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Exercises in Emulation: Xbox 360’s FMA Instruction

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Re: Exercises in Emulation: Xbox 360’s FMA Instruction

#2
> If you apply for a mortgage when your job title is emulation ninja then you are in a quandary. If you write that on the mortgage application then you look like a lunatic. If you write “software engineer” then you get in trouble when the mortgage broker calls your employer. You know. Hypothetically.

Re: Exercises in Emulation: Xbox 360’s FMA Instruction

#3
> I left the Xbox team long before the Xbox One shipped and I haven’t paid any attention to it since then, so I don’t know what they decided to do.

From experience trying to play 360 games on an Xbox One, the console reads nothing from the DVD and instead downloads the game from the Internet. It also only works for specific games. I therefore assume they gave up with emulation and simply recompiled certain 360 games for x64.

Re: Exercises in Emulation: Xbox 360’s FMA Instruction

#4
As far as I know, a correct emulation of FMA involves the double-double approach [1], that is to split a logical mantissa potentially larger than the native mantissa and merge them later. This is of course expensive and probably not a good fit for the OP's purpose anyway.

[1] https://hal-ens-lyon.archives-ouvertes.fr/inria-00080427v2/d... has a verified proof.

Re: Exercises in Emulation: Xbox 360’s FMA Instruction

#5

> If you apply for a mortgage when your job title is emulation ninja then you are in a quandary. If you write that on the mortgage application then you look like a lunatic. If you write “software engineer” then you get in trouble when the mortgage broker calls your employer. You know. Hypothetically.

Do mortgage brokers call your employer? What’s your mortgage got to do with your employer?

Re: Exercises in Emulation: Xbox 360’s FMA Instruction

#6
The whole time I was reading I was interested in what they chose to do... a lot of build up and no solution :/

Maybe they did recompile the games for backwards compatibility, maybe they do have an emulator, IDK, but I want to know how they would have fixed this issue.

Re: Exercises in Emulation: Xbox 360’s FMA Instruction

#7

> If you apply for a mortgage when your job title is emulation ninja then you are in a quandary. If you write that on the mortgage application then you look like a lunatic. If you write “software engineer” then you get in trouble when the mortgage broker calls your employer. You know. Hypothetically.

Do mortgage brokers call your employer? What’s your mortgage got to do with your employer?

Verifying the things you put on your mortgage application are true, like employment details.

Re: Exercises in Emulation: Xbox 360’s FMA Instruction

#8
post #3

> I left the Xbox team long before the Xbox One shipped and I haven’t paid any attention to it since then, so I don’t know what they decided to do. From experience trying to play 360 games on an Xbox One, the console reads nothing from the DVD and instead downloads the game from the Internet. It also only works for specific games. I therefore assume they gave up with emulation and simply recompiled certain 360 games…

Recompiling alone wouldn't help if the game engine's floating point were tuned for behavior of the PPC.

EDIT: I don't know if they did emulation or not - I always believed they did but only managed to certify some games.

Re: Exercises in Emulation: Xbox 360’s FMA Instruction

#9

> If you apply for a mortgage when your job title is emulation ninja then you are in a quandary. If you write that on the mortgage application then you look like a lunatic. If you write “software engineer” then you get in trouble when the mortgage broker calls your employer. You know. Hypothetically.

Do mortgage brokers call your employer? What’s your mortgage got to do with your employer?

Probably your income.

Re: Exercises in Emulation: Xbox 360’s FMA Instruction

#10

> If you apply for a mortgage when your job title is emulation ninja then you are in a quandary. If you write that on the mortgage application then you look like a lunatic. If you write “software engineer” then you get in trouble when the mortgage broker calls your employer. You know. Hypothetically.

Do mortgage brokers call your employer? What’s your mortgage got to do with your employer?

The bank needs to check you're actually employed where you said you are, to make sure you've got a stable income to reliably pay your mortgage. Otherwise you're a huge liability.
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