[workstream] Language

[damyanp]

Specification and implementation of the HLSL language.

This workstream tracks the specification and implementation of HLSL's grammar,
semantics and built-in functionality. Many other workstreams will contribute
design and implementation for language features, for those cases this workstream
merely tracks the dependency not the ongoing work.

Milestones

Compile a runnable shader from clang (#7)

• numthreads entry attribute
• Entry function linkage rules

Compile particle_life.hlsl (#20)

• Basic type declarations (e.g. uint, int, half, ...)
• Vector type declarations (e.g. vector<T,N>, float3, int4, ...)
• Vector cast-construction syntax (e.g. float3(x,x,x))
• Internal function linkage rules
• cbuffer declarations
• [HLSL] bitcasts emitted instead of vector conversions in binary operators llvm-project#106253

Compile a broad selection of compute shaders (#11)

• Identify remaining language features for DirectML
• [HLSL] vector subscript indexing llvm-project#91640
• [HLSL] Copy in/copy out parameter passing llvm-project#87526 (out and inout keywords)
• HLSL initializer list support llvm-project#56067
• [HLSL] Crash using array parameters llvm-project#125743
• [HLSL] [branch] attribute support for switch statements llvm-project#125754

Render Simple Triangle (#13)

• Semantic language components TBD (see Semantics workstream)

Render Mesh (#15)

• Matrix language components TBD (see Matrix workstream)

Pixel and Vertex Shaders (#16)

• Barycentric Design

Mesh Shaders (#17)

• DispatchMesh address space and uniformity design
• [HLSL] precise keyword for floating point types llvm-project#100776

Ray Tracing (#18)

• Full design for library shader linkage model

V1 Release (#19)

• Draft specification completed

External References

• HLSL-Specs Language Spec Issues
• Latest Draft Specification PDF