WG21 PAPERS

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Select	Paper	Title	Authors	Audience
	P2929R4	chunked_invoke	D. Towner, R. Arutyunyan	LEWG
Mailing Date 2026-05 Pre-Brno Author(s) Daniel Towner, Ruslan Arutyunyan Target Audience LEWG Revisions R3 R2 Tracking issue View on GitHub Abstract ISO/IEC 19570:2018 introduced data-parallel types to the C++ Extensions for Parallelism TS [P1928R15]. That paper, and several ancillary papers, do an excellent job of setting out the main features of an extension to C++ which allows generic data parallel programming on arbitrary targets. However, it is inevitable that the programmer will want to make some use of target-specific intrinsics, or cal
	P2964R4	Allowing user-defined types in std::simd	D. Towner, R. Arutyunyan	LEWG SG6
Mailing Date 2026-05 Pre-Brno Author(s) Daniel Towner, Ruslan Arutyunyan Target Audience LEWG SG6 Revisions R5 R3 R2 Tracking issue View on GitHub Abstract The C++ standard library includes data-parallel types in the `<simd>` header, currently restricting element types to a closed list of built-in vectorizable types: arithmetic types and `std::complex` specializations. This paper proposes a minimal change to the specification in which this list is extended. Firstly, `std::byte` is added to the closed list as a standard library type with fixed seman
	P3971R1	Generalised type rebinding for structures of uniform elements	D. Towner	LEWG
Mailing Date 2026-05 Pre-Brno Author(s) Daniel Towner Target Audience LEWG Revisions R0 Tracking issue View on GitHub Abstract Modern C++ provides powerful facilities for generic programming, but lacks a uniform way to change the element type of containers and container-like types. Consider a simple requirement: convert a container of `float` into the corresponding container of `double`, without the caller having to know what kind of container it is.
	P3973R1	bit_cast_as: Element type reinterpretation for std::simd	D. Towner	LEWG
Mailing Date 2026-05 Pre-Brno Author(s) Daniel Towner Target Audience LEWG Revisions R0 Tracking issue View on GitHub Abstract SIMD programming frequently requires reinterpreting vector data at different element granularities—converting packed bytes to shorts, accessing the bit representation of floats, or regrouping data for different operations. While platform intrinsics have long supported this pattern naturally, with `std::simd` programmers must use `std::bit_cast` with fully-specified target types, manually computing
	P3983R2	simd object representation	D. Towner, R. Arutyunyan	LEWG LWG SG1
Mailing Date 2026-05 Pre-Brno Author(s) Daniel Towner, Ruslan Arutyunyan Target Audience LEWG LWG SG1 Revisions R1 R0 Tracking issue View on GitHub Abstract The Working Draft makes `simd` types trivially copyable types, which allows `std::bit_cast` operations. However, the object representation is unspecified, making the results similarly unspecified.
	P4209R0	numeric_limits for std::simd	D. Towner	LEWG SG6
Mailing Date 2026-05 Pre-Brno Author(s) Daniel Towner Target Audience LEWG SG6 Tracking issue View on GitHub Abstract The SIMD working draft introduces `std::simd::basic_vec<T, Abi>` as an element-wise parallel extension of an element type `T`. A central goal is to allow the same generic numeric code to operate on scalar `T` and on `basic_vec<T, Abi>` interchangeably. Most non-trivial numeric code that aims for that behaviour would require `std::numeric_limits<V>` somewhere. For example:

Showing 6 of 6 papers · source: open-std.org

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