Will any government - or legal framework applicable to more than, let's say, 1 million people - provide legal rights (along the lines of a right to exist) to an intelligence based on silicon?
This could be, e.g., an AI or a full/partial brain upload from a biological intelligence.
This might need some finessing and I'm not a lawyer. The spirit of the question is, broadly, when will the existence of intelligence existing within a computer be sufficiently established that society deems it worthy of legal recognition?
A brain upload from biological intelligence , you mean the same technology mentioned in the TV series Pantheon right? I think it's doable if less moral or ethical boundaries are set for the experiment, however in reality that's hard, humans are afraid of death and ethic challenges which means such experiment like Brain upload would be prohibited in the first place. At least it's not going to happen before 2050 from my point of view.
I wouldn't assume computers in 2050 – especially quantum ones – are still made of silicon. I went to check and apparently present-day quantum chips are also made of silicon, but I don't think that's necessary.
If the spirit of the question is about intelligences based on artificial substrates, write that as the title of the question ;)