[llvm-dev] TableGen -time-regions option

[Paul C. Anagnostopoulos via llvm-dev]

Ah, I spoke too soon. Let me investigate how the new feature works with Instruments and then I will enhance it if necessary.

At 11/13/2020 10:52 PM, Daniel Sanders wrote:
>Hi Paul,
>
>I'm rather late to the thread but I added the existing -time-regions option when I was debugging a particularly nasty perf problem in TableGen. I really only use it when we have a perf problem downstream.
>
>The main thing I was getting out of it was the ability to annotate periods of time in Xcode Instruments just by adding a NamedRegionTimer to the right function/block (see https://reviews.llvm.org/rGe1414d176048c1f24fc3f54bb923fb48a2b985a3). That helped me track down the work that was taking the time and let me filter out the noise from elsewhere so I could look at the relevant memory allocations+churn. Feel free to change it but I'd like to keep that Instruments integration if we can as I'm sure we'll hit another perf problem sooner or later.