Re^2: Weird performance issue with Strawberries and Inline::C

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Re^3: Weird performance issue with Strawberries and Inline::C by syphilis (Archbishop) on Oct 13, 2025 at 02:53 UTC
From looking at godbolt gcc 8.3.0 optimizes that branch into the conditional expression while 13.2.0 doesn't Going back through my own builds of perl on Windows, I can see that the rot goes back as far as gcc-10. I don't know if gcc-9 was afflicted with this same issue as I don't have a perl that was built with gcc-9. Incidentally, things are much better with perl-5.42.0 built using Microsoft's Visual Studio 2022: `v5.42.0 String length: 100000 Rate c4 c3 c4 13558/s -- -8% c3 14740/s 9% --` [download] (Well done, them ;-) BTW, the OP will probably be able to use gcc-8.3.0 to build the script, and reap the benefits of the better optimization capabilities provided by gcc-8.3.0. I inserted the following just prior to the "`use Inline C => << 'END_OF_C';`" in the OP's script. `use Inline C => Config => # Force recompilation FORCE_BUILD => 1, # Set CC to to path to gcc.exe version 8.3.0 CC => 'C:/sp/_64/sp-5.32.0/c/bin/gcc.exe', # View build output BUILD_NOISY => 1, ;` [download] That worked fine for me on my build of perl-5.42.0, using gcc-15.1.0: `v5.42.0 String length: 100000 Rate c3 c4 c3 14460/s -- -0% c4 14531/s 0% --` [download] Without that modification, the output was: `v5.42.0 String length: 100000 Rate c4 c3 c4 3528/s -- -76% c3 14777/s 319% --` [download] UPDATE: I tried that same hack of using gcc.exe version 8.3.0 with current blead (built using gcc-15.2.0) and it failed with: `try2_pl_62b5.c: loadable library and perl binaries are mismatched (got + first handshake key 0000000012e00080, needed 0000000012d00080)` [download] ~~Looks like us hackers have now been deprived of yet another liberty.~~ It's a bit more fickle than I thought. The hacked script works fine for my own build of perl-5.42.0, but not for Strawberry's build of perl-5.42.0. (There are small differences between those two builds of 5.42.0, but it would make better sense to me if it was the other way around. Anyway .... whilst I find this to be tantalizingly interesting, it's not massively important.) (If it's going to crash, I would prefer that they let it just do that - rather than forbid something simply because the practice is deemed to be dubious.) Cheers, Rob	[reply] [d/l] [select]
Re^3: Weird performance issue with Strawberries and Inline::C by NERDVANA (Priest) on Oct 13, 2025 at 02:51 UTC
Wow that's a cool website! Never seen that before.	[reply]