If I were AMD, I'd just start calling my processor GenuineIntel. (Or maybe make it user programmable, and then absolve myself of any knowledge of what users are setting it to.) When the judge asks why, I'd say because those are the magic words to make certain binaries run faster, and I wanted to run a viable processor business.
But if you were Intel, would you have your engineers work on competitors' products to make sure they are well supported on your line of tools? Before making an answer, consider that the core implementation of AMD cpus differ significanrly from those of Intel: instruction timings are slightly different, whether you look at them individually or in groups. It's not just a matter of turning a switch to get optimal performances, and that's just the tip of the iceberg.
Now, from a business standpoint, I think it could make sense for them to make their compiler produce fast code for any chip, but the legal implications of having a conccurent's product burn because of code produced with your compiler might make you think twice before going that road. Intel probably chose the safe road for a reason. Also, note that the produced code isn't crippled (as in, it doesn't make AMD cpu execute endless loops, or produce wrong results more than Intel's ones), it just follow the safest path.
Add another flag to the compiler to produce code optimized code for any CPU with the warning that it's only been verified to work with Intel CPUs. With todays CPU I do not buy the "safest path" argument - perhaps I could accept that "we only default enable it for implementations we have verified in-house", which makes a lot of sense.
This sounds a lot more like Intel know they make the best compiler, and knowingly put non Intel CPUs at a disadvantage because it would seem that they have a faster CPU.
I guess they could do that, and trust that customers will always be reasonable to not sue them when in those situtations that they wanted to avoid. Besides, it's not 2009 anymore: if they want to maintain their arch on the market against ARM founders, they should probably help AMD out as much as possible (though I remember reading somewhere once that AMD considered including ARM cores in their APUs - or maybe it was just a journalist's speculation).
> This sounds a lot more like Intel [...]
Just a thought here: should Intel do things to avoid sounding like bad competitors, or to give their customers the best product they can offer? We're engineers, we should also know not to fall for appearances, shouldn't we? I know, I supported my own reasoning with the legal aspect of things, which sometimes is not very reasonable in what it must handle. There goes my original point.
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