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0 pointswillvarfar10y ago0 comments

It means exactly that.

Here's a nice article describing it:

> This means that apps can automatically “take advantage of new processor capabilities we might be adding in the future, without you re-submitting to the store.”

http://thenextweb.com/apple/2015/06/17/apples-biggest-develo...

0 comments

vsl10y ago

It doesn't. Bitcode is arch specific and unportable. It allows some instruction-set level optimizations, but not changing e.g. endianness (exactly what x64 and arm differ in) or type sizes.

willvarfarOP10y ago

ARM cores, although technically bi-endian, are in practice little-endian.

I play writing LLVM backends, and its entirely viable to even do things like rewrite float80 and other assumptions that a front-end has made for a particular target.

jakobegger10y ago

But what about things like non-aligned memory access (allowed on x86, not allowed on ARM)? Porting code across architectures can't be as easy as just swapping LLVM backends, when not even recompiling the code is sufficient.

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