summaryrefslogtreecommitdiffstats
path: root/source/slang/slang-check-type.cpp
Commit message (Collapse)AuthorAge
* Split overloaded uses of RefType in front-end (#8427)Theresa Foley2025-09-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Overview ======== This change is the start of an attempt to address how the Slang compiler codebase has ended up conflating two similar, but semantically distinct, concepts: * The long-standing notion of `ref` parameters (only allowed for use in the builtin modules), which are encoded using a wrapper `Type` in the AST as part of the representation of the parameters of a `FuncType`. * A recently-introduced notion of explicit reference types that mirror the built-in `Ptr` type, with a relationship comparable to that between pointer and reference types in C++. The change splits the `Ref<T>` type in the core module into two distinct types, with one for each of the two use cases. Similarly, the `RefType` class in the compiler's AST is split into two distinct classes, to represent the two cases. Background ========== The `Ref<T>` type in the core module (hidden and not intended for users to ever see or use) was originally introduced to encode the `ref` parameter-passing mode, comparable to the hidden `Out<T>` and `InOut<T>` types used to encode `out` and `inout` parameter-passing modes. The `Ref<T>` type in the core module was encoded as a instance of the `RefType` class in the Slang AST (similar to how `Out<T>` mapped to an `OutType`). These AST classes were *only* intended to be used by the compiler front-end as part of its encoding of function types. The `FuncType` class needed a way to distinguish an `inout int` parameter from a plain (implicitly `in`) `int` parameter, so these wrapper like `RefType` and `OutType` were introduced to encode both the parameter type (`T`) and the parameter-passing mode in a form that could be passed around as a `Type`. Notably, the `Ref<T>` type (and `Out<T>`, etc.) were *not* intended to be type names that ever get uttered in Slang code (not even in the builtin modules), and the vast majority of the compiler code was not supposed to ever encounter them. They were an implementation detail of `FuncType`, and nothing else. (In hindsight it may have been a mistake to use a nominal type declared in the core module to implement these wrappers; it might have been a good idea to use an entirely separate class of `Type` for this case...) Recent changes to the builtin modules introduced functions that wanted to *return* a reference (so that the parameter-passing-mode modifiers like `ref` could not trivially be used), and as part of those changes the appealingly-named `Ref<T>` type in the core module was re-used for this new case. Builtin operations were declared with an explicit `Ref<T>` return type, and parts of the compiler front-end that had previously been blissfully unaware of the AST's `RefType` (and `InOutType`, etc.) had to start accounting for the possibility that an explicit `Ref<T>` would show up. Related changes also introduced a comparable conflation of the (unfortunately-named) `constref` parameter-passing modifier and builtin operations that wanted to return an explicit reference that is read-only. Both use cases were mapped to the core-module `ConstRef<T>` type, which appeared in the AST as an instance of the `ConstRefType` class. The overlapping use of `ConstRef<T>`` is actually significantly more troublesome than the `Ref<T>` case because, despite what its name implies, `constref` was not really supposed to be the read-only analogue of `ref`, but rather it is closer to the "immutable value borrow" analogue to `inout`'s "mutable value borrow." The semantics of a "value borrow" vs. a "memory reference" in Slang have not been very carefully codified, and the conflation around `ConstRef<T>` has contributed to things becoming increasingly muddy in the compiler back-end. Main Changes ============ Core Module ----------- The `Ref<T>` type has been replaced with two distinct types, with one for each use case: * `RefParam<T>` is intended for use when encoding a `ref` parameter in a function type * `ExplicitRef<T>` is intended for use when an operation in a builtin module wants to return a reference The other types used to represent parameter-passing modes (e.g., `InOut<T>`) were renamed to better indicate that their role in defining parameter types (e.g., `InOutParam<T>`). The `ExplicitRef<T>` type was given additional generic parameters for the allowed access and the address space, akin to what `Ptr<T>` now supports. The pointer dereference operator (prefix `*`) in the core module should now properly propagate the access and address space of the pointer over to the reference that gets returned. The two distinct use cases of `ConstRef<T>` were not split in the way as `Ref<T>`, instead the case for the `constref` parameter-passing mode uses `ConstParamRef<T>`, while cases that previously used `ConstRef<T>` to represent a read-only explicit reference instead now use `ExplicitRef<T, Access.Read>`. Prior to this change there were two subscripts declared on pointers: one in the `Ptr` type itself, and another in an `extension` for pointers with `Access.ReadWrite`. The comments on the code seemed to indicate that the catch-all subscript used to only have a `get` accessor, while the `ref` was only available on read-write pointers, but it seems that subsequent changes converted the default subscript to support `ref`. This change eliminates the subscript added via `extension`, since it is redundant. AST and Front-End ================= Similar to the changes in the core module, the AST `RefType` class was split into: * `RefParamType` for the case of encoding `ref` parameters * `ExplicitRefType` for the case where the user meant an explicit reference type All the other classes that represent wrappers for encoding parameter-passing modes (e.g., `OutType`) were similarly renamed (e.g., `OutParamType`). The `ConstRefType` class was simply renamed to `ConstRefParamType`, because any use cases of `ConstRefType` that intended an explicit reference type will now use `ExplicitRefType` with `Acccess.Read`. For convenience, this change includes type aliases to map the old names for these types over to the new ones (e.g., `using OutType = OutParamType`) so that the change doesn't need to affect quite so many lines of code. The `RefType` and `ConstRefType` names are intentionally left undefined, since it woudl be unsafe to assume that existing use sites should default to either of the two possible interpretations. All use cases of `RefType` and `ConstRefType` (and their former shared base class `RefTypeBase`) were audited and updated to refer to either `RefParamType`/`ConstRefParamType` or `ExplicitRefType`, as appropriate (based on whether the context of the code indicated it was working with parameter-passing mode wrapper types, or explicit reference types). In many (many) cases comments were added to the code that was updated (and some unrelated code that needed to be audited along the way) to note cases where there appears to be something fishy going on in the compiler and/or there are obvious opportunities for next-step improvement. The `QualType` constructor used to infer l-value-ness when passed a `RefType` or `ConstRefType`; that code was introduced to support explicit reference types. The code was updated to consult the access argument of an `ExplicitRefType` to try and determine the right l-value-ness to use. There is some ambiguity about what should be done in the case where the value of the generic argument representing the access cannot be statically determined; a better solution may be needed. Many other cases in the front-end that were working with `RefType` and `ConstRefType` for explicit references also need to figure out l-value-ness, and these were changed to rely on the logic already added to `QualType` so that it wouldn't have to be duplicated. It isn't clear if this structure is the best way to tackle the problem, but it seems to at least be an upgrade over the more strictly ad-hoc logic that was in place before. Future Work =========== IR-Level Work ------------- The most obvious next step to take is that the split that was made in the compiler front-end needs to be properly plumbed through all of the back-end. There appears to be a lot of code in the back end of the compiler that has made the same conflation of `ref` parameters and explicit reference types that the front-end did. In practice, any uses of `ExplicitRef<T>` in the front-end should desugar into plain pointer-based code in the IR. Clean Up Parameter-Passing Modes -------------------------------- The code that handles different parameter-passing modes (`ParameterDirection`s) and their wrapper types is somewhat scattered and messy (as found while auditing use cases of `RefType`). A cleanup pass is warranted to ensure that most code only needs to think about `ParameterDirection`s. There should ideally be only a single operation in the front-end that handles determining the `ParameterDirection` of a parameter based on its modifiers. Similarly, there should be one operation to wrap a value type based on a parameter direction, and one operation to derive a `ParameterDirection` from the wrapper type. Ideally, the accessors for `FuncType` should not provide unrestricted access to the potentially-wrapped parameter types, and should instead return some kind of `ParamInfo` struct that encodes both a `ParameterDirection` and the unwrapped `Type` of the parameter. Clean Up `QualType` ------------------- A significant piece of future work that appears required is to drastically clean up and improve the way that `QualType`s are represente and handled in the front-end. There are currently various distinct `bool` flags in `QualType` (some with very unclear meaning) and differnet parts of the codebase consult/modify only subsets of them; a clear enumeration of the "value categories" (to use the C++ terminology) that Slang supports could be quite helpful. Naively, a `QualType` should at least encode the basic information that a `Ptr` type encodes: * A value type * Allowed access (read-only, read-write, etc.) * Address space The main additional thing that a `QualType` needs is a way to distinguish cases where an expression evaluates to: * A reference to a memory location, where all the information from a `Ptr` is relevant * A simple value, such that the access and address space are irrelevant * A reference to an abstract storage location (a `property`, `subscript`, or an implicit conversion that needs to support being an l-value), in which case address space is irrelevant and the "allowed access" basically amounts to a listing of the accessors the storage location supports Eliminate Explicit Reference Types ---------------------------------- Finally, twe should eventually eliminate the `ExplicitRef<T>` type from the core module (and all of the supporting code from the front-end), since the feature is not a good fit for the Slang language. We should find some other way to decorate operations in the builtin module that need to returns a reference rather than a value (note how `ref` accessors already avoided exposing explicit reference types, by design). --------- Co-authored-by: slangbot <186143334+slangbot@users.noreply.github.com>
* Fix Conditioanl<T, false> fields with a semantic. (#7855)Yong He2025-07-22
| | | | | | | * Fix Conditioanl<T, false> fields with a semantic. * Add unit test. * Fix test.
* Mediate access to ContainerDecl members (#7242)Theresa Foley2025-06-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Most of what this change does is straightforward: take all the places in the code that used to operate directly on `ContainerDecl::members` and related fields, and instead have them call into a smaller set of accessor methods defined on `ContainerDecl`. The primary motivation for making this change is that in order to implement on-demand loading of members from serialized AST modules, we need a way to identify and intercept the "demand" for those members. On-demand loading benefits from having all accesses to the members of a `ContainerDecl` be as narrow as possible. If a part of the code only need a member at a specific index, it should say so. If it only needs access to members with a specific name, or a given subclass of `Decl`, then it should say so. A secondary motivation for this change is that there have recently been several changes that added complexity and special cases by introducing code that operated on (and *mutated*) the member list of a container decl in ways that the existing code had never done before. Any code that mutates the member list of a `ContainerDecl` needs to be sure to not disrupt the invariants that the lookup acceleration structures currently rely on. One of the recent changes added a declaration-to-index map to the set of acceleration structures (with different validation/invalidation behavior than the others...) while other recent changes would remove or insert declarations in ways that could change the indices of other declarations in the same container. It is not clear if any of these pieces of code were aware of the others, and the invariants that might be expected or broken along the way. This change bottlenecks the vast majority of accesses to the members of a `ContainerDecl` through the following operations: * Getting a `List` of all of the direct member declarations of a container * Get the number of direct member declarations, and accessing them by index. * Looking up the list of direct member declarations with a given name. * Adding a new direct member declaration to the end of the list. Some other operations are layered on top of those (e.g., getting a list of all the direct member declarations of a given C++ class). These layered operations are still centralized on the `ContainerDecl`, with the intention that we *can* change them to be non-layered implementations if we ever need to for performance (e.g., by building a lookup structure for finding member declarations by their type). The exceptional cases of access/mutation on the direct members of a `ContainerDecl` have also been encapsulated, but rather than expose what would risk appearing like general-purpose accessors (e.g., `removeDecl(d)`, `setDecl(index)`, etc.), these operations have been explicitly named after the specific use case that they serve in the codebase today, to discourage others from using them for more kinds of operations we'd rather not support. These operations have also been given parameter signatures that match their use cases, to make it so that even somebody determined to abuse them would have to invent suitable arguments out of thin air. In the case of the declaration-to-index mapping, this change eliminates that acceleration structure, in favor or slightly more complicated (and possibly inefficient, yes) code at the use site. Over time, it would be good to closely scrutinize each of the use cases that requires more complicated interaction with the members of a `ContainerDecl`, to see whether any of them can be reframed in terms of the more basic operations, or if there is some clean abstraction we can introduce to make operations that mutate the member list feel like... hacky.
* Add checking for hlsl register semantic. (#7118)Yong He2025-05-15
| | | | | | | | | | | * Add checking for hlsl register semantic. * Fix. * Fix test. * Fix switch error. * Fix tests.
* Implement spec const for generic parameter (#7121)kaizhangNV2025-05-15
| | | | | | | | | | | | | | | | | | Close #6840. This PR add supports to use specialize constant in generic parameter, and that parameter can also be used as array size, e.g. following code should work: ``` struct MyStruct<let N: int> { float buffer[N]; } MyStruct<SpecConstVar> s; ``` - Loose the restriction from Link-Time to SpecializationConstant when extract generic argument - Tweak the logic of how we decide whether a inst is hoistable. Besides checking existing hoistable flag of each IRInst, when we detect a IRInst's type is SpecConstRateType, we will treat that inst hoistable. Because IRInst in global scope can be deduplicated, and every SpecConstRateType inst should be in the global scope or IRGeneric scope (which will be at global scope after specialization). - Remove the SpecConstIntVal to IRInst map in IR lowering logic, because we already have way to deduplicate the global scope IR.
* support specialization constant sized array (#6871)kaizhangNV2025-05-14
| | | | | | | | | | | | | | | | | | | | | Close #6859 Goal of this PR We want to support an array whose size can be specialization constant for shared/global variable e.g. layout (constant_id = 0) const uint BLOCK_SIZE = 64; shared float buf_a[(BLOCK_SIZE + 5) * 4]; Overview of the solution: During IndexExpr check, we will loose the restriction to allow SpecConst passing, but the size parameter will not be a constant value because it cannot be folded into a constant, so we will make it follow the same logic as generic parameter value, and the size will be represented by FuncCallIntVal/PolynomialIntVal/DeclRefIntVal. During IR lowering, we will detect whether there is spec constant in the IntVal, and wrap the IRInst with a SpecConstRateType, and propagate the type though the lowering logic, such that the IntVal representing the array size will have SpecConstRateType. During spirv emit stage, if we detect that a IRInst has SpecConstRateType, we will emit it as SpecConstantOp. We have to implement new logic to emit OpSpecConstantOp, the existing emit logic doesn't support emitting OpSpecConstantOp, especially this op can embed arithmetic operation at global scope, where we can only emit arithmetic instruct at local. But there are only few instructs we need to support. Overview of the solution: This PR doesn't support generic, and we will create a separate PR to extend that, tracked in #6840.
* A new approach to AST serialization (#6854)Theresa Foley2025-04-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * A new approach to AST serialization This change completely overhauls the way that AST nodes are being serialized, and the offline source-code generation steps that enable that serialization. In practice, this ends up being a complete overhaul of the way that *modules* are being serialized (not just the AST part), although things like the serialization format for the Slang IR and for source locations are not affected. The rest of this commit message is broken down in to sections, in an attempt to help guide anybody looking at the code in how to make sense of all the changes. The Old C++ Extractor --------------------- AST serialization used to be driven by information scraped using the `slang-cpp-extractor` tool, which did an ad hoc parse of the C++ declarations of the AST node types and then generated a set of "X macros" that could be for macro-based code generation within the rest of the compiler. While the existing approach was functional, it wasn't easy to understand or maintain, and it has been getting in the way of forward progress on other features we'd like to work on in the language and compiler. This change removes the `slang-cpp-extractor` tool entirely. Marking Up the AST Declarations ------------------------------- The most notable change that contributors to the compiler may notice is the large number of invocations of a macro `FIDDLE()` on the declarations of the AST node types. The basic idea is that only declarations (namespaces, types, fields) that are preceded by `FIDDLE()` are visible to the code generator tool. So if somebody is working with the AST and wondering why a new node type isn't working, or why a field they added isn't being serialized correctly, it is probably because they need to add `FIDDLE()` in front of it. Generating the Boilerplate Code ------------------------------- The file `slang-ast-boilerplate.cpp` provides a good example of how the information extracted from the marked-up AST declarations gets used. In that file, the `FIDDLE TEMPLATE` construct is used to generate type information for each of the AST node types. Similar logic is used in `slang-ast-forward-declarations.h` to generate the declaration of the `ASTNodeType` enumeration, and forward-declare all the AST node classes. For many parts of the code, simply including that file replaces the need for the old `slang-generated-*.h` files. Replacing Visitors and Related Logic ------------------------------------ The old visitor types for the AST used the macros that were generated by `slang-cpp-extractor`, so something new was needed to replace them. The same goes for the `SLANG_AST_NODE_VIRTUAL_CALL` macros. The core of the solution implemented here is in `slang-ast-dispatch.h`. Given a "dispatchable" AST node type (say, `Expr`), a call like: ``` ASTNodeDispatcher<Expr,R>(expr, [&](auto e) { return doSomething(e); }) ``` is an expression of type `R`, which does the equivalent of something like: ``` switch(expr->getTag()) { case ASTNodeType::VarExpr: return doSomething(static_cast<VarExpr*>(expr)); // ... } ``` The `SLANG_AST_NODE_VIRTUAL_CALL` macro is now implemented in terms of `ASTNodeDispatcher`. The implementation of the visitor types is more involved. The code in this change retains some of the macro names from the original version, just to try and make the parallels more clear. The visitor types are all implemented on top of the `ASTNodeDispatcher` approach, and use `FIDDLE TEMPLATE` to generate all the boilerplate `visit*()` method declarations. Refactoring of `Linkage` Module Loading --------------------------------------- Needing to revisit all the places where modules get deserialized made it clear that there is a lot of complexity and apparent duplication in the core routines on the `Linkage` that get used for loading modules. This change tries to clean up some of that logic, but it is worth noting that there are two legacy features that get in the way of making things as clean as they should be: * The `LoadedModuleDictionary` type that gets passed around a lot exists entirely to handle the corner case where somebody uses the Slang API to perform a compilation with multiple `TranslationUnitRequest`s in the same `FrontEndCompileRequest`, and one of the translation units `import`s the module defined by another of the translation units. * There are a lot of special-case behaviors and routines entirely there to support the `ModuleLibrary` feature, although that feature should be considered deprecated (or at least subject to getting entirely re-designed down the line). The basic idea of the cleanup is that all of the (non-deprecated) ways load a module from a serialized binary, or compile one from source should now bottleneck through `loadModuleImpl`, which then bifurcates into `loadSourceModuleImpl` for the compilation case and `loadBinaryModuleImpl` for the deserialization case. High-Level Serialization Approach --------------------------------- The old serialization logic used the [RIFF](https://en.wikipedia.org/wiki/Resource_Interchange_File_Format) format to encode the high-level structure of things, and this change retains that usage (and actually doubles down on the RIFF usage). The old serialization system relied on the idea that for any given type `Foo` that wants to support serialization, there should be something like a `SerialFooData` type in C++, that can represent the state of a `Foo`, and then the actual serialization applied to that `SerialFooData`. This means that in most cases there are four pieces of code written: * During serialization: * Copying the data of a `Foo` in memory over to a `SerialFooData` in memory * Writing the state of a `SerialFooData` into the serialized data stream * During deserialization: * Reading the state of a `SerialFooData` from a serialized data stream * Copying the data of the `SerialFooData` in memory over to a `Foo` The new logic gets rid of the intermediate `SerialFooData`. In the serialization direction, we take a `Foo` and write it to the `RIFFContainer` directly, or using some other utilities layered on top of it. In the deserialization direction, we have additional flexibility. Given a `RIFFContainer::Chunk*` that represents a serialized `Foo`, we often navigate through the in-memory representation of the RIFF data to get to the parts of the serialized value that we actually want/need, without needing to deserialize the entire `Foo`. To support this kind of operation, this change introduces a few helper types like `ContainerChunkRef` an `ModuleChunkRef`, that are little more than typed wrappers around a `RIFFContainer::Chunk*`. The Module "Container" Part --------------------------- A serialized `Module` is encoded as a RIFF chunk, using logic in `slang-serialize-container.cpp` - both before and after this change. This change reorganizes a lot of the code in that file, to account for the way that eliminating the intermediate `SerialContainerData` type streamlines the overall task of writing out the parts of the module. In the deserialization logic... there isn't really much to do in `slang-serialize-container.cpp`. Most of the logic in `slang.cpp` and `slang-module-library.cpp` that pertains to deserializing modules uses the `ModuleChunkRef`-based approach, and simply extracts the pieces of the serialized module that it needs. The Actual Serialization of the AST ----------------------------------- The actual AST serialization logic is in `slang-serialize-ast.cpp`. The basic approach in both the writing and reading directions is: * Use the `FIDDLE TEMPLATE` system to generate a set of functions, one for each AST node type, that recursively invoke the read/write logic on each field of that node (after recursively invoking the case for its direct superclass) * Use the `ASTNodeDispatcher` system to dispatch out to those functions whene reading or writing anything derived from `NodeBase` * For now, handle all types *not* derived from `NodeBase` by hand. There's a lot of room for improvement around that last item: it should be just as easy to generate the serialization and deserialization logic for other types that don't inherit from `NodeBase`, but the current change tries to err on the side of making the logic as explicit and simplistic as possible, rather than trying to get too clever too soon. The actual serialization *format* used for the AST is almost comically simplistic: the code uses hierarchical RIFF chunks to emulate a JSON-like structure. This is a very wasteful representation (e.g., a `bool` or a null pointer each take up *8 bytes*), but the goal for now is to start with the simplest thing that could possibly work, and only add more cleverness once we are sure it won't get in the way of important future improvements (like lazy/on-demand deserialization or IR and AST, to improve compiler startup times). The files `slang-serialize.{h,cpp}` have been co-opted to define a new pair of types `Encoder` and `Decoder` that are used for a more-or-less stream-oriented way or reading or writing RIFF chunks for the JSON-like structure. Almost everything related to the actual AST serialization could do with a cleanup pass, and some time spent on picking good/better names for everything. Smaller Stuff ------------- * Cleaned up a lot of code that was using bare `ASTNodeType` or the extractor's `ReflectClassInfo` type to consistently use `SyntaxClass`. * Fixed an apparent bug in how the destination-driven code genarator was handling `TryExpr`s * Fixed an apparent bug in how the GLSL legalization pass was handling translation of certain `SV_*` semantics. * format code * fixup: template errors caught by non-VS compilers * format code * fixup: more template errors * fixup: more stuff VS didn't catch * fixup: it's amazing VS doesn't catch these... * fixup: yet more template stuff VS ignores * fixup: more VS template nonsense * fixup: unreachable return macro usage * fixup: more unreacable returns * fixup: unused parameter * fixup: strict aliasing * fixup: allow missing entry point list chunk * fixup: wasm build script * fixup: AST changes since this PR was created --------- Co-authored-by: slangbot <186143334+slangbot@users.noreply.github.com> Co-authored-by: Yong He <yonghe@outlook.com>
* Allow pointers to existential values. (#5793)Yong He2024-12-09
| | | | | | | | | | | | | | | | | | | * Fix pointer offset logic and add executable tests. * Fix. * Fix test. * Add existential ptr test. * Allow pointers to existential values. * Fix. * Fix. --------- Co-authored-by: Ellie Hermaszewska <ellieh@nvidia.com>
* Add datalayout for constant buffers. (#5608)Yong He2024-11-21
| | | | | | | | | | | | | | | | | | | * Add datalayout for constant buffers. * Fixes. * Fix test. * Fix glsl codegen. * Update spirv-specific doc. * Fix test. * Fix binding in the presense of specialization constants. * address comments. * Add a test for constant buffer layout.
* formatEllie Hermaszewska2024-10-29
| | | | | | | * format * Minor test fixes * enable checking cpp format in ci
* Variadic Generics Part 1: parsing and type checking. (#4833)Yong He2024-08-14
|
* Fix `sessionDesc.defaultMatrixLayoutMode` being ineffective. (#3753)Yong He2024-03-12
| | | | | | | | | | | | | | | | | | | * Fix `sessionDesc.defaultMatrixLayoutMode` being ineffective. * Fix matrix layout in buffer pointer. * Attempt to fix. * Fix buffer element type lowering for buffer pointers. * Add comment. * Fix test. * Fix member lookup in `Ref<T>`. * Fix validation error. * Enhance test.
* Link-time constant and linkage API improvements. (#3708)Yong He2024-03-07
| | | | | | | | | | | | | * Link-time constant and linkage API improvements. * Fix. * Allow module name to be empty. * Fix. * Fix. * Fix compile error.
* Parameter binding and gfx fixes. (#3302)Yong He2023-11-01
| | | | | | | | | | | * Parameter binding and gfx fixes. * Add diagnostics on entry point parameters. * Fix. --------- Co-authored-by: Yong He <yhe@nvidia.com>
* Added `[AutoPyBindCUDA]` for automatic kernel binding + `[PyExport]` for ↵Sai Praveen Bangaru2023-09-19
| | | | | | | | | | | | | | | | | | | | | | | exporting type information (#3209) * Initial: add a DiffTensor impl * Auto-binding and diff tensor implementations now work * Refactored diff-tensor implementation + added py-export for struct types * Cleanup * Update slang-ir-pytorch-cpp-binding.cpp * Updated test names * Update autodiff-data-flow.slang.expected * Add more versions of load/store & default generic args for DiffTensorView. * Add diagnostic for default generic arg and more tests * Add more `[AutoPyBind]` tests
* Redesign `DeclRef` and systematic `Val` deduplication (#3049)Yong He2023-08-04
| | | | | | | | | | | | | | | | | | | | | | | * Redesign DeclRef + Deduplicate Val. * Update project files * Fix warning. * Fix. * Fix. * Remove `Val::_equalsImplOverride`. * Rmove `Val::_getHashCodeOverride`. * Remove `semanticVisitor` param from `resolve`. * Cleanups. --------- Co-authored-by: Yong He <yhe@nvidia.com>
* Add `sampleCount` parameter for MS textures. (#3001)Yong He2023-07-19
| | | | | | | | | * Add `sampleCount` parameter for MS textures. * Fix test. --------- Co-authored-by: Yong He <yhe@nvidia.com>
* Simplify Lookup and improve compiler performance. (#2996)Yong He2023-07-18
| | | | | | | | | | | | | | | | | | | | | | | | | * Simplify lookup. * Various bug fixes. * Report type dictionary size in perf benchmark. * Remove type duplication. * increase initial dict size. * Bug fix. * Fix bugs. * Fixup. * Revert type legalization looping. * Fix specialization pass. --------- Co-authored-by: Yong He <yhe@nvidia.com>
* Make DeclRefBase a Val, and DeclRef<T> a helper class. (#2967)Yong He2023-07-07
| | | | | | | | | | | | | | | | | | | | | * Make DeclRefBase a Val, and DeclRef<T> a helper class. * Fixes. * Workaround gcc parser issue. * Revert NodeOperand change. * Fix. * Fix clang incomplete class complains. * Fix code review. * Small cleanups and improvements. --------- Co-authored-by: Yong He <yhe@nvidia.com>
* Fix most of the disabled warnings on gcc/clang (#2839)Ellie Hermaszewska2023-04-26
|
* Fixed crash when lowering IR for no_diff struct member. (#2658)Yong He2023-02-17
| | | | | | | | | * Fixed crash when lowering IR for no_diff struct member. * Improve `setInsertBeforeOrdinaryInst` and `setInsertAfterOrdinaryInst`. --------- Co-authored-by: Yong He <yhe@nvidia.com>
* Rework differential conformance dictionary checking. (#2483)Yong He2022-11-02
| | | | | | | * Rework differential conformance dictionary checking. * Revert space changes. Co-authored-by: Yong He <yhe@nvidia.com>
* Rename `JVPDerivativeModifier` -> `ForwardDifferentiableAttribute`. (#2472)Yong He2022-10-27
| | | Co-authored-by: Yong He <yhe@nvidia.com>
* Modified the new type system to support generic differentiable types … (#2413)Sai Praveen Bangaru2022-10-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | * Modified the new type system to support generic differentiable types and added support for differentiating overloaded functions. * Changed a few asserts to release asserts to avoid unreferenced variable errors * Fixed a naming issue with TypeWitnessBreadcumb::Flavor::Decl * Added logic to avoid tracking differentiable types if the module does not use auto-diff or define differentiable types. * Moved the auto-diff passes to after the specialization step, added a more complex generics test * Added a generics stress test and fixed AST-side logic. IR side needs some more work * Added differential getter and setter logic, fixed multiple issues with DifferentiableTypeDictionary, added support for loops and conditions * Changed differential getters to use pointer types, added getter type checking * Fixed some bugs related to diff type registration and differential getters * Removed some superfluous code * Removed some more unused code. * Fixed an issue with witness substitution * Minor fix Co-authored-by: Yong He <yonghe@outlook.com>
* Deduplicate AST type nodes and cache lookup operations. (#2397)Yong He2022-09-13
| | | | | | | | | | | * wip: dedup AST type nodes and cache lookup. * Fix. * Remove profiling. * Fixes. Co-authored-by: Yong He <yhe@nvidia.com>
* Make Optional<PointerType> lower to PointerType instead of a struct. (#2373)Yong He2022-08-22
|
* Support compile-time constant int val in the form of polynomials. (#2372)Yong He2022-08-22
| | | Co-authored-by: Yong He <yhe@nvidia.com>
* Warning on lossy implicit casts. (#2367)Yong He2022-08-17
| | | | | | | | | | | | | | | * Warning on bool to float conversion. * Fix test cases. * Improve. * LanguageServer: don't show constant value for non constant variables. * Fix tests. * Fix warnings in tests. Co-authored-by: Yong He <yhe@nvidia.com>
* Implicit pointer dereference when using member operator. (#2348)Yong He2022-08-04
| | | | | | | | | * Implicit pointer dereference when using member operator. * Add expected test result * Fix lookup. Co-authored-by: Yong He <yhe@nvidia.com>
* Major language server features. (#2264)Yong He2022-06-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * Major language server features. * Include slangd in binary release. * Fix compiler issues. * Fix compiler error. * Completion resolve. * Various improvements. * Update diagnostic test expected output. * Bug fix for source locations. * Adjust diagnostic update frequency. * Update github actions to store artifacts. * Fix infinite parser loop. * Fix parser recovery. * Fix parser recovery. * Update test. * Fix test. * Disable IR gen for language server. * Allow commit characters in auto completion. * Fix lookup for invoke exprs. * More parser robustness fixes. * update solution file Co-authored-by: Yong He <yhe@nvidia.com>
* Fix for default initialization with generic field (#2168)jsmall-nvidia2022-03-24
| | | | | | | | | | | | * #include an absolute path didn't work - because paths were taken to always be relative. * Fix for = {} initialization with a field that is generic type parameter. * Handling for if a non type is passed to a generic parameter which requires a type. * Small comment improvements. Fix some tab issues. * This fixes the matrix.slang issue. Move the matrix.slang test into bugs as generic-default-matrix.slang
* Fix the way extension declarations are cached for lookup (#1450)Tim Foley2020-07-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | During semantic checking, the compiler used to link together `ExtensionDecl`s into a singly-linked list dangling off of the `AggTypeDecl` that they applied to. This approach made lookup relatively easy, because given a `DeclRef` to an `AggTypeDecl` one could easily find and walk the list of candidate extensions. Unfortunately, the simple approach has two major strikes against it: * First, as we recently ran into, it creates a lifetime/ownership problem, in cases where the `ExtensionDecl` is outlived by the `AggTypeDecl` it applies to. This creates the one and only place in the compiler today where an "old" AST node might point to a "new" AST node, and it resulted in use-after-free problems in client code. * Second, the scoping of `extension`s ends up being completely wrong. All of the `extension` methods on a type end up being visible in all cases, instead of just in the context of modules where the `extension` itself is visible. The comparable feature in C# (static extension methods) is careful to not make scoping mistakes like this. The Swift langauge has loose scoping for `extension` more akin to what we have in Slang today, but the maintainers seem to consider it a misfeature. This change attempts to clean up both issues by changing the way that extension declarations are stored. There are two main pieces: 1. The primary "source of truth" for extension lookup has been moved to the `ModuleDecl`, where a module is responsible for storing a cache of the extensions declared within that module (keyed by the declaration of the type being extended). This cache is updated at the same point where the old code would mutate the AST node being depended on. 2. A secondary aggregated cache is added to the `SharedSemanticsContext` used during semantic checking. This cache includes entries from across multiple modules, and is intended to be invalidated and rebuilt on demand if new modules are added during checking. Access to the candidate extensions has now been put behind subroutines that require a semantics-checking context to be passed in (there was always one available in contexts that care about extensions). In addition, the operation for looking up members including those from extensions was refactored heavily to involve internal rather than external iteration and, more importantly, was changed so that it actually tests whether the `ExtensionDecl`s it loops over apply to the type in question, rather than blindly letting extensions members be looked up in ways that don't make sense. There are three test cases added here to confirm aspects of the fix: * First, I added a test that reproduces the crash that was being seen, so that we have a regression test for the fix. * Second, I added a basic semantic-checking test to confirm that an `extension` from an `import`ed module is still visible/usable, to confirm that I didn't break existing valid uses of extensions. * Third, I added a diagnostic test that ensures that we correctly ignore extensions that should not be visible in a given context as a result of `import` declarations. Co-authored-by: jsmall-nvidia <jsmall@nvidia.com>
* ASTNodes use MemoryArena (#1376)jsmall-nvidia2020-06-05
| | | | | | | | | | | | | | | | | | | | | | | | | | * Add a ASTBuilder to a Module Only construct on valid ASTBuilder (was being called on nullptr on occassion) * Add nodes to ASTBuilder. * Compiles with RefPtr removed from AST node types. * Initialize all AST node pointer variables in headers to nullptr; * Initialize AST node variables as nullptr. Make ASTBuilder keep a ref on node types. Make SyntaxParseCallback returns a NodeBase * Don't release canonicalType on dtor (managed by ASTBuilder). * Give ASTBuilders a name and id, to help in debugging. For now destroy the session TypeCache, to stop it holding things released when the compile request destroys ASTBuilders. * Moved the TypeCheckingCache over to Linkage from Session. * NodeBase no longer derived from RefObject. * Only add/dtor nodes that need destruction. First pass compile on linux.
* Feature/ast syntax standard (#1360)jsmall-nvidia2020-05-29
| | | | | | | | | * Small improvements to documentation and code around DiagnosticSink * Made methods/functions in slang-syntax.h be lowerCamel Removed some commented out source (was placed elsewhere in code) * Making AST related methods and function lowerCamel. Made IsLeftValue -> isLeftValue.
* WIP: ASTBuilder (#1358)jsmall-nvidia2020-05-28
| | | | | | | | | | | | | | | | | | * Compiles. * Small tidy up around session/ASTBuilder. * Tests are now passing. * Fix Visual Studio project. * Fix using new X to use builder when protectedness of Ctor is not enough. Substitute->substitute * Add some missing ast nodes created outside of ASTBuilder. * Compile time check that ASTBuilder is making an AST type. * Moced findClasInfo and findSyntaxClass (essentially the same thing) to SharedASTBuilder from Session.
* Improvements around hashing (#1355)jsmall-nvidia2020-05-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * Fields from upper to lower case in slang-ast-decl.h * Lower camel field names in slang-ast-stmt.h * Fix fields in slang-ast-expr.h * slang-ast-type.h make fields lowerCamel. * slang-ast-base.h members functions lowerCamel. * Method names in slang-ast-type.h to lowerCamel. * GetCanonicalType -> getCanonicalType * Substitute -> substitute * Equals -> equals ToString -> toString * ParentDecl -> parentDecl Members -> members * * Make hash code types explicit * Use HashCode as return type of GetHashCode * Added conversion from double to int64_t * Split Stable from other hash functions * toHash32/64 to convert a HashCode to the other styles. GetHashCode32/64 -> getHashCode32/64 GetStableHashCode32/64 -> getStableHashCode32/64 * Other Get/Stable/HashCode32/64 fixes * GetHashCode -> getHashCode * Equals -> equals * CreateCanonicalType -> createCanonicalType * Catches of polymorphic types should be through references otherwise slicing can occur. * Fixes for newer verison of gcc. Fix hashing problem on gcc for Dictionary. * Another fix for GetHashPos * Fix signed issue around GetHashPos
* Tidy up around AST nodes (#1353)jsmall-nvidia2020-05-22
| | | | | | | | | | | | | | | | | | | | | | | * Fields from upper to lower case in slang-ast-decl.h * Lower camel field names in slang-ast-stmt.h * Fix fields in slang-ast-expr.h * slang-ast-type.h make fields lowerCamel. * slang-ast-base.h members functions lowerCamel. * Method names in slang-ast-type.h to lowerCamel. * GetCanonicalType -> getCanonicalType * Substitute -> substitute * Equals -> equals ToString -> toString * ParentDecl -> parentDecl Members -> members
* Fix some bad behavior around static methods (#1289)Tim Foley2020-03-24
| | | | | | | | | | | | | | | These are steps towards a fix for the problem of not being able to call a static method as follows: SomeType::someMethod(); One problem in the above is that the parser gets confused and parses an (anonynmous!) function declaration. This change doesn't address that problem, but *does* fix the problem that when checking fails to coerce `SomeType::someMethod` into a type it was triggering an unimplemented-feature exception rather than a real error message. Another problem was that if the above is re-written to try to avoid the parser bug: (SomeType::someMethod)(); we end up with a call where the base expression (the callee) is a `ParenExpr` and the code for handling calls wasn't expecting that. Instead, it sent the overload resolution logic into an unimplemented case that was bailing by throwing an arbitrary C++ exception instead of emitting a diagnostic. This latter issue was fixed in two ways. First, the code path that failed to emit a diagnostic now emits a reasonable one for the unimplemented feature (this still ends up being a fatal compiler error). Second, we properly handle the case of trying to call a `ParenExpr` by unwrapping it and using the base expression instead, so that `(<func>)(<args>)` is always treated the same as `<func>(<args>)`.
* Fix a crash when a generic value argument isn't constant (#1241)Tim Foley2020-02-25
| | | | | | | | | | | | | | This arose when a user tried to specialize the DXR 1.1 `RayQuery` type to a local variable: ```hlsl RAY_FLAG rayFlags = RAY_FLAG_CULL_FRONT_FACING_TRIANGLES | RAY_FLAG_CULL_NON_OPAQUE; RayQuery<rayFlags> query; ``` In this case, we issued an error around `rayFlags` not being a constant as expected, but then we also crashes later on in checking because the `DeclRef` that was being used for the type had a null pointer for the generic argument corresponding to `rayFlags`. The main fix here was thus to add an `ErrorIntVal` case that can be used to represent something that should be an `IntVal` but where there was some kind of error in the input code so that the actual value isn't known to the compiler. A secondary fix here is that we were issuing error messages about expecting a constant for a parameter like `rayFlags` there *twice*, and one of those times was during the `JustChecking` part of overload resolution (when we are not supposed to emit any diagnostics). I fixed that up by allowing the `DiagnosticSink` to be used to be passed down explicitly (and allowing it to be null), while also leaving behind overloaded functions with the old signatures so that all the existing logic can continue to work unmodified.
* Support conversion from int/uint to enum types (#1147)Tim Foley2019-12-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * Support conversion from int/uint to enum types The basic feature here is tiny, and is summarized in the code added to the stdlib: ``` extension __EnumType { __init(int val); __init(uint val); } ``` The front-end already makes all `enum` types implicitly conform to `__EnumType` behind the scenes, and this `extension` makes it so that all such types inherit some initializers (`__init` declarations, aka. "constructors") that take `int` and `uint`. (Note: right now all `__init` declarations in Slang are assumed to be implemented as intrinsics using `kIROp_Construct`. This obviously needs to change some day, especially so that we can support user-defined initializers.) Actually making this *work* required a bit of fleshing out pieces of the compiler that had previously been a bit ad hoc to be a bit more "correct." Most of the rest of this description is focused on those details, since the main feature is not itself very exciting. When overload resolution sees an attempt to "call" a type (e.g., `MyType(3.0)`) it needs to add appropriate overload candidates for the initializers in that type, which may take different numbers and types of parameters. The existing code for handling this case was using an ad hoc approach to try to enumerate the initializer declarations to consider, which might be found via inheritance, `extension` declarations, etc. In practice, the ad hoc logic for looking up initializers was just doing a subset of the work that already goes into doing member lookup. Changing the code so that it effectively does lookup for `MyType.__init` allows us to look up initializers in a way that is consistent with any other case of member lookup. Generalizing this lookup step brings us one step closer to being able to go from an `enum` type `E` to an initializer defined on an `extension` of an `interface` that `E` conforms to. One casualty of using the ordinary lookup logic for initializers is that we used to pass the type being constructed down into the logic that enumerated the initializers, which made it easier to short-circuit the part of overload resolution that usually asks "what type does this candidate return." It might seem "obvious" that an initializer/constructor on type `Foo` should return a value of type `Foo`, but that isn't necessarily true. Consider the `__BuiltinFloatingPointType` interface, which requires all the built-in floating-point types (`float`, `double`, `half`) to have an initializer that can take a `float`. If we call that interface in a generic context for `T : __BuiltinFloatingPointType`, then we want to treat that initializer as returning `T` and not `__BuiltinFloatingPointType`. Without the ad hoc logic in initializer overload resolution, this is the exact problem that surfaced for the stdlib definition of `clamp`. The solution to the "what type does an initializer return" problem was to introduce a notion of a `ThisType`, which refers to the type of `this` in the body of an interface. More generally, we will eventually want to have the keyword `This` be the type-level equivalent of `this`, and be usable inside any type. The `calcThisType` function introduced here computes a reasonable `Type` to represent the value of `This` within a given declaration. Inside of concrete type it refers to the type itself, while in an `interface` it will always be a `ThisType`. The existing `ThisTypeSubstitution`s, previously only applied to associated types, now apply to `ThisType`s as well, in the same situations. The next roadblock for making the simple declarations for `__EnumType` work was that the lookup logic was only doing lookup through inheritance relationships when the type being looked up in was an `interface`. The logic in play was reasonable: if you are doing lookup in a type `T` that inherits from `IFoo`, then why bother looking for `IFoo::bar` when there must be a `T::bar` if `T` actually implements the interface? The catch in this case is that `IFoo::bar` might not be a requirement of `IFoo`, but rather a concrete method added via an `extension`, in which case `T` need not have its own concrete `bar`. The simple/obvious fix here was to make the lookup logic always include inherited members, even when looking up through a concrete type. Of course, if we allow lookup to see `IFoo::bar` when looking up on `T`, then we have the problem that both `T::bar` and `IFoo::bar` show up in the lookup results, and potentially lead to an "ambiguous overload" error. This problem arises for any interface rquirement (so both methods and associated types right now). In order to get around it, I added a somewhat grungy check for comparing overload candidates (during overload resolution) or `LookupResultItem`s (during resolution of simple overloaded identifiers) that considers a member of a concrete type as automatically "better" than a member of an interface. The Right Way to solve this problem in the long run requires some more subtlety, but for now this check should Just Work. One final wrinkle is that due to our IR lowering pass being a bit overzealous, we currently end up trying to emit IR for those new `__init` declarations, which ends up causing us to try and emit IR for a `ThisType`. That is a case that will require some subtlty to handle correctly down the line, for for now we do the expedient thing and emit the `ThisType` for `IFoo` as `IFoo` itself, which is not especially correct, but doesn't matter since the concrete initializer won't ever be called. * testing: add more debug output to Unix process launch function * testing: increase timeout when running command-line tests
* Further refactoring of semantic checking (#1102)Tim Foley2019-11-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * Split apart `SemanticsVisitor` The existing `SemanticsVisitor` type was the visitor for expressions, statements, and declarations, and its monolithic nature made it hard to introduce distinct visitors for different phases of checking (despite the fact that we had, de facto, multiple phases of declaration checking). This change splits up `SemanticsVisitor` as follows: * There is nosw a `SharedSemanticsContext` type which holds the shared state that all semantics visiting logic needs. This includes state that gets mutated during the course of semantic checking. * The `SemanticsVisitor` type is now a base class that holds a pointer to a `SharedSemanticsContext`. Most of the non-visitor functions are still defined here, just to keep the code as simple as possible. The `SemanticsVisitor` type is no longer a "visitor" in any meaningful way, but retaining the old name minimizes the diffs to client code. * There are distinct `Semantics{Expr|Stmt|Decl}Visitor` types that have the actual `visit*` methods for an appropriate subset of the AST hierarchy. These all inherit from `SemanticsVisitor` primarily so that they can have easy access to all the helper methods it defines (which used to be accessible because these were all the same object). Any client code that was constructing a `SemanticsVisitor` now needs to construct a `SharedSemanticsContext` and then use that to initialize a `SemanticsVisitor`. Similarly, any code that was using `dispatch()` to invoke the visitor on an AST node needs to construct the appropriate sub-class and then invoke `dispatch()` on it instead. This is a pure refactoring change, so no effort has been made to move state or logic onto the visitor sub-types even when it is logical. Similarly, no attempt has been made to hoist any code out of the common headers to avoid duplication between `.h` and `.cpp` files. Those cleanups will follow. The one cleanup I allowed myself while doing this was getting rid of the `typeResult` member in `SemanticsVisitor` that appears to be a do-nothing field that got written to in a few places (for unclear reasons) but never read. * Remove some statefulness around statement checking Some of the state from the old `SemanticsVisitor` was used in a mutable way during semantic checking: * The `function` field would be set and the restored when checking the body of a function so that things like `return` statements could find the outer function. * The `outerStmts` list was used like a stack to track lexically surrounding statements to resolve things like `break` and `continue` targets. Both of these meant that semantic checking code was doing fine-grained mutations on the shared semantic checking state even though the statefullness wasn't needed. This change moves the relevant state down to `SemanticsStmtVisitor`, which is a type we create on-the-fly to check each statement, so that we now only need to establish the state once at creation time. The list of outer statements is handled as a linked list threaded up through the stack (a recurring idiom through the codebase). There was one place where the `function` field was being used that wasn't strictly inside statement checking: it appears that we were using it to detect whether a variable declaration represents a local, so I added an `_isLocalVar` function to serve the same basic purpose. With this change, the only stateful part of `SharedSemanticsContext` is the information to track imported modules, which seems like a necessary thing (since deduplication requires statefullness). * Refactor declaration checking to avoid recursion The flexiblity of the Slang language makes enforcing ordering on semantic checking difficult. In particular, generics (including some of the built-in standard library types) can take value arguments, so that type expressions can include value expressions. This means that being able to determine the type of a function parameter may require checking expressions, which may in turn require resolving calls to an overloaded function, which in turn requires knowing the types of the parameters of candidate callees. Up to this point there have been two dueling approaches to handling the ordering problem in the semantic checking logic: 1. There was the `EnsureDecl` operation, supported by the `DeclCheckState` type. Every declaration would track "how checked" it is, and `EnsureDecl(d, s)` would try to perform whatever checks are needed to bring declaration `d` up to state `s`. 2. There was top-down orchestration logic in `visitModuleDecl()` that tried to perform checking of declarations in a set of fixed phases that ensure things like all function declarations being checked before any function bodies. Each of these options had problems: 1. The `EnsureDecl()` approach wasn't implemented completely or consistently. It only understood two basic levels of checking: the "header" of a declaration was checked, and then the "body," and it relied on a single `visit*()` routine to try and handle both cases. Things ended up being checked twice, or in a circular fashion. 2. Rather than fix the problems with `EnsureDecl()` we layered on the top-down orchestration logic, but doing so ignores the fact that no fixed set of phases can work for our language. The orchestration logic was also done in a relatively ad hoc fashion that relied on using a single visitor to implement all phases of checking, but it added a second metric of "checked-ness" that worked alongside `DeclCheckState`. This change strives to unify the two worlds and make them consistent. One of the key changes is that instead of doing everything through a single visitor type, we now have distinct visitors for distinct phases of semantic checking, and those phases are one-to-one aligned with the values of the `DeclCheckState` type. More detailed notes: * Existing sites that used to call `checkDecl` to directly invoke semantic checking recursively now use `ensureDecl` instead. This makes sure that `ensureDecl` is the one bottleneck that everything passes through, so that it can guarantee that each phase of checking gets applied to each declaration at most once. * The existing `visitModuleDecl` was revamped into a `checkModule` routine that does the global orchestration, but now it is just a driver routine that makes sure `ensureDecl` gets called on everything in an order that represents an idealized "default schedule" for checking, while not ruling out cases where `ensureDecl()` will change the ordering to handle cases where the global order is insufficient. * Because `checkModule` handles much of the recursion over the declaration hierarchy, many cases where a declaration `visit*()` would recurse on its members have been eliminated. The only case where a declaration should recursively `ensureDecl()` its members is when its validity for a certain phase depends on those members being checked (e.g., determining the type of a function declaration depends on its parameters having been checked). * All cases where a `visit*()` routine was manually checking the state/phase of checking have been eliminated. It is now the responsibility of `ensureDecl` to make sure that checking logic doesn't get invoked twice or in an inappropriate order. * Most cases where a `visit*()` routine was manually *setting* the `DeclCheckState` of a declaration have been eliminated. The common case is now handled by `ensureDecl()` directly, and `visit*()` methods only need to override that logic when special cases arise. E.g., when a variable is declared without a type `(e.g., `let foo = ...;`) then we need to check its initial-value expression to determine its type, so that we must check it further than was initially expected/required. * This change goes to some lengths to try and keep semantic checking logic at the same location in the `slang-check-decl.cpp` file, so each of the per-phase visitor types is forward declared at the top of the file, and then the actual `visit*()` routines are interleaved throughout the rest of the file. A future change could do pure code movement (no semantic changes) to arrive at a more logical organization, but for now I tried to stick with what would minimize the diffs (although the resulting diffs can still be messy at times). * One important change to the semantic checking logic was that the test for use of a local variable ahead of its declaration (or as part of its own initial-value expression) was moved around, since its old location in the middle of the `ensureDecl` logic made the overall flow and intention of that function less clear. There is still a need to fix this check to be more robust in the future. * Add some design documentation on semantic checking The main thing this tries to lay out is the strategy for declaration checking and the rules/constraints on programmers that follow from it. * fixup: typos found during review
* Refactor semantic checking code into more files (#1097)Tim Foley2019-10-25
The semantic checking logic was all inside `slang-check.cpp` and as a result this was a monster file that was extremely hard to follow. This change splits `slang-check.cpp` into several smaller files, although some of the resulting files are still quite large. This change attempts to be a copy-paste job as much as possible and does *not* perform any cleanup on naming, structure, duplication, etc. in the code it deal with. No function bodies or signatures have been touched.