DirectX Shader Compiler: vanhemmat versiot ja versiohistoria

DXC Release Highlights
This release of the DirectX Shader Compiler (DXC) includes HLSL language updates, SPIR-V backend improvements, compiler correctness and stability fixes, and corrections to the Windows and Linux release packages.

HLSL Language
- Updated [unroll(N)] behavior for HLSL 202x so the count acts as a partial-unroll hint rather than limiting loop iterations.
- Added the -Whlsl-2026-compat warning group to help identify compatibility issues introduced by HLSL 2026.
- Improved diagnostics for invalid resource-containing casts and removed legacy effects syntax from HLSL 202x.

SPIR-V Backend Improvements
- Expanded support for inline SPIR-V attributes and globallycoherent resource-heap accesses.
- Corrected code generation for buffer-pointer bitfields, raw-buffer alignment, and older SPIR-V versions.
- Fixed crashes involving RayQuery type shadowing and static members of constant and texture buffers.

Compiler Quality and Stability
- Fixed derivative operations being incorrectly moved into divergent control flow.
- Fixed several crashes and assertions involving templates, dynamic resource heaps, and ray-payload member methods.

Release Packaging (Regressions)
- Fixed Windows ARM64 import libraries so native ARM64 applications can link against dxcompiler.lib.
- Corrected the Linux release archive to contain only shipping files, which includes the expected headers again.

More Details
This DXC release is also available as the Microsoft.Direct3D.DXC NuGet package.
For the complete itemized list of changes and technical details, see ReleaseNotes.md.

## DXC Release Highlights

This release of the DirectX Shader Compiler (DXC) adds production support for Shader Model 6.9,
along with broad correctness, stability, and SPIR-V backend improvements.

For an overview of the Shader Model 6.9 feature set and motivation, see:

- The official DX blog post
- Shader Model 6.9 and the Future of Cooperative Vector blog post

## SPIR-V Backend Improvements

This release includes significant SPIR-V backend updates focused on:

- Improved layout and ABI correctness, including scalar layout rules and structure layout
consistency.
- Expanded type system support, including templates and richer pointer-based types.
- Better code generation correctness for arithmetic, control flow, and resource access.
- Ongoing improvements to debug information emission for SPIR-V targets.

These changes improve interoperability with Vulkan drivers and tooling while aligning behavior more
closely with HLSL and DXIL semantics.

## Compiler Quality and Stability

In addition to new feature support, this release delivers:

- Numerous compiler correctness fixes across HLSL front-end, DXIL, and SPIR-V paths.
- Improved handling of edge cases in constant buffers, resources, and control flow.
- General stability and reliability improvements when compiling complex shaders.

## More Details

This DX compiler release is also available as a NuGet package Microsoft.Direct3D.DXC.

The new DirectX 12 Agility SDK and a hardware driver with appropriate support are required to run
shader model 6.9 shaders. Please see https://aka.ms/directx12agility for details.

For an itemized list of changes, fixes, and technical details, see the full release notes:

- ReleaseNotes.md