[Feature Request] Add shader model 5 support and DXBC bytecode output

[djdron]

The problem is what we need open source shader compiler for DX11/DXVK native for Linux.

We'd like solution to have cross-platform dxcompiler.dll/.so. Instead of d3dcompiler_XX.dll & ugly wine implementation.

Considered alternative is to use original d3dcompiler_XX.dll from Microsoft with wine. But we need native DXVK build with HLSL compiler for Linux.

[gongminmin]

It has been mentioned several times. For example, #621. There is a WIP work to add DXBC back-end to Mesa https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/14253, but doesn't in active developing. In theory that back-end can be ported to DXC.

[llvm-beanz]

DXC's fork of LLVM removed and/or damaged much of the code generation layer and infrastructure. Given that, supporting DXBC generation in DXC would be a massive task to fix and restore broken LLVM functionality. Due to the large scale of this issue and resource constraints on our team we're not going to address this issue in DXC ever.

We may support DXBC generation in Clang in the future (we mentioned that in the original proposal to LLVM). That work is unlikely to begin for a few years as our focus will be on supporting DXIL and SPIR-V generation first.