Report: MPS backend is working fine

[KanTakahiro]

I just add some codes for using BERTScore on Apple Silicon and it works fine. I think MPS support should be add to the code base for Mac users' convenience.

I tested MPS backend by this: score(candidates, references, lang="ja", device="mps")

Basically I added MPS detection code below every CUDA detection code.

in score.py:

    if device is None:
        device = "cuda" if torch.cuda.is_available() else "cpu"
        device = "mps" if torch.backends.mps.is_available() else "cpu"    # added to line 101
    model.to(device)

    device = "cuda" if torch.cuda.is_available() else "cpu"
    device = "mps" if torch.backends.mps.is_available() else "cpu"    # added to line 242
    model.to(device)

in scorer.py:

        if device is None:
            self.device = "cuda" if torch.cuda.is_available() else "cpu"
            self.device = "mps" if torch.backends.mps.is_available() else "cpu"    # added to line 74
        else:
            self.device = device

in utils.py:

    device = "mps" if torch.backends.mps.is_available() else "cpu"    # added to line 409 & 446 & 605

My environment:

Apple M1
macOS 14.5
Python 3.12
torch 2.3.0
bert-score 0.3.13