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A comment on How Apple Built a Chip Powerhouse to Threaten Qualcomm and Intel. Parent comment

Re:How Apple Built a Chip Powerhouse to Threaten Qualcomm an... by xenadu02 on Tuesday January 30, 2018 @12:22PM (#16267036)
64-bit ARM has similar advantages as 64-bit x86. It cleans up some cruft but more importantly it doubles the number of registers.
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Re:How Apple Built a Chip Powerhouse to Threaten Qualcomm an... by tooltalk on Tuesday January 30, 2018 @01:30PM (#16267636)
Sure, I get that. What I'm asking is if there were any technical challenges (even to this date) in mobile computing that necessitated a 64-bit mobile chip.
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Re:How Apple Built a Chip Powerhouse to Threaten Qualcomm an... by xenadu02 on Wednesday January 31, 2018 @02:01AM (#16272095)
I guess it depends on your perspective. Is performance a technical challenge? IMHO I say yes.

64-bit enables a number of other things. It has a better ABI for argument passing. It allows more extensive use of tagged pointers (the ObjC runtime can fit many common 11-char or shorter strings in a single tagged pointer). It's also a chance to make any other ABI-breaking changes you want to make in the runtime.

If you're forward looking you might say that mobile devices will exceed the 2GB/4GB limit soon enough so why not make the change now rather than waiting for it to become a problem? You'd get all the performance benefits listed above and a future-proof foundation on which to build.

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