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A comment on On Apple Announcing the ARM Mac Transition at WWDC This Month.

Re:On Apple Announcing the ARM Mac Transition at WWDC This M... by jasonhansel on Tuesday June 09, 2020 @06:20PM (#23471598)
Why not just require apps to be distributed as LLVM bitcode, as is done for the Apple watch? That would give Apple the flexibility to change architectures--or even to create its own instruction set, now that it's making its own chips.
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Re:On Apple Announcing the ARM Mac Transition at WWDC This M... by p_l on Tuesday June 09, 2020 @06:43PM (#23471783)
LLVM bitcode is not that portable in reality. Just like Plan9 assembly intermediary bitcode files are pretty much single architecture, due to containing lots and lots of low-level assumptions about the target architecture, not to mention possible incompatibilities in extended intrinsics (for example for vector units).
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Re:On Apple Announcing the ARM Mac Transition at WWDC This M... by Scaevolus on Tuesday June 09, 2020 @07:27PM (#23472132)
Most of the portability problems for retargetting to another little endian 64-bit architecture aren't the easy ones of bit widths and integer types, but rather more subtle things like a more relaxed memory model and different performance characteristics.

It's not worth the overhead of attempting to ship bitcode. Apple has shipped products on 6502, 68000, PPC, x86, x86-64, ARM, and ARM64. The transitions have been annoying for the lost software, but that's not an unusual occurrence for an OSX upgrade either.

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Re:On Apple Announcing the ARM Mac Transition at WWDC This M... by philistine on Tuesday June 09, 2020 @07:33PM (#23472173)
What was the Newton using ?
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Re:On Apple Announcing the ARM Mac Transition at WWDC This M... by portlander52232 on Tuesday June 09, 2020 @07:52PM (#23472318)
They were also ARM.
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