Commit Graph
226 Commits
Author SHA1 Message Date
Dana Jansens 6dbcc78e6c Rewrite symbolic constants in generic redeclarations (#5154)
When a generic function declaration was encountered for the second or
more time, we would FinishGenericRedecl() for the function decl, but
this just popped the generic region stack and moved on.

The issue with that is when the stack entry is gone, we lose the
symbolic constants from that declaration, and are unable to rewrite them
to point to the actual generic. This left us with a function declaration
with abstract symbolic values that were not useful, and in a function
call we use the declaration attached to the definition, which would be a
declaration with broken symbolic values. Then the function would be
uncallable since deduce would be unable to determine argument types
without the generic bindings.

This resolves the issue for functions, as well as ensuring the correct
generic id from a previous declaration is used for other generic entity
types that have redeclarations.

When a function declaration is qualified, such as defining a class
method outside the class body, we need only the function declaration to
contribute to its generic region stack. The code was collecting constant
values from all qualifier segments together incorrectly.

So when we PushNameQualifierScope(), we also drop the current generic
region stack and rewrite its constant values by calling
FinishGenericRedecl(), and open a new stack entry for the next part of
the qualified declaration.

If a generic declaration somehow has more dependent instruction than a
previous declaration, it would add new instructions to its eval block
with indices beyond the elements in the actual declaration eval block,
since we only store the block from the first declaration found. To avoid
this we plumb through that we are in a redeclaration, and terminate with
an ICE instead of adding new instructions to crash on later.

Fixes #5136.
2025-03-21 22:26:08 +00:00
Jon Ross-Perkins 868efb7c86 Make INCLUDE-FILE less sensitive to path changes (#5159)
It's helpful for stability to not have the path in the repo reflected in
test files, something I'm separately running into. So to reduce this,
align INCLUDE-FILE with other split behavior:

- Use the filename (with a "include_files/" subdir to disambiguate),
rather than the full path.
- Note if we eventually want to support splits in these, the same
approach could be extended.
- Only provide as an arg if the user requests files as args.

Factoring AddFile back because it's hard to share; I'm also advocating
to remove the prelude manifest, which would mean the remaining call
could be removed.
2025-03-21 16:03:25 +00:00
Dana Jansens b10c1ccbb9 Look through FacetAccessType and FacetValue self types in impl lookup (#5160)
If a self type is FacetAccessType, we look through it at the facet
value, both for the query and the impl declaration. This ensures that
while FacetAccessTypes match each other for constant value equality
still, they an also match with facet value queries, such as:
```
impl forall [T:! Y] T as Z {}
                    ^ FacetAccessType for BindSymbolicName of type FacetType(provides Y).

fn F(y:! Y) {
  y as Z;
  ^ Facet value
}
```

Here the facet value and FacetAccessType don't have the same constant
value. Deduction will give the `T!: y` binding the facet value of `y`,
but the `T` in `T as Z` is a FacetAccessType to that binding, which is a
different constant value. Looking through the FacetAccessType gives us
the desired constant value for comparison with the query.

Additionally if the query self value is a FacetValue instruction, look
through that at the underlying type value. Impl lookup is used to
convert from one type or facet value to a new facet value of the desired
facet type. We want facet values to always be able to convert to
everything possible, rather than to have that restricted to just their
current FacetType:
https://github.com/carbon-language/carbon-lang/issues/5137. So this
allows queries such as `(C as Y) as Z` for a class `C` and interfaces
`Y` and `Z`.
2025-03-20 23:47:45 +00:00
josh11bandJosh L d431e1fbf4 Never perform instance binding with implicit Self in an interface (#5121)
Resolves TODO by creating new function `GetAssociatedValue` with the
logic from `PerformCompoundMemberAccess` restricted to the
non-instance-binding case.

---------

Co-authored-by: Josh L <josh11b@users.noreply.github.com>
2025-03-20 04:25:35 +00:00
Richard Smith 584426dfa2 Initial work on support for templates (#5081)
This broadly follows the design described in [this design
document](https://docs.google.com/document/d/1eWW8MTko3PIqxZ32-GhsdaRSYqoDicxMB1VeessMTOg/edit?pli=1&tab=t.0).

Support is provided for only two primitives for now -- simple member
access and type conversion -- to demonstrate the basics of the
functionality.
2025-03-19 20:19:21 +00:00
Richard Smith 4d2cca48c7 Compute a correct SpecificFunction when resolving an indirect call to an impl function (#5116)
When performing a call through an impl witness, the callee that we
type-check against is the function in the interface, so we form a
specific for that callee. However, once the impl witness access
resolves, the eventual callee is a different function -- the function in
the impl -- so this would cause us to form a `SpecificFunction` where
the callee is one function but the specific refers to a different
function.

Address this by adding another instruction, `SpecificImplFunction`, that
takes a function in an impl and a specific for the corresponding
function in the interface, and computes and returns a `SpecificFunction`
referring to the corresponding specific function in the impl, or returns
a direct reference to the function in the `impl` if it's not a generic
function.
2025-03-18 21:26:52 +00:00
Jon Ross-Perkins dfe1c880ea Clean up node kind information for namespaces (#5120)
This flows out of #5084 and trying to reduce UnsafeMake use. It turns
out imports and namespaces were using unexpected node kinds (previously
ImportIntroducer instead of ImportDecl, for example). This fixes and
adds validation.

I was uncertain about whether to just remove the is_convertible check,
since I don't see it as motivating creation of a conversion between
NodeIdOneOf types. So I've just left a TODO for now.
2025-03-18 00:44:18 +00:00
Jon Ross-Perkins 8738497301 Fix parse support for 'fn F[];' (#5135)
According to approved syntax at
https://github.com/carbon-language/carbon-lang/blob/trunk/proposals/p3848.md#syntax-defined,
`fn F[]` without explicit parameters should be valid. This makes it
work, then adds some validation to prevent `class C[]` in check.

Note that for `fn`, positional parameters are a TODO -- but this allows
me to test validation in `fn destroy[]` which is rejected, not just a
TODO.
2025-03-18 00:31:17 +00:00
josh11bandJosh L fb3721df9a Impl lookup allowed for incomplete facet types (#5132)
New planned direction is to not require completeness. Updated comments
to reflect that some care will be needed once named constraints are
supported. Long term plan is [discussed in
#5089](https://github.com/carbon-language/carbon-lang/pull/5089#discussion_r1985908453):

> We have some options. In our last conversation, it sounded like it
would be beneficial for named constraints to have their own witnesses,
with entries in declaration order. This would allow accesses to the
named constraint while it was being defined. So there would be something
of a hierarchy in a facet type witness, with a named constraint taking a
single slot in a facet type witness, independent of its definition.

Co-authored-by: Josh L <josh11b@users.noreply.github.com>
2025-03-15 02:21:49 +00:00
Dana Jansens ce7a0a4d07 Support conversion from facet value to facet value (#5085)
When converting from a facet value (an instruction whose type is
FacetType), we require making a FacetAccessType
to have a type instruction when building the resulting FacetValue.
Otherwise, the conversion is the same for values of type TypeType, and
we relax the convert function to support either.

Corrects the test expectations for converting `Goat as Animal`, a facet
value of type FacetType, into `Eats`, a facet type of type TypeType.
This would be a promotion in the typish hierarchy which is incorrect. We
had an extra case in Convert that was handling this, and it's now
removed. `Animal`, a facet type, does still correctly convert into
`Eats`, a facet type, if `impl Animal as Eats` exists.
2025-03-14 23:58:36 +00:00
Dana Jansens 417b3833e2 Produce helpful diagnostics when converting to a facet fails (#5109)
When converting to a facet there are three different failure modes:

1. You provided a non-type value. Only types can convert to facets. So
we tell you that we found a non-type value.
2. You provided a facet type (which has type TypeType) which does not
have witnesses for the the target facet's type. So we tell you that the
type `T` implements `X` but needs to implement `Y`.
2. You provided a (non-facet-type) concrete type (of type TypeType)
which does not implement the target facet's type (which is a FacetType).
So we tell you that we need the type to implement the FacetType but it
does not.
3. You provided a FacetAccessType (which is of type TypeType also, but
we special case this), whose underlying FacetType is not compatible with
the target facet's type. So we tell you that we need the type to
implement `X` but found a FacetAccessType `T` which implements `Y`.

Closes #5027
2025-03-14 15:50:03 +00:00
Jon Ross-Perkins db21c38550 Use the NameComponent's name_id when making an entity base (#5125)
This changes the SemIR of invalid redeclarations, because previously
they lacked a name. We've avoided this in diagnostics so it doesn't
otherwise come up, but I plan to use it for more easily validating
redeclarations.
2025-03-14 15:27:24 +00:00
josh11bandJosh L 5966fbc758 Get impl witnesses from facets cast to type (#5115)
Addresses a TODO in `impl_lookup.cpp`.

Co-authored-by: Josh L <josh11b@users.noreply.github.com>
2025-03-12 20:55:07 +00:00
Richard Smith 6fd139b805 Renumber inner parameters when checking an impl function against an interface function. (#5113)
This allows the numbering of the parameters to match when checking for a
valid redeclaration. It also prepares us to produce the proper numbering
when generating a thunk.
2025-03-12 13:54:49 +00:00
josh11bandJosh L ebaf62efb9 Associated constants can be used in member function signatures (#5089)
This required allowing incomplete facet types where previously
completeness was required. Once we support named constraints, we will
need a way to consistently go from an interface to a facet type witness
index without requiring the interface to be complete in these cases.

---------

Co-authored-by: Josh L <josh11b@users.noreply.github.com>
2025-03-12 00:33:46 +00:00
Jon Ross-Perkins 10eb8ed314 Reuse a merged function's type ID (#5099)
This makes inline and out-of-line functions produce the same type.

I was looking at this and wasn't sure if it was deliberate. It seems
desirable to reuse the type when possible, since it's probably cheaper
too.
2025-03-11 16:21:57 +00:00
Dana Jansens d58b523a5e Add INCLUDE-FILE: and --custom-core for file tests to specify a minimal prelude library (#5080)
The INCLUDE-FILE option is only used in the toolchain tests for now. If
specified in a file test, the given file path is added to the test's
arguments. For toolchain tests this makes the file's package available
to the test. The `--custom-core` command line flag is added to the
driver, which avoids adding the production `Core` package to the command
line. Together, these allow a test to provide their own minimal `Core`
package.

For example, this would replace `Core` with the package and prelude in
`facet_types.carbon`.
```
// INCLUDE-FILE: toolchain/testing/min_prelude/facet_types.carbon
// EXTRA-ARGS: --custom-core
```

To support this:
* //testing knows how to parse INCLUDE-FILE out of the header of a test
file.
* //testing adds the file to the virtual file system, and includes it in
the test's arguments.
* //toolchain/driver grows the --custom-core command line flag to avoid
loading the production `Core` package.

Tests that were creating their own minimal prelude to define BitAnd on
types are now pointed to
toolchain/testing/min_prelude/facet_types.carbon as the prelude. They no
longer need to `import Core` in each test as a result.

Such tests are no longer `no_prelude`, but instead have their own
prelude. So they are moved to a `min_prelude` subdirectory.

Closes #5076
2025-03-10 19:44:50 +00:00
Dana Jansensandjosh11b 4539114c21 Return a set of ImplWitnesses from impl lookup (#5075)
A query facet type may contain multiple required interfaces, in which
case impl lookup should return an ImplWitness for an impl that is used
for each interface in the query. We bundle these together into an
instruction block and return that from impl lookup. The witnesses are in
the same order as the interfaces in the
`CompleteFacetType::required_interfaces`. This allows walking the
`required_interfaces` to find an interface to give an index that can
also be used to grab a witness from this set, or from FacetValue.

FacetValue now has an InstBlockId for the set of witnesses of the
FacetType, instead of a single ImplWitness instruction id.

FacetAccessWitness includes the index of the witness (determined from
the position in `required_interfaces`) of the witness it's accessing
from the FacetType.

The
toolchain/check/testdata/facet/no_prelude/fail_todo_call_combined_impl_witness.carbon
test demonstrates the fix in the resulting SemIR. We can see the calls
to methods on a multi-interface FacetType result in a FacetAccessWitness
with an index of the correct interface, and this results in a witness
that leads to the correct impl's function.

There is a TODO in member access, where it does not have a
`CompleteFacetType` yet, so it uses the index in
`FacetTypeInfo::impls_constraints` instead, but this can be incorrect in
the presence of named constraints, which when completed can add more
interfaces to the `CompleteFacetType` and which are sorted into an
arbitrary order with the rest there.

---------

Co-authored-by: josh11b <15258583+josh11b@users.noreply.github.com>
2025-03-10 16:00:35 +00:00
josh11bandJosh L b3be298f7f Fix test that used i32 in a no_prelude directory (#5086)
Exclude SemIR since the point of the test is that it diagnoses something
invalid, not that any particular SemIR is produced.

Co-authored-by: Josh L <josh11b@users.noreply.github.com>
2025-03-08 06:18:18 +00:00
Alina Sbirlea 7fd54eded0 Reverse nesting of BoundMethod and SpecificFunction. (#5079)
During SemIR, when identifying a specific in a specific context, we'd
have to either look through a specific or through a bound method.
Canonicalize which one to look through first, by having the BoundMethod
created around a SpecificFunction instead.
This changes a lot of check tests.

TODO: As the SemIr does not currently allow removal (access to insts()
is intentionally const), the bound instruction created prior to finding
the specific is not removed from the instructions.
Options: (1) leave as is, (2) add a way to remove the previous bound,
(3) rethink how/when the BoundMethod inst is created.
2025-03-08 01:34:06 +00:00
josh11bandJosh L aa90ab3862 Fix non-instance compound member access (#5059)
Implements the rule:

> For compound member access `a.(b)` where `b` names a _non-instance_
member of an interface `I`:
> * `a` is implicitly converted to `I`
> * let `T` be the result of symbolically evaluating the converted
expression
> * `impl` lookup is performed for `T as I`.
>
> Instance binding is never performed.

See
https://docs.carbon-lang.dev/docs/design/expressions/member_access.html#impl-lookup-for-compound-member-access.
Before this PR, non-instance members were treated as instance members.

---------

Co-authored-by: Josh L <josh11b@users.noreply.github.com>
2025-03-07 01:37:07 +00:00
Geoff RomerandRichard Smith 6d4f2567a7 Add support for var patterns (#5069)
Co-authored-by: Richard Smith <richard@metafoo.co.uk>
2025-03-06 19:06:51 +00:00
Geoff Romer f08e046d9e Update text representation of CallParamIndex to match new name (#5067) 2025-03-04 23:28:42 +00:00
Geoff Romer d264f14027 Clean up handling of Call params (#5061)
- Explicitly document that `*Param` and `*ParamPattern` insts represent
`Call` parameters.
- Stop wrapping compile-time parameter patterns in `ValueParamPattern`
insts (because they aren't `Call` parameters).
- Document how `MatchContext::results_` relates to the `Call`
parameters, and be more consistent about when it's written to.
- Remove `RuntimeParamIndex::Unknown`: we no longer need to distinguish
"this `Param`'s runtime index is unknown" from "this `Param` isn't a
runtime param", because we no longer use `Param`s at all in the latter
case.
- Rename `RuntimeParamIndex` to `CallParamIndex`.

As a side effect of removing the `ValueParamPattern` insts, this fixes a
minor diagnostic bug where `NoteInitializingParam` didn't identify the
specific parameter that led to a deduction failure, because it expects
generic parameters to only be represented by `SymbolicBindingPattern`s,
but before this change they could be wrapped in `ValueParamPattern`s.
2025-03-04 21:01:59 +00:00
josh11bandJosh L c2281d1250 Update tests for upcoming #5059 and #5060 on member access and finding impl witnesses in facets (#5054)
Here are some test changes so the diffs that come from my upcoming
functionality changes are easier to see. Upcoming functionality
includes:
* Compound member access with non-instance associated constants will
change to comply with the design
https://docs.carbon-lang.dev/docs/design/expressions/member_access.html#impl-lookup-for-compound-member-access
in #5059 .
* Impl lookup will add support for finding impl witnesses in facets
#5060

I'm also making the toolchain/check/testdata/impl/compound.carbon test
into a no_prelude version, and adding a version that tests with
importing.

---------

Co-authored-by: Josh L <josh11b@users.noreply.github.com>
2025-03-04 17:59:30 +00:00
josh11bandJosh L 900052fcf1 Clarify conversion diagnostic (#5052)
TODO to resolve whether it should conditionally say "object of"
depending on the category

---------

Co-authored-by: Josh L <josh11b@users.noreply.github.com>
2025-03-03 22:09:48 +00:00
Boaz Brickner 28de6c9b7d Add --no-dump-sem-ir to all name_poisoning tests (#5053)
Follow up of previous PR discussions
([#4950](https://github.com/carbon-language/carbon-lang/pull/4950/files/89c2e66dc3190159e2f8d94c31bff31bdd0d81a1..a1650a7d73c8f4013b4b77e4d7d60933f1f6d676#r1972257889),
[#4987](https://github.com/carbon-language/carbon-lang/pull/4987/files#r1964105413)).
Part of #4622.
2025-03-03 19:25:55 +00:00
Boaz Brickner 43b9969058 Split impl/no_prelude/name_poisoning.carbon to interface/no_prelude/name_poisoning.carbon and move interface tests there (#5031)
See
https://github.com/carbon-language/carbon-lang/pull/4950#discussion_r1972252460.
Part of #4622.
2025-02-28 08:06:13 +00:00
Richard Smith 0d2f364f39 Split evaluation up into one function per instruction kind (#5008)
Replace the large and growing `TryEvalInstInContext` function with one
function per kind. While we still have special-case handling for a small
number of instruction kinds, most instructions are now handled either
fully automatically or use a common codepath that evaluates the
instruction operands and then performs an eval-context-independent
evaluation of the instruction.

To support this, `InstConstantKind` is expanded to describe more
fine-grained details about how each kind of instruction interacts with
constant evaluation. Also, the operand kinds of instructions become
slightly more fine-grained: we now distinguish between operands that
describe the destination of an initializing expression (`DestInstId`)
from other `InstId` operands, because `DestInstId` operands need
different treatment during constant evaluation. In particular, an
initializing expression can have a constant value even if its
destination is non-constant or has not yet been set, because evaluation
of an initializing expression doesn't include the store to the
destination.

Some minor test changes:

- We now more consistently propagate errors into the results of constant
evaluation, so more instructions that depend on errors have a constant
value of `<error>`.
- Diagnostic location for invalid array types now point at the whole
array type rather than the array index expression, because
`EvalConstantinst` doesn't have access to the original expression.
- Diagnostic for failed `RequireCompleteType` doesn't print the original
type any more because `EvalConstantInst` doesn't have access to the
original expression.

As a follow-up, some of this -- in particular, the `EvalConstantInst`
overloads -- will be moved to a separate file, in an effort to split the
overall constant evaluation machinery apart from the logic to evaluate
each individual kind of instruction.
2025-02-27 01:31:26 +00:00
Dana Jansens 0beda27192 Fingerprint impl blocks in semir (#5021)
This avoids the suffix changing when adding new impls to the prelude, or
in user code.
2025-02-26 22:47:57 +00:00
3ebd098597 Completing a type no longer ignores facet types (#5004)
Make facet types complete like other types. This means that in the body
of an interface, the type of `Self` is incomplete. This involved fixing
an issue where eval of a specific_id that was already canonical was not
resolving the specific declaration, which could occur as part of
substituting into a facet type.

---------

Co-authored-by: Josh L <josh11b@users.noreply.github.com>
Co-authored-by: Richard Smith <richard@metafoo.co.uk>
Co-authored-by: Dana Jansens <danakj@orodu.net>
2025-02-22 21:40:43 +00:00
Geoff RomerandJon Ross-Perkins 74e1a9949f Support tuple patterns outside parameter lists (#4923)
Parameter lists need substantially different treatment than tuple
patterns in other contexts, so this change splits them into separate
parse node kinds.

---------

Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
2025-02-20 03:17:45 +00:00
eb69d7420e First iteration of completing and resolving facet types (#4920)
* Add `RequireCompleteFacetType` and `ResolveFacetTypeImplWitness` to
`check::Context`. Goal was to move code from `impl.cpp` (mostly) without
functional changes.
* Complete type information is cached with the facet type, and is stored
in a `complete_facet_types()` table.
* Main functional change is to diagnose attempts to use a rewrite
constraint on an associated function. Some existing diagnostics have
been updated.
* Remove `check::Context::RequireDefinedType`:
  * For class types, use `RequireCompleteType`
  * For facet types, use `RequireCompleteFacetType`
* Introduce a `SemIR::SpecificInterface` to hold an interface and
specific id pair.
* Keep the specific interface ids in the impl object.
* Avoid some extra copies in `Dump` functions.
* Future work missing from this PR:
  * Resolving for member access or actions that require impl lookup.
  * Resolving rewrites constraints that refer to non-concrete values.
* Any support for adding implied constraints that result from a `where`
clause (though TODOs have been added).

---------

Co-authored-by: Josh L <josh11b@users.noreply.github.com>
Co-authored-by: Richard Smith <richard@metafoo.co.uk>
Co-authored-by: Dana Jansens <danakj@orodu.net>
2025-02-19 22:10:11 +00:00
Boaz Brickner 6a99c4e970 When diagnosing a duplicated name, add the name to the diagnosis (#4902)
In order to have the name available for diagnostics, we now always set
`NameId` in `NameContext` and put `poisoning_loc_id` as part of the
union with `resolved_inst_id` instead (since we never need both).
2025-02-19 07:19:23 +00:00
Richard Smith e0b2f5d772 Add and propagate template phase for constants. (#4964)
Treat template bindings as introducing template phase, and propagate it
in the same way we propagate the checked generic phase.

Rename "symbolic" to "checked symbolic" to make room for "template
symbolic". Also rename "phase" to "dependence".
2025-02-18 18:57:34 +00:00
Dana Jansensandjosh11b 382094b725 Support conversion of facet-ish values for type deduction (#4956)
A value of type FacetAccessType can convert to a facet value of a target
FacetType if the value's underlying facet value's FacetType is 
compatible.

A value of type FacetType can convert to another value of type FacetType
if the value's FacetType is compatible with the target FacetType.

During impl lookup, the comparison of the lookup type and the impl's
type needs to consider more than strict equality. If the impl's self
type is a FacetAccessType, we instead need to verify that the FacetType
of the lookup type and of the impl's self type are compatible (which is
like a problem of another impl lookup). For now we check that they are
equal by unwrapping the FacetAccessType to the constant facet value
within, and compare that with the lookup type.

---------

Co-authored-by: josh11b <15258583+josh11b@users.noreply.github.com>
2025-02-18 18:14:03 +00:00
Boaz Brickner 4a93b6667e Add the used name to the NameUseBeforeDecl diagnostic (#4901)
Part of #4622.
2025-02-14 21:54:35 +00:00
Boaz Brickner dd7c64bad0 When diagnosing a duplicate name, point to the name instead of the instruction (#4953)
Left TODOs where more work is necessary before this change can be
applied or its impact can be verified.

Includes #4952, to avoid regression in some cases.

Similar to #4938. See
https://discord.com/channels/655572317891461132/655578254970716160/1339007384361762857.
2025-02-14 19:21:50 +00:00
Boaz Brickner 986a2a064c Add poisoned names to the format (#4961)
Part of #4622.
2025-02-14 19:18:51 +00:00
Richard Smith 6dda094928 Superficial support for template modifier on symbolic bindings. (#4948)
Change parse tree from `template (T:! type)` to `(template T):! type`,
so that we have information about whether a binding is a template
binding available when forming the representation of the binding
pattern. This incidentally fixes a bug that we would accept `template
addr A:! B` instead of the intended `addr template A:! B`.

Track whether a symbolic binding is a template binding on the
`EntityName` object. I'm borrowing a bit from the `CompileTimeBindIndex`
for this in order to avoid making `EntityName`s larger. Longer-term, we
should think about using a different representation for symbolic
bindings, to avoid including these fields in all `EntityName`s, but
that's out of scope for this change.

So far, template bindings are treated as having the same phase as
checked bindings, but that will change in a future PR.
2025-02-13 02:15:22 +00:00
Richard Smith c6d35e1c4a Rename template constant -> concrete constant. (#4939)
This implements a direction decided in a
[recent
discussion](https://docs.google.com/document/d/1Iut5f2TQBrtBNIduF4vJYOKfw7MbS8xH_J01_Q4e6Rk/edit?resourcekey=0-mc_vh5UzrzXfU4kO-3tOjA&tab=t.0#heading=h.mas1g68xx9ct)
to switch away from "template constant" when naming a constant that
doesn't depend on any generic parameters, because that creates confusion
with template-dependent constant values that depend on a template
parameter.
2025-02-12 21:24:51 +00:00
Boaz Brickner 1aa6573d4e When diagnosing poisoned name, point to the declared name instead of the entire declaration (#4938)
See
https://discord.com/channels/655572317891461132/655578254970716160/1339007384361762857.

Part of #4622.
2025-02-12 20:59:55 +00:00
Dana Jansensandjosh11b f3a898bac0 Support implicit conversion from a type value to a facet value (#4863)
If a type satisfies the requirements of a FacetType, then that type as a
value can be converted to a FacetValue, which binds the type value to
the FacetType.

For instance, if the class A implements an interface B, then
```
  fn F(b:! B) {}
```
can be called with the type `A`
```
  F(A);
```
This does not handle yet receiving non-type values matching a FacetType,
as that requires deducing the required FacetValue for the caller's
argument. Follow-up work will do this step.

---------

Co-authored-by: josh11b <15258583+josh11b@users.noreply.github.com>
2025-02-06 18:56:32 +00:00
Richard Smith d71b84438f Add a writeup for how associated constants are processed. (#4856)
Also fix a bug found when working through this.
2025-02-05 01:28:25 +00:00
Richard SmithandJon Ross-Perkins fcfb1345d5 Support accessing associated functions by member access into facets (#4872)
For an expression such as `(Type as Interface).AssocFn()`, track the
`Self` type `Type` in the result of the member access so that it's
available when checking the function call.

This introduces a new kind of type, `ImplFunctionType`, that represents
the type of a function that is expected within an impl, modeled as the
type of the function within the interface plus a value to use as `Self`.
Calls to values of this type behave like calls to the underlying
function except that the `Self` parameter is pre-bound to the self type
from the facet.

In order to support this, fix an issue where the imported list of
generic bindings lost their association with their enclosing generic.
This adds a little complexity to `import_ref`, including a new recursive
cycle that I intend to address in a follow-up PR.

---------

Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
2025-02-04 22:38:38 +00:00
Boaz Brickner c67920e631 When diagnosing name used before declared, set the location of the usage (#4860)
Done by adding a poisoning location for each poisoned name.
Part of #4622.
2025-02-03 20:01:09 +00:00
Boaz Brickner 7c01bb4e5c Return the NameId for a new instruction regardless if it's unresolved because it's poisoned or not (#4861)
i.e. Support `Poisoned` in `NameContext::name_id_for_new_inst()`.
Part of #4622.
2025-01-29 14:20:05 +00:00
Richard Smith 5f888e1124 Treat associated constants as entities parameterized by Self (#4837)
Add a full entity representation for associated constants, and build a
`Generic` object for them. This `Generic` is parameterized by the
enclosing `Self` type, allowing the use of `Self` within the type of the
associated constant to be supported.

When performing impl lookup for an associated constant, produce the type
with the provided self type substituted for its `Self` along with any
generic parameters of the interface.

Split the handling of associated constant declarations into two parts,
corresponding to the code before the `=`, and the code between the `=`
and `;` (if any). The former goes into the generic declaration region;
the latter into the generic definition region. This prepares us to
handle the default value for an associated constant, but for now we're
just storing the information and not actually using it.

Remove the entity type field from `assoc_entity_type`, because it's
almost unused and is an attractive nuisance -- it must necessarily be a
type in the generic scope of the associated constant rather than in the
scope of the instruction (because there is no `Self` anywhere else),
which means that it's hard to substitute into or derive meaning from.

See `toolchain/check/testdata/impl/assoc_const_self.carbon` for tests of
the new functionality; these used to cause the toolchain to crash.
2025-01-25 02:13:52 +00:00
Jon Ross-Perkins 6b5eb1a101 Id::Invalid -> Id::None (#4834)
High level, replacing `Id::Invalid` with `Id::None` and `Id::is_valid`
with `Id::has_value` for clarity, as discussed
[here](https://discord.com/channels/655572317891461132/655578254970716160/1331664574545395794).
The `IntId` refactoring is needed together with `AnyIdBase` because it's
also used with `ValueStore`.

Note, trying to be careful not to rewrite `EnumBase::InvalidIndex`, or
`is_valid` in general (e.g., `IdKind::is_valid`).

I've tried to sequence commits here:

1. Automatic replacements:

- `((?:Id|Index)(?: |::|\(|Base(?:\(|::)))Invalid((?:Index)?\W)` ->
`$1None$2`
  - `<invalid>` -> `<none>`
  - `InvalidNodeId` -> `NoneNodeId`
  - `/\*invalid\*/` -> `/*none*/`
  - `id((?:_|\(\))(?:\.|->))is_valid` -> `id$1has_value`

2. Manual edits:

  - In `int.h` and `int_test.cpp`
    - `IntT` has `is_value`, which I'm renaming to `is_embedded_value`.
    - Manual edits to comments in this file.
  - `AnyIdBase` and `IdBase`
- Declaration of `is_valid` -> `has_value`, `InvalidIndex` ->
`NoneIndex`.
  - In `ids.h` and `ids.cpp`
    - `is_valid` -> `has_value`
- `// An explicitly invalid ID.` -> `// An ID with no value.`; similar
for index
    - Various math on `InvalidIndex` -> `NoneIndex`
    - Various mentions of "valid" in comments
  - In `value_store.h`, for `IdT::Invalid`, plus one comment
- In `impl.h` and `tokenized_buffer.h`, we had different initialization
of `::None` values (versus `ids.h` syntax) that I fixed manually.
  - Spot checks to compile
- Particularly where `is_valid` replacements didn't catch spots due to
different naming.

3. Autoupdate tests

4. verbose.carbon (NOAUTOUPDATE)

5. Comment spot checks

Note there are probably other mentions of "Invalid" that should be swept
up, but I'd like to argue for merging and separating out remaining
cleanup since this is so sweeping (and likely to hit merge conflicts
from churn). We'll probably have lingering mentions of "invalid" for a
bit regardless, just because there are uses of "invalid" in non-Id APIs.
2025-01-22 23:15:00 +00:00
Calvin 3f4de65ad8 Improve SemIR naming of import_refs (#4824)
Changes the name of SemIR `import_ref`s to use the format
`<package>.<entity>`.

<table>
<tr><th>Before</th><th>After</th></tr>
<tr>
<td><code>%import_ref.05a: type</code></td>
<td><code>%Main.D: type</code></td>
</tr>
<tr>
<td><code>%import_ref.8f2: &lt;witness&gt;</code></td>
<td><code>%Main.import_ref.8f2: &lt;witness&gt;</code></td>
</tr>
</table>

* [Discord discussion in
#toolchain](https://discord.com/channels/655572317891461132/655578254970716160/1330253540999827577)
* Closes #4769
2025-01-22 07:22:07 +00:00