News for hackers. Stuff that matters.
Re:Apple Plans to Use Its Own Chips in Macs from 2020, Repla... by kevin_thibedeau on Monday April 02, 2018 @02:47PM (#16737851)
Creatives who want hardware optimized Adobe apps to continue to be fast will care. I wouldn't count on emulation of vectorized code to work all that well.
Re:Apple Plans to Use Its Own Chips in Macs from 2020, Repla... by flomo on Monday April 02, 2018 @02:54PM (#16737950)
Yep, I think people tend to gloss over how smooth these transitions really were. From a creative professional perspective, they were huge short-term PITA until Adobe etc had everything ported over. Also Excel lost VBA support for several years.
Re:Apple Plans to Use Its Own Chips in Macs from 2020, Repla... by whatok on Monday April 02, 2018 @03:30PM (#16738333)
I remember everything audio was a mess although I'd imagine a lot of it had to do with smaller developers lacking resources to port existing software.
Re:Apple Plans to Use Its Own Chips in Macs from 2020, Repla... by emodendroket on Monday April 02, 2018 @04:08PM (#16738756)
Losing VBA support stinks, but do any professional Excel users even consider Office for Mac?
Re:Apple Plans to Use Its Own Chips in Macs from 2020, Repla... by flomo on Tuesday April 03, 2018 @04:27AM (#16742807)
At least for me "professional Excel users" sent out stuff that I could not open, and that is not good for the for the platform.

"Spreadsheet macros" were like hot personal computing shit in 1983. Really not good if you cannot create them in 2008. , (Few complaints about the current Mac MS Office, FWIW) I'm just saying that breaking old stuff often takes year to fix.

Re:Apple Plans to Use Its Own Chips in Macs from 2020, Repla... by emodendroket on Tuesday April 03, 2018 @12:11PM (#16746117)
No, I get it. I just think that, in general, people who spend a big chunk of most of their work days using Excel kind of consider anything other than Windows MS Office Excel a non-starter.
Re:Apple Plans to Use Its Own Chips in Macs from 2020, Repla... by Eric_WVGG on Monday April 02, 2018 @04:42PM (#16739074)
Adobe's transition was somewhat rough because they took the Carbon route, and then had to do it again to switch over to Cocoa. I expect that now that all their apps are built on Cocoa, the transition will be relatively breezy.
Re:Apple Plans to Use Its Own Chips in Macs from 2020, Repla... by throwaway2048 on Monday April 02, 2018 @05:34PM (#16739595)
emulating x86 on ARM with any kind of real preformanceis additionally tricky because the x86 archetechure has very strong memory gaurentees (dosent matter if memory is aligned, dosent matter when in the instruction pipeline you access it, etc) that ARM isnt even close to matching.

Emulating that requires a massive performance hit, because you essentially have to check every single memory access to make sure its not doing something invalid on ARM.

Re:Apple Plans to Use Its Own Chips in Macs from 2020, Repla... by zlynx on Monday April 02, 2018 @08:15PM (#16740714)
From what I've heard, x86 to PPC or ARM emulators are doing dynamic recompiling and instrumentation. It catches the illegal memory accesses and rebuilds the code responsible to add paths with slower code with alignment compensation.

A lot of x86 code is aligned for speed already so it's a pretty safe bet to assume alignment and fix it up if wrong.

Re:Apple Plans to Use Its Own Chips in Macs from 2020, Repla... by Someone on Monday April 02, 2018 @06:42PM (#16740142)
…or you design your own ARM CPU that handles unaligned memory accesses fine, and run your emulator on that hardware.
Re:Apple Plans to Use Its Own Chips in Macs from 2020, Repla... by readittwice on Tuesday April 03, 2018 @09:29AM (#16744398)
AFAIK the ARM license doesn't allow to invent arbitrary extensions to the ISA. So this might not be allowed.
Re:Apple Plans to Use Its Own Chips in Macs from 2020, Repla... by Someone on Tuesday April 03, 2018 @12:34PM (#16746369)
Apple has an architectural license. I would expect that allows them to add instructions (assuming modern ARM still has the concept of instruction set extensions)

Google didn’t answer that for me, but I found out that there now is a ”cp15 sctlr[1] (alignment bit)”. http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.... says this about it:

”3.5.1. Alignment faults

If alignment fault checking is enabled (the A bit in CP15 c1 is set), the MMU generates an alignment fault on any data word access if the address is not word-aligned, or on any halfword access if the address is not halfword-aligned, irrespective of whether the MMU is enabled or not. An alignment fault is not generated on any instruction fetch or any byte access.”