On Mon, Aug 10, 2026 at 7:12 PM H.J. Lu <[email protected]> wrote: > > On Mon, Aug 10, 2026 at 10:06 AM H.J. Lu <[email protected]> wrote: > > > > On Sun, Aug 9, 2026 at 6:26 PM <[email protected]> wrote: > > > > > > From: Kyrylo Tkachov <[email protected]> > > > > > > The positive test only folds when the wide and narrow vector MIN > > > operations > > > are available. Default x86_64 lowers the V2DI MIN before the narrowing > > > rule > > > can see it, so the dump still contains the wide type. > > > > > > Enable AVX512VL and AVX512DQ for x86 targets to enable the type. > > > > > > Tested on x86_64-pc-linux-gnu. > > > Pushed to trunk. > > > > > > gcc/testsuite/ChangeLog: > > > > > > * g++.dg/tree-ssa/vec-narrow-1.C: Enable AVX512VL and AVX512DQ on > > > x86 targets. > > > > > > Signed-off-by: Kyrylo Tkachov <[email protected]> > > > --- > > > gcc/testsuite/g++.dg/tree-ssa/vec-narrow-1.C | 1 + > > > 1 file changed, 1 insertion(+) > > > > > > diff --git a/gcc/testsuite/g++.dg/tree-ssa/vec-narrow-1.C > > > b/gcc/testsuite/g++.dg/tree-ssa/vec-narrow-1.C > > > index de738e33c30..cec5b0ba345 100644 > > > --- a/gcc/testsuite/g++.dg/tree-ssa/vec-narrow-1.C > > > +++ b/gcc/testsuite/g++.dg/tree-ssa/vec-narrow-1.C > > > @@ -1,5 +1,6 @@ > > > // { dg-do compile } > > > // { dg-options "-O2 -fdump-tree-optimized" } > > > +// { dg-additional-options "-mavx512vl -mavx512dq" { target { i?86-*-* > > > x86_64-*-* } } } > > Also -msse4 is sufficient.
I opened: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126784 > > > // Extension is monotone, so it commutes with the comparison and the > > > outer > > > // truncation is exact. The argument is lanewise, so a widened vector > > > // MIN/MAX feeding a truncating conversion narrows. > > > -- > > > 2.50.1 (Apple Git-155) > > > > > > > This failed with > > > > $ make check-c++ RUNTESTFLAGS="--target_board='unix{-m32}' > > dg.exp=vec-narrow-1.C" > > > > on Linux/x86-64. > > > > -- > > H.J. > > > > -- > H.J. -- H.J.
