On Tuesday 19 January 2016 09:50:37 Gunnar Roth wrote: > Thank you Thiago. > > Actually I meant ucomparing a QString with a QStringLiteral when i said > " both strings being uft16 seems to be faster ". > So what i learned now on an x85 with avx support is should be no performance > problem.
We also have SSE2 code which should provide similar performance, but not better since the unpacking code is more expensive than the one AVX2 instruction that loads and zero-extends. > But what about a wec2013 with arm, as qt does not support neon for > wec2013. I don't do benchmarks for ARM. That said, Erik and Allan have been re-writing some of my vector code from SSE2 to Neon and are contributing the code to the dev branch. Some of the functionality is possible only in AArch64 due to the lack of one single instruction corresponding to SSE2's PMOVMSKB in 32-bit mode. That includes the string-compare code. > Qt does not even support sse2 for wec because configureap.cpp does > always reset sse2 to no, even if i pass it to configure. Probably because whoever wrote that part of configureapp.cpp assumed that it would always be ARM. > Same as the > openssl problem, which was solved in dev > branch. https://codereview.qt-project.org/#/c/122437/ Right. -- Thiago Macieira - thiago.macieira (AT) intel.com Software Architect - Intel Open Source Technology Center _______________________________________________ Development mailing list [email protected] http://lists.qt-project.org/mailman/listinfo/development
