[Bugfix] fix detokenizer shallow copy

[aurickq]

Quick bugfix for Detokenizer.decode_prompt_logprobs_inplace when prev_tokens can blow up exponentially due to it being the same reference as next_iter_tokens

FIX #xxxx (link existing issues this PR will resolve)

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[aurickq]

@Yard1

[zifeitong]

Hi,

About

prev_tokens can blow up exponentially due to it being the same reference as next_iter_tokens

What's the behavior you are seeing? Is it caused by the bug fixed in #5846?

Thanks!

[aurickq]

Hi,

About

prev_tokens can blow up exponentially due to it being the same reference as next_iter_tokens

What's the behavior you are seeing? Is it caused by the bug fixed in #5846?

Thanks!

It sounds related. I found this condition token_id == all_token_ids[token_position] didn't get triggered which caused the issue described in this PR. Does #5846 also fix this issue?

[zifeitong]

Hi,
About

prev_tokens can blow up exponentially due to it being the same reference as next_iter_tokens

What's the behavior you are seeing? Is it caused by the bug fixed in #5846?
Thanks!

It sounds related. I found this condition token_id == all_token_ids[token_position] didn't get triggered which caused the issue described in this PR. Does #5846 also fix this issue?

I believe so. The exponentially growth will be triggered in scenarios described in #5846 (comment)

[aurickq]

Hi,
About

prev_tokens can blow up exponentially due to it being the same reference as next_iter_tokens

What's the behavior you are seeing? Is it caused by the bug fixed in #5846?
Thanks!

It sounds related. I found this condition token_id == all_token_ids[token_position] didn't get triggered which caused the issue described in this PR. Does #5846 also fix this issue?

I believe so. The exponentially growth will be triggered in scenarios described in #5846 (comment)

Unfortunately it still doesn't seem to be fixed for me. I'll try to get a minimal example