)

Historically, HIP and ROCm versions were interchangeable, but moving forward these versions are allowed to diverge.  ROCm version represents the full ROCm software stack, while HIP is a component of the ROCm stack.

Issue #166068 was fixed by [switching from using HIP_VERSION to ROCM_VERSION_DEV](#166336).  However, this broke the build of ROCm apex because the hip version from `hipcc --version` no longer matched `torch.version.hip`.  This highlights the need for both versions to be exposed.

Bitsandbytes has also been impacted by the change in behavior of `torch.version.hip`: bitsandbytes-foundation/bitsandbytes#1799 (comment)

The solution is to fix the `torch.version.hip` so that it uses the hipcc header values and removes the trailing hash code. In addition, `torch.version.rocm` variable is created to store the ROCm version.

## Technical Details

### Fix torch.version.hip

HIP_VERSION variable is computed in https://github.com/ROCm/hip/blob/develop/cmake/FindHIP.cmake. This runs hipcc –version and extracts the output of HIP version line, e.g.,
```
hipcc --version
HIP version: 7.1.25421-32f9fa6ca5
```

The HIP_VERSION variable may contain a hash code at the end.  This trailing hashcode is removed from the HIP_VERSION variable so that the torch.version.hip can be parsed by packaging version parse method, e.g.,
```
import torch
from packaging import version
print(version.parse(torch.version.hip))
```

### Add torch.version.rocm

Code changes:
- Add rocm variable to torch/version.py.tpl
- Add code to write rocm variable in tools/generate_torch_version.py
- Write rocm version in installation process - torch/CMakeLists.txt

## Testing

Tested on a preview of ROCm 7.2.  Successfully built pytorch and apex. Tested above parsing torch.version.hip code.

```
>>> import torch
>>> torch.version.hip
'7.1.25421'
>>> torch.version.rocm
'7.2.0'
```

Pull Request resolved: #168097
Approved by: https://github.com/jeffdaily

Co-authored-by: Jeff Daily <jeff.daily@amd.com>