<feed xmlns='http://www.w3.org/2005/Atom'>
<title>slang.git/source/slang/slang-syntax.h, branch master</title>
<subtitle>Making it easier to work with shaders</subtitle>
<id>https://git.yummers.dev/slang.git/atom?h=master</id>
<link rel='self' href='https://git.yummers.dev/slang.git/atom?h=master'/>
<link rel='alternate' type='text/html' href='https://git.yummers.dev/slang.git/'/>
<updated>2025-10-07T00:21:37+00:00</updated>
<entry>
<title>Use symbol alias instead of wrapper synthesis to implement link-time types. (#8603)</title>
<updated>2025-10-07T00:21:37+00:00</updated>
<author>
<name>Yong He</name>
<email>yonghe@outlook.com</email>
</author>
<published>2025-10-07T00:21:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.yummers.dev/slang.git/commit/?id=6af3381f47e3c22e1657c0e0064fa466e8bde0f6'/>
<id>urn:sha1:6af3381f47e3c22e1657c0e0064fa466e8bde0f6</id>
<content type='text'>
This change achieves link-time type resolution with a different
mechanism.

For `extern struct Foo : IFoo = FooImpl;`,
instead of synthesizing a wrapper type `Foo` that has a `FooImpl inner`
field and dispatches all interface method calls to `inner.method()`,
this PR completely removes this synthesis step, and instead just lower
such `extern`/`export` types as `IRSymbolAlias` instructions that is
just a reference to the type being wrapped.

Then we extend the linker logic to clone the referenced symbol instead
of the SymbolAlias insts itself during linking.

By doing so, we greatly simply the logic need to support link-time
types, and achieves higher robustness by not having to deal with many
AST synthesis scenarios.

Closes #8554.

---------

Co-authored-by: slangbot &lt;186143334+slangbot@users.noreply.github.com&gt;</content>
</entry>
<entry>
<title>Rename some symbols related to pointers types (#8592)</title>
<updated>2025-10-03T04:48:11+00:00</updated>
<author>
<name>Theresa Foley</name>
<email>10618364+tangent-vector@users.noreply.github.com</email>
</author>
<published>2025-10-03T04:48:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.yummers.dev/slang.git/commit/?id=cc8f6a241edb47c43c5698ee33abed4fe57d4566'/>
<id>urn:sha1:cc8f6a241edb47c43c5698ee33abed4fe57d4566</id>
<content type='text'>
Note that while this change touched a large numer of files, there are no
changes to functionality being made here. The only things being done are
renaming various symbols and, in a few cases, updating or adding
comments for consistency with the new names.

The core of the naming changes are:

* Most things named to refer to `OutType` (e.g., `IROutType`,
`IRBuilder::getOutType()`, etc.) have been consistently renamed to refer
to `OutParamType`, to emphasize that the relevant AST/IR node types are
only intended for use to represent `out` parameters.

* The same change as described above for `OutType` is also made for
`RefType`, which becomes `RefParamType` in most cases. One mess that
this exposes is the way that the `ExplicitRef&lt;T&gt;` type in the core
module currently lowers to `IRRefParamType`. This change sticks to the
rule of not making functional changes, so that mess is left as-is for
now.

* Names referring to `InOutType` have been changed to instead refer to
`BorrowInOutType`. The intention with this naming change is to emphasize
that the Slang rules for `inout` are semantically those of a borrow (or
at least our interpretation of what a borrow means).

* Names referring to `ConstRefType` have been changed to instead refer
to `BorrowInType`. This change starts work on clarifying that the
existing `__constref` modifier was never intended to be a read-only
analogue of `__ref`, and instead is the input-only analogue of `inout`.

* The `ParameterDirection` enum type has been changed to
`ParamPassingMode`, to reflect the fact that the concept of "direction"
fails to capture what is actually being encoded, particularly once we
have modes beyond simple `in`/`out`/`inout`.

While this change does not alter behavior in any case (the user-exposed
Slang language is unchanged), it is intended to set up subsequence
changes that will work to make the handling of these types in the
compiler more nuanced and correct. Breaking this part of the change out
separately is primarily motivated by a desire to minimize the effort for
reviewers.

---------

Co-authored-by: slangbot &lt;186143334+slangbot@users.noreply.github.com&gt;</content>
</entry>
<entry>
<title>Allow interface methods to have default implementations. (#7439)</title>
<updated>2025-06-14T05:13:00+00:00</updated>
<author>
<name>Yong He</name>
<email>yonghe@outlook.com</email>
</author>
<published>2025-06-14T05:13:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.yummers.dev/slang.git/commit/?id=6a23949f07f4eba38086b656e7073ce3bf8cd2fe'/>
<id>urn:sha1:6a23949f07f4eba38086b656e7073ce3bf8cd2fe</id>
<content type='text'>
</content>
</entry>
<entry>
<title>Mediate access to ContainerDecl members (#7242)</title>
<updated>2025-06-09T18:22:51+00:00</updated>
<author>
<name>Theresa Foley</name>
<email>10618364+tangent-vector@users.noreply.github.com</email>
</author>
<published>2025-06-09T18:22:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.yummers.dev/slang.git/commit/?id=bfae49d853e0f9b6f9de495b13bcd1642ca4a285'/>
<id>urn:sha1:bfae49d853e0f9b6f9de495b13bcd1642ca4a285</id>
<content type='text'>
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.</content>
</entry>
<entry>
<title>Initial support for immutable lambda expressions. (#6914)</title>
<updated>2025-04-30T21:17:45+00:00</updated>
<author>
<name>Yong He</name>
<email>yonghe@outlook.com</email>
</author>
<published>2025-04-30T21:17:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.yummers.dev/slang.git/commit/?id=7f1df9d0b31413e59846cc955d2a955d3f361e2a'/>
<id>urn:sha1:7f1df9d0b31413e59846cc955d2a955d3f361e2a</id>
<content type='text'>
* Initial support for immutable lambda expressions.

* More diagnostics, and langauge server fix.

* Language server fix.

* Fix bug identified in review.

* Add expected result.

* Update expected result.</content>
</entry>
<entry>
<title>A new approach to AST serialization (#6854)</title>
<updated>2025-04-22T20:26:57+00:00</updated>
<author>
<name>Theresa Foley</name>
<email>10618364+tangent-vector@users.noreply.github.com</email>
</author>
<published>2025-04-22T20:26:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.yummers.dev/slang.git/commit/?id=1cf3f18a9ca1905a5bc51790ca723815dd5b1400'/>
<id>urn:sha1:1cf3f18a9ca1905a5bc51790ca723815dd5b1400</id>
<content type='text'>
* 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&lt;Expr,R&gt;(expr, [&amp;](auto e) { return doSomething(e); })
```

is an expression of type `R`, which does the equivalent of something like:

```
switch(expr-&gt;getTag())
{
case ASTNodeType::VarExpr: return doSomething(static_cast&lt;VarExpr*&gt;(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 &lt;186143334+slangbot@users.noreply.github.com&gt;
Co-authored-by: Yong He &lt;yonghe@outlook.com&gt;</content>
</entry>
<entry>
<title>Fix requirement candidate lookup to prefer decls in the same paraent as the inheritance decl. (#5965)</title>
<updated>2024-12-31T07:38:34+00:00</updated>
<author>
<name>Yong He</name>
<email>yonghe@outlook.com</email>
</author>
<published>2024-12-31T07:38:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.yummers.dev/slang.git/commit/?id=88e221bad60ce20087fe2f8a85d506be36a6e6ca'/>
<id>urn:sha1:88e221bad60ce20087fe2f8a85d506be36a6e6ca</id>
<content type='text'>
</content>
</entry>
<entry>
<title>format</title>
<updated>2024-10-29T06:49:26+00:00</updated>
<author>
<name>Ellie Hermaszewska</name>
<email>ellieh@nvidia.com</email>
</author>
<published>2024-10-29T06:49:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.yummers.dev/slang.git/commit/?id=f65d756bff8d4c5cbc15bd0322a2ae8e6b896a21'/>
<id>urn:sha1:f65d756bff8d4c5cbc15bd0322a2ae8e6b896a21</id>
<content type='text'>
* format

* Minor test fixes

* enable checking cpp format in ci</content>
</entry>
<entry>
<title>Properly check switch case. (#5341)</title>
<updated>2024-10-20T16:28:13+00:00</updated>
<author>
<name>Yong He</name>
<email>yonghe@outlook.com</email>
</author>
<published>2024-10-20T16:28:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.yummers.dev/slang.git/commit/?id=307315a7305e76529837fd1cdb677f534d5f539b'/>
<id>urn:sha1:307315a7305e76529837fd1cdb677f534d5f539b</id>
<content type='text'>
</content>
</entry>
<entry>
<title>Add ability to specialize generic references to functions, types and more (#4909)</title>
<updated>2024-08-27T20:47:05+00:00</updated>
<author>
<name>Sai Praveen Bangaru</name>
<email>31557731+saipraveenb25@users.noreply.github.com</email>
</author>
<published>2024-08-27T20:47:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.yummers.dev/slang.git/commit/?id=4aac22da6ae902eca1e7750f4e5b83ba238b5874'/>
<id>urn:sha1:4aac22da6ae902eca1e7750f4e5b83ba238b5874</id>
<content type='text'>
* More reflection API features.

+ Lookup methods and members (by string) on types
+ Fix issue with looking up non-static members through the scope operator '::'
+ `GenericReflection`: Cast a decl to generic to access unspecialized generic parameter names and constraints
+ `GenericReflection`: Use `getGenericContainer()` from function, variable or type to access the 'nearest' generic parent along with specialization info
+ `GenericReflection::getConcreteType` and `GenericReflection::getConcreteIntVal`: to get the concrete type of a param in the context of the reflection object
+ `GenericReflection::getOuterGenericContainer` to go up one level and get the outer generic declarations (if there are more than one enclosing generic scopes)
+ `DeclReflection::getParent`: go to parent declaration.
+ Change `VariableReflection` to be a `DeclRef` rather than a decl (allows us to return properly substituted types for methods, members, and more)

* Fix Falcor issue

* Initial namespace reflection support

* FIx issue with specializing witness tables

* Add API method for specializing parameters of a generic decl

* Add ability to specialize generic references to functions, types and more

This PR adds the following end-points:

- `specializeGeneric()` method that can be called on a generic reflection to substitute arguments for generic type and value parameters. It returns another generic reflection, but this time with the appropriate substitution.
- `applySpecializations()` method to then copy these specializations onto an existing type or function reflection.
- `isSubType()` to check if a type is a subtype of another type (useful to check if a type is differentiable by checking `IDifferentiable`)

This PR also:
 - Adds `DeclReflection::Kind::Namespace` so that namespace containers are correctly reflected when walking the decl-tree. the name can be obtained through `getName()` but there's no need to cast to a namespace (since there's nothing else we can do with a namespace decl)
 - Fixes an issue with name-based lookups that fail if a type or function is referenced without specializations. Its helpful to be able to form a reference to a function with default substitutions, so that we can we can specialize it later (either directly, or via argument types).

* Update slang.h

* Fix up naming

* Update slang-compiler.h

* Update slang-reflection-api.cpp

* Update slang.cpp

* Update slang.cpp

* Update slang.cpp

* Use `checkGenericAppWithCheckedArgs` to do specialization

* Update slang-reflection-api.cpp

* Update slang-check-decl.cpp</content>
</entry>
</feed>
