApiFile(context, node_id);
}
function_info.generic_id = FinishGenericDecl(context, decl_id);
function_info.generic_id = BuildGenericDecl(context, decl_id);
function_decl.function_id = context.functions().Add(function_info);
} else {
FinishGenericRedecl(context, decl_id, function_info.generic_id);