Commit Graph
198 Commits
Author SHA1 Message Date
Jon Ross-Perkins 95ce06a7a4 Adjust KindHasGetConstantValueOverload approach (#5526)
Tinkering with #5517, splitting out this suggestion to try to avoid
delaying merge. I figured out what I was missing on the variadiac
expansion. :)

(and also realized the struct could probably be a function)
2025-05-23 17:58:08 +00:00
Dana JansensandJon Ross-Perkins 5aea18f949 Avoid resolving the decl block for specifics in imported instructions (#5517)
Move the operation of resolving the specific decl block from
`GetConstantValue()` to `TryEvalTypedInst()`, with is now happening
after replacing the fields of the instruction with new constant values,
but before running the evaluation of the instruction. Since imported
instructions are not evaluated, this avoids resolving the specific decl
block from imported instructions, resolving a TODO in
`AddImportedConstant()`. Now `AddImportedConstant()` can replace
constant values in its fields without having to worry about that
operation resolving any specific decl blocks.

We get to add a new TODO however, to explain why we still need a special
case in resolving specific decl blocks for handling `Impl` construction.
The witness table contains instructions with specifics referring to the
generic self of the impl declaration. But the table must be constructed
before the impl's generic is finished, in order to make the instructions
dependent for the generic. But then resolving the specific decl block
can't be done when the instructions are created and evaluated, as that
requires a finished generic.

---------

Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
2025-05-23 16:58:46 +00:00
Richard Smith 5b884ae14d Improve lowering for global variables. (#5492)
- Track the `VarPattern` instruction on the `VarStorage` instruction so
that it's available for name mangling.
- Mangle global variables based on the first binding name within their
pattern.
- Give global variables external rather than internal linkage, except if
they have no bindings whatsoever in their pattern.
- To support lowering references to bindings nested within a global var,
such as for `var (x: i32, b: i32)`, add some basic initial support for
reference constant expressions. Treat a global `var` as a reference
constant, and treat an aggregate access into a reference constant as a
reference constant.
2025-05-21 00:09:10 +00:00
Jon Ross-Perkins 14f19b5a86 Use TypeEnum for ScopeId to refactor call structure (#5491)
I'm trying to make the offsetting a little easier to understand, and
also get a better `requires` structure on calls. The second is for an
attempt to refactor the `Formatter` API, but also changing the `InstId`
`derived_from` requires seems helpful for clarity on what's really
happening.
2025-05-20 22:16:28 +00:00
Jon Ross-Perkins 27d0d26739 Replace value_kind with has_type, make FormatInstLhs name-dependent (#5501)
InstValueKind is really just wrapping HasTypeIdMember. Rather than
exposing this as an enum, expose it as a bool since it better reflects
what's going on.

In eval.cpp, AddImportedConstant should never be called on an untyped
instruction.

In FormatInstLhs, we can also depend on whether InstNamer has assigned a
name in order to decide whether to print an instruction. This should
avoid some divergence with CollectNamesInBlock.

We also discussed restoring InstValueKind::Untyped, but that's mainly
motivated by the formatter, and the InstNamer approach gives a more
localized implementation.
2025-05-19 23:26:32 +00:00
Jon Ross-Perkins 74c0ed413c Update tool versions beyond just bazel (#5446)
#5445 updates to bazel 8.2.1, this does more updates (including to
buildifier, which does autofixes like the `sh_test` loads in the other
PR).

Note I'm using the latest available clang-format wheel. That's not
really something I expect people to have installed, but should mostly be
consistent. I'm specifically skipping clang-format 18 because it had
some broad regressions, and 19 got really confused by a `requires` on a
trailing return. Using the latest seemed probably okay since most people
won't see the difference. Do note that trailing returns in macros,
https://github.com/llvm/llvm-project/issues/47664, seems to be cropping
up again as an issue.
2025-05-08 16:24:28 +00:00
Richard SmithandDana Jansens 4f5d11a28b Build generic eval blocks incrementally (#5313)
Instead of building an eval block as a separate pass at the end of a
generic, build the eval block incrementally.

The larger change here is that asking for the type or constant value of
an instruction now always returns an unattached type or constant value,
in order to preserve the behavior that we previously achieved by doing
the rewrite to attached types and constant values at the end of handling
the generic.

This also incidentally fixes some subtle issues where attached types and
constant values would leak out into check and cause it to get confused
about differences between attached and unattached values. Check should
no longer see attached values except where it explicitly asks for them.

---------

Co-authored-by: Dana Jansens <danakj@orodu.net>
2025-05-01 20:24:15 +00:00
Dana JansensandJon Ross-Perkins 315e206ff1 Construct LocId from InstId directly (explicitly) instead of doing lookups when possible (#5355)
Remove calls to `InstStore::GetLocId()` to build a LocId from an InstId
now that they can be constructed directly from the InstId. Most uses of
LocId are just plumbing, so this does not affect them. However places
that want to look inside the LocId do not want to work with the InstId
form. In these places, introduce `InstStore::GetResolvedLocId()` which
converts a LocId (or an InstId as an optimization) into a LocId which is
not backed by an InstId. These locations can be printed (they have a
line and column when they are a NodeId), they can have flags added to
them (`ToImplicit`, `ToTokenOnly`), they can be converted to an
underlying ImportIRInstId, or they may be `None`.

`Dump()` is made to print a resolved location instead of printing the
InstId in the location, since (at least in my experience) the resolved
location is what is interesting in debugging, and this saves manual
`MakeInstId` steps in the debugger every time a location is of interest.

The LocId constructor from InstId is made `explicit` to add clarity to
function calls passing an `inst_id` now directly instead of calling
`context.insts().GetLocId(inst_id)`. To avoid needing to construct
`SemIR::LocId(...)` explicitly in all cases though, the diagnostics code
in Check uses `DiagnosticLocId` as its template parameter which accepts
InstId as well and does the construction of LocId from it.

Because LocId now requires an explicit construction from InstId, any
callers to `AddInst()` functions will have to explicitly convert to
LocId if they had an InstId, but not if they pass a NodeId. To make this
difference clear to callers, we `requires` that the input type can be
converted to LocId. This ensures that passing an InstId results in an
error at the callsite where the InstId is passed, instead of generating
a compiler error when trying to construct `LocIdAndInst` inside
`AddInst()`, which is less clear about what went wrong and doesn't seem
entirely intentional.

---------

Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
2025-04-28 19:06:24 +00:00
Richard Smith b5ae988a08 Add builtins for compound assignment operators. (#5335)
Provide builtins for compound assignments instead of defining them in
the prelude as a use of a binary operator and an assignment. This allows
us to lower compound assignment directly to LLVM operations instead of
producing a function call. In the short term this also allows us to
define a type-generic compound assignment in the prelude.
2025-04-21 20:38:11 +00:00
Richard Smith 89c9714825 Fix handling of member types of generic classes. (#5332)
Instead of evaluating a non-parameterized class or interface to a
constant with `SpecificId::None`, use the self specific for that class
or interface, which will not be `None` if there is an enclosing generic.
2025-04-18 15:09:50 +00:00
Dana Jansens c38e723dd8 Rename singleton InstId constants to TypeInstId (#5323)
These constant instructions are all TypeInstId already in their type,
and this makes their names match.

Change the name of MakeSingletonInstId as well and update its comment.
2025-04-17 18:57:20 +00:00
Thomas Köppe bf32da8dad Add missing standard library header inclusions (#5316)
Discovered by clang-tidy.
2025-04-17 15:37:57 +00:00
Jon Ross-Perkins 4923445e3a Drop Singleton from ErrorInst::SingletonInstId and similar (#5304)
We frequently want to operate on singletons. Per discussion, drop
`Singleton` to make the code shorter.

This started off as wanting to write `inst_id.is_error()`, but the
dependency relationship between ids.h and singleton_insts.h would
require some kind of delayed evaluation to allow the implementation to
remain in headers (which I suspect is helpful to have for inlining). I
could have added something like `IsErrorInst`, forward declared in ids.h
and defined in singleton_insts.h (which would always be included by
typed_insts.h), but the template approach felt like a decent balance
between (a) removing the boilerplate `::SingletonInstId`, (b)
understandability, (c) still visually mirroring if we immediately return
a singleton, and (d) flexibility for more than just `ErrorInst`. But TBH
I'd probably still have written `is_error()` if it didn't require
addressing the cross-header cycle.

Then I tried `SemIR::InstId::Is<SemIR::ErrorInst>`, which generally
worked with types but generated the complaint that it didn't shorten
*all* singleton uses. So pulling back on `::Is`, and instead just
dropping `Singleton`.
2025-04-15 22:40:29 +00:00
Jon Ross-PerkinsandChandler Carruth b49e89e97e Add a no-op builtin function which shouldn't generate code. (#5306)
This is part of a broader plan to have noop destructor functions for
trivial destruction.

Note this emits a SemIR call (`%no_op: init %empty_tuple.type = call
%NoOp.ref() [concrete = constants.%empty_tuple]`), but not LLVM IR. My
thought was this was probably okay, since even though it'll be a little
spammy with destructor calls, the flipside is there'll probably already
be a fair amount for the name reference, and this at least shows when
the call is injected (and discarded).

---------

Co-authored-by: Chandler Carruth <chandlerc@gmail.com>
2025-04-15 00:33:39 +00:00
Jon Ross-Perkins 55da026a46 Remove the SemIRLoc typedef (#5299)
Replace SemIRLoc typedef uses with explicitly SemIR::LocId, loc ->
loc_id for consistency.
2025-04-14 14:28:15 +00:00
Dana Jansens f0663715dd Even more usage of TypeInstId (#5296)
Use TypeInstId in many more places where the instruction is required
to/known to always be a type value. This should be a somewhat exhaustive
set of places, as it covers all instructions given to
GetTypeIdFromTypeInstId().

The things of interest here are:

- Singleton instructions are always of type TypeType, so they are now
TypeInstIds.
- ErrorInst::SingletonInstId gets upcast to be an InstId because it's
sometimes used to define the type of a variable (as in `auto inst_id =
SemIR::ErrorInst::SingletonInstId;` that may hold other InstIds.
- Parse nodes don't really know about TypeInstId, so NodeStack::Push
needs to do some special casing to avoid CHECK failures when given a
TypeInstId but expecting an InstId. We leave a TODO behind here because
the nodes which are being pushed a TypeInstId should probably be taught
to expect that, but such a change is a bit tricky, so too much for this
PR.
2025-04-11 21:47:43 +00:00
Dana JansensandRichard Smith 0e8d354567 Split the witness table into a separate ImplWitnessTable instruction (#5272)
This allows us to import the table for a given impl only once, while we
can import many ImplWitness instructions with different specifics for a
generic impl.

For example in convert_facet_value_to_narrowed_facet_type.carbon we see
that a single witness table is imported for the BitAnd interface, with
multiple witnesses (for different specifics) imported and sharing the
same table.

The ImplWitnessTable now contains a back-link to the Impl the witness is
for, allowing inst namer to name that interface in the textual semir,
and allowing the interface to be found when debugging from a witness.

---------

Co-authored-by: Richard Smith <richard@metafoo.co.uk>
2025-04-11 20:30:04 +00:00
Dana JansensandRichard Smith cf57c85545 Introduce TypeInstId (#5288)
TypeInstId is an InstId whose constant value has a type of TypeType.
This includes:
- Type value instructions, the `ClassType` or `IntLiteralType`
instructions.
- Constraint value instructions, which are the `FacetType` and
`TypeType` instructions, each of which also have type TypeType.

TypeInstId encodes in the type system that it is safe to convert the
instruction's value to a TypeId, and CHECKs at construction that this
invariant is maintained.

---------

Co-authored-by: Richard Smith <richard@metafoo.co.uk>
2025-04-10 22:59:02 +00:00
Richard Smith a74ca9071b Remove all remaining uses of TypeIds as instruction operands. (#5280)
In preparation for shifting from `TypeId`s potentially representing
attached types to always representing unattached types, using
[terminology suggested on
Discord](https://discord.com/channels/655572317891461132/963846118964350976/1359286326779973712).
This change causes us to track slightly more type spelling information
through SemIR.

One change that has significant impact on the SemIR output is that we
now build a `struct_type` instruction in each class representing the
types of the fields, including the spelling used for those types. This
is now no longer always identical to the corresponding canonical
`struct_type` for the object representation, so it's built separately
and owned by the class.

Also remove `TypeBlock` support entirely, as its only use was
representing `TupleType`s, which now use an `InstBlock`.
2025-04-10 20:53:42 +00:00
Richard Smith a91752de60 Represent rewrite constraints in FacetTypeInfo with InstId not ConstantId. (#5281)
This follows the pattern used elsewhere, and allows facet types in eval
blocks to directly reference their operands instead of doing so
indirectly via a `ConstantId` attached to the generic. This prepares us
for making `ConstantId`s always be unattached.

In passing, add a stringified version of the `InstId` to diagnostics in
a couple of places where it seems useful.
2025-04-10 03:56:12 +00:00
Richard Smith bfef32b482 Add an EvalOrAddInst function. (#5258)
Use that instead of `AddInstInNoBlock` to get the value of an
instruction when evaluation might depend on the `InstId` but only the
`ConstantId` of the instruction is desired by the consumer.
2025-04-08 21:04:30 +00:00
Richard Smith 0631e18184 Provide an InstId when evaluating a constant in cases where one is needed (#5202)
For each kind of instruction, specify whether its constant evaluation
needs an `InstId` or not. If it does, ensure that all constant
evaluation of that instruction provides one. Otherwise, allow calling
into the evaluator without providing an `InstId`.

This allows us to reliably use the `InstId` in evaluation steps that
either need a location or need to look at the original operands of the
instruction prior to evaluation, and also to support `TryEvalInst` calls
safely for instructions whose evaluation does not need an `InstId`.
2025-04-08 00:40:21 +00:00
4af0c8f8d1 Implement ...where .Self impls... (#5238)
* Also remove facet type deduction, since we decided against it on
[2025-04-02](https://docs.google.com/document/d/1Iut5f2TQBrtBNIduF4vJYOKfw7MbS8xH_J01_Q4e6Rk/edit?pli=1&resourcekey=0-mc_vh5UzrzXfU4kO-3tOjA&tab=t.0#heading=h.95phmuvxog9n).

---------

Co-authored-by: Josh L <josh11b@users.noreply.github.com>
Co-authored-by: Dana Jansens <danakj@orodu.net>
2025-04-07 20:45:45 +00:00
Richard Smith c33adfafd3 Replace GetTypeInSpecific with GetTypeOfInstInSpecific. (#5232)
Reduce usage of `GetConstantInSpecific` to a single caller in constant
evaluation, with a TODO to remove that.

This gets us closer to being able to fully perform type-checking against
abstract types instead of types anchored within a particular generic.
2025-04-02 22:52:11 +00:00
Richard Smith 8b9f1a8966 Don't re-evaluate imported constants. (#5217)
Trust that import_ref produces constants that are already in their
evaluated form. We still do one pass over the operands to map them into
their canonical constant values. Even that is mostly unnecessary, but
there are a few instructions produced by importing that still need it
for now.
2025-04-02 18:26:36 +00:00
Richard Smith 265968b396 Make evaluation of symbolic bindings simpler and more uniform (#5215)
Factor out logic to evaluate `EntityNameId` instead of duplicating it
between `BindSymbolicName` and `SymbolicBindingPattern`. Remove support
in `SymbolicBindingPattern` for evaluating a pattern to the constant
value of the corresponding binding, which doesn't really make any sense
given that patterns don't generally evaluate to the value that they
matched.

This results in the handling for `SymbolicBindingPattern` being simply
the default handling for an always-constant instruction, so remove the
special case for it entirely and change its constant kind to `Always`.
It's not entirely clear that it makes sense for `SymbolicBindingPattern`
to be treated as a constant when other patterns aren't, but we seem to
be relying on this in various places, so leave it as a constant for now.
Changing it to never be constant will be a smaller change now -- it just
requires changing the `constant_kind`.

The IR changes in the tests are fairly widespread, but mechanical, and
there are two kinds of things changing:

- `symbolic_binding_pattern`s in specifics now evaluate to
`symbolic_binding_pattern`s, not to the argument values. This means in a
few cases we end up with additional `symbolic_binding_pattern`
constants.
- We evaluate the type operand of `symbolic_binding_pattern` now, so an
error in the type will now properly be propagated into an error in the
pattern's constant value.
2025-04-01 20:24:00 +00:00
Jon Ross-Perkins 9134e36ec0 Extend CARBON_KIND_SWITCH to support ArgAndKind (#5216)
This builds on #5212 which is adding ArgAndKind. This further modifies
CARBON_KIND_SWITCH support so that we can use it with ArgAndKind in
addition to Inst. That creates a quirk where it's easier if ArgAndKind
provides `kind` as an accessor instead of a data member, so I'm just
switching it to a class.
2025-03-29 00:37:46 +00:00
Jon Ross-Perkins 4cb61ae4e1 Remove ArgKinds to encourage safer coding patterns (#5212)
#5171 ran into an issue where the wrong kind was associated with an arg
(`auto arg1 = RefineOperand(context, loc_id, arg0_kind,
action.arg1());`). This PR is trying to reduce risk of similar errors by
replaced `ArgKinds()` with instead an `ArgAndKind` structure and
corresponding accessors.

A couple things I considered and discarded were:

- Adding `CARBON_KIND_SWITCH` support (in this PR -- see #5216).
- The particular way that `ForCase` works would need to change, and I
was hesitant to do that here.
- But this is why I did add `As` to `ArgAndKind`, because it had me
thinking in that direction.
- Trying to make wrapper functions like `MutateArgs(callback_fn);`. This
kind of approach gets a little messy due to some of the conditional
passes, and in particular the reverse-iteration done for `PopOperand` in
subst.cpp
- Making something like `args_and_kinds() -> std::array<ArgAndKind, 2>`.
There's one spot where iteration is already set up as a loop, but for
others it felt a little convoluted with less gain than
`MutateArgs`-style things.

I'm not sure if there's a better way to set up the table generators, I
might keep tinkering with those for ideas.
2025-03-28 23:24:36 +00:00
Boaz Brickner 181c7b9290 Change EvalContext.context_ from reference to pointer (#5203)
Per [the style
guide](https://github.com/carbon-language/carbon-lang/blob/trunk/docs/project/cpp_style_guide.md#syntax-and-formatting):
* If it is captured and must outlive the call expression itself, use a
pointer and document that it must not be null (unless it is also
optional).
* When storing an object's address as a non-owned member, prefer storing
a pointer.
2025-03-28 14:48:18 +00:00
Jon Ross-Perkins 0a3efb76ed Use DiagnosticEmitter for phase-specific types (#5188)
Given the namespacing of `Diagnostics` in #5173, now we can use
`DiagnosticEmitter` for phase-specific emitters. This is consistent with
how we do `Context`, and also check had started this with
`DiagnosticBuilder` in anticipation of the namespacing.

Also renames `Emitter::DiagnosticBuilder` to `Emitter::Builder` for
consistency with other `Diagnostics` entities.

In check, I'm still splitting `DiagnosticEmitterBase` and
`DiagnosticEmitter` just to keep the emitter definition separate from
the context.

Also cleans up some incorrect check diagnostic emitter dependencies in
lower.
2025-03-27 00:41:30 +00:00
Richard Smith 4acc9cac5d Replace GetInstForSpecific with direct support for rendering a SpecificId in diagnostics. (#5192)
Avoids misbehavior caused by GetInstForSpecific's side effects, such as
recursively reentering constant evaluation.
2025-03-26 22:53:32 +00:00
Jon Ross-Perkins acbe6530c3 Move diagnostics into a namespace (#5173)
What this really does is avoids shadowing names, so that we can
comfortable have things like `Check::DiagnosticEmitter` or
`Check::DiagnosticLoc` without shadowing being a concern.

Note, down this path I'm also thinking about:

- Renaming misc DiagnosticConsumer/DiagnosticEmitter classes, possibly
just to DiagnosticConsumer/DiagnosticEmitter (so
`Check::DiagnosticEmitter` instead of `SemIRLocDiagnosticEmitter`).
- Dropping `Diagnostic` from `Emitter::DiagnosticBuilder`.
- But not for `Check::DiagnosticBuilder`, because `Check::Builder` would
be ambiguous.
- Renaming diagnostics/diagnostic_* to drop "diagnostic".

[Discussion about SemIRLoc ->
DiagnosticLoc](https://discord.com/channels/655572317891461132/655578254970716160/1353771570463768698)
reminded me of this (in particular the older [Check::DiagnosticBuilder
discussion](https://discord.com/channels/655572317891461132/655578254970716160/1344363562608627763)),
but I'd only do that rename if there's matching consensus about a path
forward where we keep SemIRLoc, and in a way that it's only ever used
for diagnostics (the divergence from which is at the root of current
LocId discussion).

I'm trying to keep that separate from a namespace addition for clarity.
2025-03-26 19:12:10 +00:00
Dana JansensandJon Ross-Perkins 53c98a8619 Support specialization in impl lookup with a symbolic query/impl. (#5169)
Add a new instruction called ImplSymbolicWitness which represents a
search for an impl declaration given a self type and an interface to
find implemented for the self type. The self type is stored as a
constant instruction id, rather than as a ConstantId, as instructions
don't currently support holding ConstantId. The interface is stored as a
SpecificInterface but we can't fit all of it directly into the
instruction. So we add a new id to refer to the SpecificInterface as
follows.

Add a new SpecificInterfaceId which indexes into a canonical value store
on SemIR::File. This tracks all `SpecificInterface`s stored in an
instruction - specifically the ImplSymbolicWitness instruction.

The SpecificInterface on Impl is still stored there as a value, not as
an id, and no id is eagerly constructed for it. We wait until an id is
needed to make one. Since they are canonical, a new id is only create
when a new SpecificInterface value is seen.

When doing impl lookup, and the query is not concrete, and the impl is
not effectively final, the query needs to consider future impls that may
specialize either the self type or the constaint to make a more precise
match and replace the found impl declaration. Instead of returning the
ImplWitness instruction from the found impl, we generate a
ImplSymbolicWitness instruction, storing the query so that it can be
replayed later. This instruction is added to the generic eval block and
thus will be re-evaluated later with a SpecificId that may make the
query more concrete. When evaluating the instruction and replaying the
query, the lookup has the same conditions and if it does not decide to
use the found impl concretely, then the same instruction is returned
from eval, leaving it as symbolic.

--- Impl lookup changes ---

Impl lookup gets a little more interesting now. It continues to look in
the facet value for a witness if the self type is a facet value. Then
falls back to looking for an impl declaration. This step is no longer
done directly. Instead, we construct a ImplSymbolicWitness instruction
and evaluate it immediately for each interface that are in the query
facet type.

The ImplSymbolicWitness instruction, when evaluated, calls back to the
impl lookup code, with a query specific interface. There we resume back
into the same code path as from before, finding a witness in an impl
declaration. But we may return "found a non-final impl" instead of a
concrete witness. If eval receives this back, it evaluates to the
current ImplSymbolicWitness instruction as the resulting constant value.

To pass lookup failures back through eval, a result of InstId::None from
the second step of impl lookup will result in a non-constant value,
which is used as a signal back up the stack to the original impl lookup
function that the lookup failed. Using a non-constant value here would
break evaluation of the generic eval block if impl lookup could fail
there, however we know it will not since we only leave behind an
ImplSymbolicWitness instruction in the eval block if we found at least
one matching impl already, and we just want to look for a better match
with a more specific query.

We must take care to not store a reference into any value store across
computation in impl lookup, since impl lookup can recurse into itself
invalidate those stores. That includes the SpecificInterface obtained
from a SpecificInterfaceId, which impl lookup also inserts into the
store.

--- The long tail ---

Adding a new instruction and a new id type requires a myriad of changes
to support them:

We add Dump() support for SpecificInterfaceId. And fix a crash in Dump
for SpecificId::None. We also add MakeSpecificInterfaceId() for dumping
arbitrary ids.

The type of ImplSymbolicWitness is a new singleton builtin type
instruction called WitnessSymbolicType (like WitnessType is the type for
an ImplWitness).

Both ImplSymbolicWitness and WitnessSymbolicType are given `Value` as
their expression category as they are builtin constant values. And
BuildInfo() in TypeCompleter is taught about them both, returning a
`ValueRepr::Copy`.

WitnessSymbolicType is added to the set of SingletonInstKinds, so that
it can have a singleton instrution id as a static member.

Lower's BuildTypeForInst() is taught to make an empty struct for
WitnessSymbolicType, similar to WitnessType.

Instruction formatter (FormatterImpl) grows support for printing a
SpecificInterfaceId so that it can print both arguments of
ImplSymbolicWitness on the RHS when printing the SemIR instruction. To
print a SpecificInterfaceId, it prints both the interface id and the
specific id (if there is one). For example, for a query on a generic
interface `Z` with one parameter, the RHS includes the query, interface,
and specific:
```
%Z.impl_symbolic_witness: <symbolic witness> = impl_symbolic_witness %U, @Z, @Z(%U.as_type) [symbolic]
```

IdKind is extended to include SpecificInterfaceId.

InstFingerprinter is taught to look through SpecificInterfaceId and use
the interface and specific ids in the fingerprint.

InstNamer is taught about SpecificInterfaceId, counting the interfaces
when building an index. It is also tought about ImplSymbolicWitness,
using the name of the interface within and the `.impl_symbolic_witness`
suffix. For example, here the LHS is named after the interface in the
query:
```
%Z.impl_symbolic_witness: <symbolic witness> = impl_symbolic_witness %U, @Z, @Z(%U.as_type) [symbolic]
```

StringifyTypeExpr is taught about WitnessSymbolicType, which uses its IR
name since it's a singleton. And about ImplSymbolicWitness which uses
its constant value. The handling of ImplWitnessAccess also needed to be
adjusted, since it assumed that ImplWitnessAccess::witness_id would
always be a FacetAccessWitness, but it can now also be an
ImplSymbolicWitness. (It seems that the witness_id is also assigned
ImplWitness instructions, but those ImplWitnessAccess instructions don't
ever seem to get stringified in a diagnostic at this time.) At the
moment the ImplWitnessAccess with a symbolic witness is just stringified
as "<symbolic>", such as in:
```
x.carbon:1:2: error: cannot implicitly convert value of type `()` to `<symbolic>` [ConversionFailure]
  let a: C(D).(Z.X) = ();
                      ^~
```

There is a TODO left behind to include more information there.

The TypeStructure builder is made to handle WitnessSymbolicType and
WitnessType. These come up now in deduce where a generic impl will have
a ImplSymbolicWitness in a FacetValue for a generic self type. The query
may have a concrete ImplWitness in the same position. Since deduce tries
to deduce through the FacetValue, it tries to convert ImplWitness to
ImplSymbolicWitness, tries to do an impl lookup for `impl ImplWitness as
ImplicitAs(ImplSymbolicWitness)` and causes us to build type structures
with each of these.

Subst is updated to handle pushing and popping SpecificInterfaceId.
Without this, when finishing a generic's eval block, we would walk into
the ImplSymbolicWitness instruction, and its arguments, and fail to
recurse down into the SpecificInterfaceId. Then any specifics inside
would be left as "orphaned" without any generic id attached to them, and
we would never update the instructions in the SpecificInterface's
instructions (inside its own SpecificId) with new constant values when
evaluating the generic eval block against a specific. To do this we push
the specific_id inside the SpecificInterface, and when popping we pop
the specific_id then construct a new canonical SpecificInterface with it
and return that id.

We add support for importing ImplSymbolicWitness by importing its self
constant instruction and specific interface id. However we also had to
add import support for SpecificImplFunction, which can now appear in the
generic eval block for a generic impl declaration, and thus must be
imported with the declaration. This is done very similarly to
SpecificFunction, except the `type_id` is a singleton value.

---------

Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
2025-03-26 15:10:23 +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
Dana Jansensandjosh11b 5724407e4d Delete the GetConstantValue overload for AbsoluteInstId (#5145)
This prevents conversion from an InstId which is its base class, and
documents that this is invalid in the code.

Also expand the comment on the AbsoluteInstBlockId, which I had locally
but seem to have not saved and included in #5141.

---------

Co-authored-by: josh11b <15258583+josh11b@users.noreply.github.com>
2025-03-19 03:59:04 +00:00
Dana Jansens a801a982bc Delete the GetConstantValue overload for AbsoluteInstBlockId (#5141)
This prevents conversion from an InstBlockId which is its base class,
and documents that this is invalid in the code.
2025-03-18 16:29:28 +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
Richard Smith f30fa2d3db Move the EvalConstantInst overloads out of eval.cpp into their own file. (#5040)
For now they're all in the same file; we might consider splitting them
further if that file gets too large.
2025-02-28 00:50:43 +00:00
Dana JansensandJon Ross-Perkins 129cf35d78 Support BitAnd operator between facet types (#5022)
Doing so results in TODOs in the resulting semir, since we don't handle
combining the facet types together properly or doing lookup into them.
There's a test added demonstrating this, which will be made to work in
followups.

---------

Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
2025-02-27 17:53:48 +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
Jon Ross-Perkins 422cc3d48a Move diagnostic usings off Context (#5007)
There aren't remaining uses on `Context` other than `DiagnosticEmitter`
itself. I'm adding `SemIRLoc` because I feel odd about having both
`Carbon::Check::DiagnosticBuilder` and
`Carbon::DiagnosticEmitter<T>::DiagnosticBuilder`, but it seems
relatively little additional typing outside the handful of
`DiagnosticEmitter` uses on `Context` itself:

```
Context::DiagnosticEmitter
DiagnosticEmitter<SemIRLoc>

Context::DiagnosticBuilder
SemIRLocDiagnosticBuilder

Context::BuildDiagnosticFn
BuildSemIRLocDiagnosticFn
```

Also clean up #include's while I'm finishing here.
2025-02-26 18:44:36 +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
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
Jon Ross-Perkins dc8f47e6ad Move type functions off Context (#4951)
This creates a new check/type.h for most logic, and also moves some
functions to TypeStore in sem_ir/type.h. My approach for TypeStore is to
focus on moving the read-only functions there.
2025-02-13 23:02:38 +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 3f599c250b Generate Cpp namespace when import Cpp is used (#4873)
Also defined a dedicated `ImportCppDecl` `InstKind`.
Part of #4666
2025-02-12 01:44:37 +00:00
Jon Ross-Perkins 0a55081c5d Move TypeCompleter and closely related helper functions to their own file (#4922)
context.cpp is getting large, so I'm looking at a few ways to cut out
clusters of functions. This felt like a logical cluster of functions to
move to their own file.

Note I have two commits in this PR: one moving the functionality to a
new file, and one specifically changing TypeCompleter to use out-of-line
function implementations. This is to assist reviewability.
2025-02-11 18:51:46 +00:00