Single Instruction, Multiple Awesome
Swift 2 brings updated support for SIMD (Single Instruction Multiple Data). What exactly does that mean?
Each CPU vendor has their own unique snowflake versionº but the premise is the same: process data in parallel chunks. Each SIMD instruction operates on a group of values organized into what are called "lanes". . . .
A quick recap for those who haven't parsed the release notes yet:
- Enum cases with values can be used as a function; basically the compiler automatically creates a function that accepts parameters matching the case's values and returns that enum case with the values filled in.
- Non-mutating methods of structs, enums, and . . .
As everyone is no doubt aware Swift 2 was announced at WWDC. I'm going to do a series of posts on the changes but for now let's just cover the major points:
- Global and free-standing functions now follow the same parameter label rules as methods. The
#external name syntax is gone.
- Multi-payload enums basically allow . . .
Reabstraction eats the world
This is an update on a previous post.
First, @jckarter pointed out that
swift_func_object is an artifact of the implementation. Swift is reabstracting the function to promote it to the most generic form (it's how a
()->Int can be passed to something expecting
()->Void). It turns out that Swift lifts functions to the maximally . . .
Don't do this. Seriously.
Edit: There are some important developments, please make sure you check them out.. You shouldn't have tried to use this code before but now it's just completely unnecessary.
This is horrible and you should never never do this under any circumstances. There are plenty of bear traps in software engineering. You needn't put . . .
Use this one weird trick
Swift has a variety of little documented (or undocumented) attributes just sitting there waiting to be used. Let's look at a few of them:
This attribute gives the compiler inlining hints. The valid values are
never. I don't think I'd use this one (especially
__always) unless I was absolutely certain I needed . . .
I just wanted to add my name to the list.
At home, I can almost never successfully make AirDrop work between my iOS devices and Mac, or between my wife's Mac and mine. It is so unreliable that I . . .