Re: [Interest] Qt Application - Disabling AVX/AVX2
Kind regards, Robert Iakobashvili On Wed, Apr 22, 2020 at 6:40 PM coroberti . wrote: > > On Wed, Apr 22, 2020 at 6:35 PM Allan Sandfeld Jensen > wrote: > > > > On Mittwoch, 22. April 2020 17:29:56 CEST coroberti . wrote: > > > On Wed, Apr 22, 2020 at 6:17 PM Thiago Macieira > > > > > > wrote: > > > > On Tuesday, 21 April 2020 14:26:13 PDT coroberti . wrote: > > > > > Hi, > > > > > Is it enough to define: > > > > > > > > > > QMAKE_CFLAGS -= -arch:AVX -arch:AVX2 > > > > > QMAKE_CXXFLAGS -= -arch:AVX -arch:AVX2 > > > > > > > > > > to ensure that compilation by QtCreator with Qt-5.14-MSVC Windows > > > > > will not compile with such optimization flags even if avx and avx2 > > > > > instructions have not been disabled in Qt-library itself? > > > > > > > > Since those options aren't added to the CFLAGS or CXXFLAGS in the first > > > > place, by default what you're tryng to do is a no-op. > > > > Why do you think there are AVX instructions in your binary? And how did > > > > you > > > > turn them on in the first place? > > > > Thiago Macieira - thiago.macieira (AT) intel.com > > > > > > > > Software Architect - Intel System Software Products > > > > > > Thank you for your reply. > > > > > > Building 5.14.2, I was alerted by report from config that avx > > > instructions are enabled. > > > > > > Clear, I need to investigate it more. > > > > > Probably support for them is enabled, but not turned on. That is what we do > > in > > qtbase, build only some files with AVX enabled and switch to them on at > > runtime. > > > > 'Allan > > > Thanks, Allan. > > Perhaps, like Microsoft, AVX optimized functions will be used only if > runtime support by CPU detected. > > Kind regards, > Robert I've seen it. It's not just a good job, it's a fantastically great job done in qtbase. It even navigates thru the mess of compiler versions/issues. Thanks, Thiago and Allan! Kind regards, Robert ___ Interest mailing list Interest@qt-project.org https://lists.qt-project.org/listinfo/interest
Re: [Interest] Qt Application - Disabling AVX/AVX2
On Wed, Apr 22, 2020 at 6:35 PM Allan Sandfeld Jensen wrote: > > On Mittwoch, 22. April 2020 17:29:56 CEST coroberti . wrote: > > On Wed, Apr 22, 2020 at 6:17 PM Thiago Macieira > > > > wrote: > > > On Tuesday, 21 April 2020 14:26:13 PDT coroberti . wrote: > > > > Hi, > > > > Is it enough to define: > > > > > > > > QMAKE_CFLAGS -= -arch:AVX -arch:AVX2 > > > > QMAKE_CXXFLAGS -= -arch:AVX -arch:AVX2 > > > > > > > > to ensure that compilation by QtCreator with Qt-5.14-MSVC Windows > > > > will not compile with such optimization flags even if avx and avx2 > > > > instructions have not been disabled in Qt-library itself? > > > > > > Since those options aren't added to the CFLAGS or CXXFLAGS in the first > > > place, by default what you're tryng to do is a no-op. > > > Why do you think there are AVX instructions in your binary? And how did > > > you > > > turn them on in the first place? > > > Thiago Macieira - thiago.macieira (AT) intel.com > > > > > > Software Architect - Intel System Software Products > > > > Thank you for your reply. > > > > Building 5.14.2, I was alerted by report from config that avx > > instructions are enabled. > > > > Clear, I need to investigate it more. > > > Probably support for them is enabled, but not turned on. That is what we do in > qtbase, build only some files with AVX enabled and switch to them on at > runtime. > > 'Allan > Thanks, Allan. Perhaps, like Microsoft, AVX optimized functions will be used only if runtime support by CPU detected. Kind regards, Robert ___ Interest mailing list Interest@qt-project.org https://lists.qt-project.org/listinfo/interest
Re: [Interest] Qt Application - Disabling AVX/AVX2
On Mittwoch, 22. April 2020 17:29:56 CEST coroberti . wrote: > On Wed, Apr 22, 2020 at 6:17 PM Thiago Macieira > > wrote: > > On Tuesday, 21 April 2020 14:26:13 PDT coroberti . wrote: > > > Hi, > > > Is it enough to define: > > > > > > QMAKE_CFLAGS -= -arch:AVX -arch:AVX2 > > > QMAKE_CXXFLAGS -= -arch:AVX -arch:AVX2 > > > > > > to ensure that compilation by QtCreator with Qt-5.14-MSVC Windows > > > will not compile with such optimization flags even if avx and avx2 > > > instructions have not been disabled in Qt-library itself? > > > > Since those options aren't added to the CFLAGS or CXXFLAGS in the first > > place, by default what you're tryng to do is a no-op. > > Why do you think there are AVX instructions in your binary? And how did > > you > > turn them on in the first place? > > Thiago Macieira - thiago.macieira (AT) intel.com > > > > Software Architect - Intel System Software Products > > Thank you for your reply. > > Building 5.14.2, I was alerted by report from config that avx > instructions are enabled. > > Clear, I need to investigate it more. > Probably support for them is enabled, but not turned on. That is what we do in qtbase, build only some files with AVX enabled and switch to them on at runtime. 'Allan ___ Interest mailing list Interest@qt-project.org https://lists.qt-project.org/listinfo/interest
Re: [Interest] Qt Application - Disabling AVX/AVX2
On Wed, Apr 22, 2020 at 6:17 PM Thiago Macieira wrote: > > On Tuesday, 21 April 2020 14:26:13 PDT coroberti . wrote: > > Hi, > > Is it enough to define: > > > > QMAKE_CFLAGS -= -arch:AVX -arch:AVX2 > > QMAKE_CXXFLAGS -= -arch:AVX -arch:AVX2 > > > > to ensure that compilation by QtCreator with Qt-5.14-MSVC Windows > > will not compile with such optimization flags even if avx and avx2 > > instructions have not been disabled in Qt-library itself? > Since those options aren't added to the CFLAGS or CXXFLAGS in the first place, > by default what you're tryng to do is a no-op. > Why do you think there are AVX instructions in your binary? And how did you > turn them on in the first place? > Thiago Macieira - thiago.macieira (AT) intel.com > Software Architect - Intel System Software Products Thank you for your reply. Building 5.14.2, I was alerted by report from config that avx instructions are enabled. Clear, I need to investigate it more. Thanks, Robert ___ Interest mailing list Interest@qt-project.org https://lists.qt-project.org/listinfo/interest
Re: [Interest] Qt Application - Disabling AVX/AVX2
On Tuesday, 21 April 2020 14:26:13 PDT coroberti . wrote: > Hi, > Is it enough to define: > > QMAKE_CFLAGS -= -arch:AVX -arch:AVX2 > QMAKE_CXXFLAGS -= -arch:AVX -arch:AVX2 > > to ensure that compilation by QtCreator with Qt-5.14-MSVC Windows > will not compile with such optimization flags even if avx and avx2 > instructions have not been disabled in Qt-library itself? Since those options aren't added to the CFLAGS or CXXFLAGS in the first place, by default what you're tryng to do is a no-op. Why do you think there are AVX instructions in your binary? And how did you turn them on in the first place? -- Thiago Macieira - thiago.macieira (AT) intel.com Software Architect - Intel System Software Products ___ Interest mailing list Interest@qt-project.org https://lists.qt-project.org/listinfo/interest
[Interest] Qt Application - Disabling AVX/AVX2
Hi, Is it enough to define: QMAKE_CFLAGS -= -arch:AVX -arch:AVX2 QMAKE_CXXFLAGS -= -arch:AVX -arch:AVX2 to ensure that compilation by QtCreator with Qt-5.14-MSVC Windows will not compile with such optimization flags even if avx and avx2 instructions have not been disabled in Qt-library itself? Thanks! Kind regards, Robert ___ Interest mailing list Interest@qt-project.org https://lists.qt-project.org/listinfo/interest