Re: [swift-dev] Swift incremental compile profiling

Thank you, Jordan! I had guessed there wouldn't be much low-hanging fruit here -- I'm sure a ton of work has been put into improving compilation time, after all. Thanks for all the great explanations. The one thing we *could* do here is improve -driver-show-incremental. I > haven’t used it in a w

Re: [swift-dev] Swift incremental compile profiling

[+swift-dev again, for posterity] Let’s see, those two are really mostly “I haven’t thought about how to recover from this scenario.” I have an internal presentation on why dependency analysis is the way it is that I should probably throw up in the docs in some format, but mostly these are all

Re: [swift-dev] Swift incremental compile profiling

Sorry to resurrect an old thread, but: Jordan, I'm trying to learn more about swift/lib/Driver. I picked up a few tasks to get familiar with it: - https://bugs.swift.org/browse/SR-1788- https://bugs.swift.org/browse/SR-2400- https://bugs.swift.org/browse/SR-656 I didn't find any tasks related to

Re: [swift-dev] Swift incremental compile profiling

> On Apr 25, 2016, at 8:15 PM, Samantha John wrote: > > On Mon, Apr 25, 2016 at 12:11 AM, Daniel Dunbar > wrote: > >> On Apr 24, 2016, at 3:19 PM, Samantha John via swift-dev >> mailto:swift-dev@swift.org>> wrote: >> >> Hello List (cc/Jordan), >> >> At a hi

Re: [swift-dev] Swift incremental compile profiling

On Mon, Apr 25, 2016 at 12:11 AM, Daniel Dunbar wrote: > > On Apr 24, 2016, at 3:19 PM, Samantha John via swift-dev < > swift-dev@swift.org> wrote: > > Hello List (cc/Jordan), > > At a high level: Brian and I are looking into contributing to incremental > compilation in Swift. Right now we're try

Re: [swift-dev] Swift incremental compile profiling

> On Apr 24, 2016, at 3:19 PM, Samantha John via swift-dev > wrote: > > Hello List (cc/Jordan), > > At a high level: Brian and I are looking into contributing to incremental > compilation in Swift. Right now we're trying to do an incremental compile by > invoking swiftc. > > Our understa

Re: [swift-dev] Swift incremental compile profiling

Hello List (cc/Jordan), At a high level: Brian and I are looking into contributing to incremental compilation in Swift. Right now we're trying to do an incremental compile by invoking swiftc. Our understanding so far: - swiftc takes a list of input files. - If swiftc is invoked with '-incremental

Re: [swift-dev] Swift incremental compile profiling

Hi Jordan, The thing that sticks out in the dependency analysis is the treatment of external dependencies. The entire module has the same list of external dependencies which causes a lot of needless recompiles- especially if you start with a large swift project and slowly start to move things into

Re: [swift-dev] Swift incremental compile profiling

Hey Sam, One thought: if you have an app with mixed objc and swift code, then the app-bridge.h and app-swift.h files might be creating massive choke points in your dependency graph. I have no idea how optimized the bridging functionality is but it has always seemed like a potentially weak part

Re: [swift-dev] Swift incremental compile profiling

Thank you Jordan! This is a great starting off point. I'm thinking about proposing a "strict import" mode in swift: A compile flag that when turned on would require you to explicitly import any file that contained a dependency you needed (like in objective-c). I'm going to spend more time looking

Re: [swift-dev] Swift incremental compile profiling

Hi, Sam. I don't think we currently have a good answer for this built into xcodebuild or xctool, and it's a reasonable idea. (Ideally all builds would be fast enough that it wouldn't matter! That's obviously not where we are.) Since '-debug-time-function-bodies' is now public knowledge, I'll sha

[swift-dev] Swift incremental compile profiling

I have a large project (308 swift files, 441 objective c, 66k lines of code) where incremental builds can be extremely slow. I'm trying to do some profiling to figure out what type of things cause large scale recompiles. The problem is that I can't find a good way of telling which files get recompi