[llvm] [SPIRV] Add FPVariant tracking for floating-point registers in SPIR-V (PR #156871)

[via llvm-commits]

YixingZhang007 wrote:

The current CI failure in `SPIRV-V Tests / Test SPIR-V` is due to the test failure in `CodeGen/SPIRV/instructions/integer-casts.ll`. I think this failure is not related to the changes introduced in this PR. I had temporarily commented out all modifications, and this test still failed. The commit reverting all changes can be found at https://github.com/llvm/llvm-project/pull/156871/commits/a67050e7d47c853c5721e08a7990eef34c4e25f2, and its corresponding `SPIRV-V Tests / Test SPIR-V` failure can be found at https://github.com/llvm/llvm-project/actions/runs/17502517326/job/49718552664.

https://github.com/llvm/llvm-project/pull/156871