libxslt @1.1.34_6: add a variant for better performance

[cooljeanius (Eric Gallager)]

The xsltproc binary can be very slow sometimes; to deal with that, I would like a variant of libxslt that turns on additional optimization options for increased performance. An example variant can be found in my copy of the libxslt Portfile in my LocalPorts repo: ​https://github.com/cooljeanius/LocalPorts/blob/6f35e07e73b6aebbf1074fee8b25717b5c4ce3b0/textproc/libxslt/Portfile#L86-L89

[szhorvat (Szabolcs Horvát)]

I would like to second this request, and suggest also turning on link-time optimization when supported. At the moment this is one of the annoying bottlenecks for a project I am working on, and any improvements would be most welcome.

[szhorvat (Szabolcs Horvát)]

I benchmarked my own use case after adding -O3 -flto=thin. The timing went from 104 to 96 seconds. That's a 7-8% improvement, not small, but also not huge for my own usecase.

The above suggestion includes many additional optimization options that are unsafe, and I would not be comfortable using. I did not include the patch.

I tried this with the default compiler on macOS 10.14.6.

[szhorvat (Szabolcs Horvát)]

libxslt was just updated to 1.1.37 in MacPorts. This version performs much better with the default options (85 seconds with the same benchmark). With this version, using -O3 -flto=thin makes no significant different in performance.

Unless others see a significant effect from optimization options, this issue can be closed.

[ryandesign (Ryan Carsten Schmidt)]

Ok thanks for letting us know.

[dgilman (David Gilman)]

In 7058a97e88289743eccc2ad551aaaf85c1b7e2ae/macports-ports (master):

libxslt: update to 1.1.38

Closes: #46724
Closes: #63601