Commit Graph
9 Commits
Author SHA1 Message Date
Nicholas Bishop 5e62791ad2 Improve ClangDeclStore ergonomics (#7311)
Change `Lookup` by InstId to return a ClangDecl pointer. All callers
were immediately calling `Get` anyway, so this makes call sites a little
shorter. The other `Lookup` method, by ClangDeclKey, is sometimes called
without calling `Get`, so left that as-is, but renamed to `LookupId`.

Also add a `decl` method to ClangDecl so that the commonly repeated
`clang_decl->key.decl` can be written `clang_decl->decl()`.
2026-06-05 20:49:34 +00:00
Nicholas BishopandRichard Smith 1aa34d7642 Remove CppGlobalVarStore (#7309)
Replace all uses of CppGlobalVarStore store with ClangDeclStore.

Adding a VarStorage->VarDecl mapping to ClangDeclStore is now done with
the `AddVar` method, which takes an extra `pattern_id` arg. While the
corresponding `ClangDecl` is unchanged from before, the reverse mapping
in `inst_id_to_clang_decl_id_` now uses the `pattern_id` as the key.
This is necessary because in some places the original VarStorage
instructions gets replaced (e.g. by a call to `Convert`). The
`pattern_id` remains stable in those cases.

---------

Co-authored-by: Richard Smith <richard@metafoo.co.uk>
2026-06-05 02:07:46 +00:00
David Blaikie 2d87bb02d9 Use clang_decls as the source of truth for function interop mapping (#7303)
Removing the clang_decl_id on SemIR::Function - using only the
clang_decls map to create the association between SemIR::Function and
clang::FunctionDecls.

This adds an `is_external` flag to ClangDecl to indicate whether the
entity originated from Carbon or was imported from another language.
(I'm open to names - I guess for now we mostly use "is this from C++" to
be more specific than "is this external" - eg: NameScope::is_cpp_scope)
2026-06-04 23:16:11 +00:00
Richard Smith 49e5e15138 Fix mangling collisions for library-private entities. (#7283)
Include the library name in the fingerprint of an entity declared
`private` at namespace scope. Include the entity's fingerprint in the
mangling of a library-private entity.

This fixes miscompiles if two libraries in the same package declare
`private` entites with the same name. We can't fix this with internal
linkage because library-private entities can be reachable through
generics defined in the API file of the library.

Assisted-by: Gemini via Antigravity
2026-06-01 19:19:08 +00:00
Richard Smith be70c092fa Add a text mode for fingerprinting. (#7231)
The intent is to add visibility into how the fingerprint is computed, so
that fingerprinting issues and mangling collisions can be more readily
understood and fixed.

Assisted-by: Gemini via Antigravity
2026-05-19 23:16:51 +00:00
Dana Jansens 8e371c380a Use impl's interface to get the specific interface from the identified facet type (#7201)
Instead of doing a lookup for the identified facet type from the impl's
self+constraint, we can use `impl.interface` to get the specific
interface being implemented by the impl declaration. This is already the
specific interface returned from the identified facet type. And that
means we no longer have to identify the self+constraint for imported
impls.

This is split out from
https://github.com/carbon-language/carbon-lang/pull/7183#discussion_r3230571153
2026-05-14 19:34:23 +00:00
Richard Smith bc06f6c5ec Mangle the signature decl when mangling a thunk. (#7177)
Fixes mangling collisions when two thunks with the same name (eg, `Op`)
are created in the same context, which in turn would lead to LLVM
verifier failures and miscompiles.

To support this, add a new value store to track a little more
information about thunks beyond what's in the `Function`.
2026-05-07 21:58:29 +00:00
Nicholas Bishop 0075d530b9 Support const eval when calling a C++ thunk (#6947)
This makes it possible to do const eval when calling a constexpr C++
function with params and return types other than 32/64-bit integers.

Most of the new logic is in `MaybeModifyCppThunkCallForConstEval`, which
is called by `MakeConstantForCall`. This checks if the callee is a C++
thunk (using a new `SpecialFunctionKind::CppThunk` variant), and if so
it:
* Changes the callee from the C++ thunk to the thunk's callee
* Remaps parameters that are passed by pointer to the thunk to the
underlying value
* Drops the return value parameter, if present
2026-04-01 21:34:41 +00:00
Nicholas Bishop 1ef35e8299 Fix name mangling for Carbon functions called from C++ (#6984)
Since this requires using the `Mangler` class from `toolchain/check`,
moved it from `toolchain/lower` to `toolchain/sem_ir`.

The mangled name is then attached to the `FunctionDecl` with an
`AsmLabelAttr`.
2026-03-27 22:52:11 +00:00