[clang] [Clang][SYCL] Introduce clang-sycl-link-wrapper to link SYCL offloading device code (Part 1 of many) (PR #112245)

[Joseph Huber via cfe-commits]

jhuber6 wrote:

> LLD has a wasm target.

Exactly what I meant.

> I think LLD also needs to eventually gain a SPIR-V target to support linking SPIR-V binaries, because SPIR-V does support linkage at the SPIR-V level not just the LTO IR level (see: https://registry.khronos.org/SPIR-V/specs/unified1/SPIRV.html#_linkage). I certainly know that my team will want to use lld as the LTO driver for DXIL and SPIR-V when targeting DirectX and Vulkan with HLSL.

Yeah I would like if you could link direct SPIR-V, i think right now that's done with an external tool? Using `lld` would be the logical place to put that. I just mean that we can introduce simpler solutions and then work to more complete ones. That seems like a more complete issue than what we're doing here though. (Also I don't have the most complete picture for what special things SYCL needs to do here. Hopefully they can chime in but IIRC it has to do with merging several images / binaries into some logical set so it's not as simple as linking?).

https://github.com/llvm/llvm-project/pull/112245