ping. On Thu, Nov 16, 2023 at 6:49 PM liuhongt <hongtao....@intel.com> wrote: > > Update in V2: > 1) Add some comments before the pattern. > 2) Remove ? from view_convert. > > Bootstrapped and regtested on x86_64-pc-linux-gnu{-m32,}. > Ok for trunk? > > When I'm working on PR112443, I notice there's some misoptimizations: > after we fold _mm{,256}_blendv_epi8/pd/ps into gimple, the backend > fails to combine it back to v{,p}blendv{v,ps,pd} since the pattern is > too complicated, so I think maybe we should hanlde it in the gimple > level. > > The dump is like > > _1 = c_3(D) >= { 0, 0, 0, 0 }; > _2 = VEC_COND_EXPR <_1, { -1, -1, -1, -1 }, { 0, 0, 0, 0 }>; > _7 = VIEW_CONVERT_EXPR<vector(32) char>(_2); > _8 = VIEW_CONVERT_EXPR<vector(32) char>(b_6(D)); > _9 = VIEW_CONVERT_EXPR<vector(32) char>(a_5(D)); > _10 = _7 < { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, > 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; > _11 = VEC_COND_EXPR <_10, _8, _9>; > > It can be optimized to > > _1 = c_2(D) >= { 0, 0, 0, 0 }; > _6 = VEC_COND_EXPR <_1, b_5(D), a_4(D)>; > > since _7 is either -1 or 0, the selection of _7 < 0 ? _8 : _9 should > be euqal to _1 ? b : a as long as TYPE_PRECISION of the component type > of the second VEC_COND_EXPR is less equal to the first one. > The patch add a gimple pattern to handle that. > > gcc/ChangeLog: > > * match.pd (VCE (a cmp b ? -1 : 0) < 0) ? c : d ---> (VCE ((a > cmp b) ? (VCE:c) : (VCE:d))): New gimple simplication. > > gcc/testsuite/ChangeLog: > > * gcc.target/i386/avx512vl-blendv-3.c: New test. > * gcc.target/i386/blendv-3.c: New test. > --- > gcc/match.pd | 22 +++++++++ > .../gcc.target/i386/avx512vl-blendv-3.c | 6 +++ > gcc/testsuite/gcc.target/i386/blendv-3.c | 46 +++++++++++++++++++ > 3 files changed, 74 insertions(+) > create mode 100644 gcc/testsuite/gcc.target/i386/avx512vl-blendv-3.c > create mode 100644 gcc/testsuite/gcc.target/i386/blendv-3.c > > diff --git a/gcc/match.pd b/gcc/match.pd > index dbc811b2b38..2a69622a300 100644 > --- a/gcc/match.pd > +++ b/gcc/match.pd > @@ -5170,6 +5170,28 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) > (if (optimize_vectors_before_lowering_p () && types_match (@0, @3)) > (vec_cond (bit_and @0 (bit_not @3)) @2 @1))) > > +/* ((VCE (a cmp b ? -1 : 0)) < 0) ? c : d is just > + (VCE ((a cmp b) ? (VCE c) : (VCE d))) when TYPE_PRECISION of the > + component type of the outer vec_cond is greater equal the inner one. */ > +(for cmp (simple_comparison) > + (simplify > + (vec_cond > + (lt (view_convert@5 (vec_cond@6 (cmp@4 @0 @1) > + integer_all_onesp > + integer_zerop)) > + integer_zerop) @2 @3) > + (if (VECTOR_INTEGER_TYPE_P (TREE_TYPE (@0)) > + && VECTOR_INTEGER_TYPE_P (TREE_TYPE (@5)) > + && !TYPE_UNSIGNED (TREE_TYPE (@5)) > + && VECTOR_TYPE_P (TREE_TYPE (@6)) > + && VECTOR_TYPE_P (type) > + && (TYPE_PRECISION (TREE_TYPE (type)) > + <= TYPE_PRECISION (TREE_TYPE (TREE_TYPE (@6)))) > + && TYPE_SIZE (type) == TYPE_SIZE (TREE_TYPE (@6))) > + (with { tree vtype = TREE_TYPE (@6);} > + (view_convert:type > + (vec_cond @4 (view_convert:vtype @2) (view_convert:vtype @3))))))) > + > /* c1 ? c2 ? a : b : b --> (c1 & c2) ? a : b */ > (simplify > (vec_cond @0 (vec_cond:s @1 @2 @3) @3) > diff --git a/gcc/testsuite/gcc.target/i386/avx512vl-blendv-3.c > b/gcc/testsuite/gcc.target/i386/avx512vl-blendv-3.c > new file mode 100644 > index 00000000000..2777e72ab5f > --- /dev/null > +++ b/gcc/testsuite/gcc.target/i386/avx512vl-blendv-3.c > @@ -0,0 +1,6 @@ > +/* { dg-do compile } */ > +/* { dg-options "-mavx512vl -mavx512bw -O2" } */ > +/* { dg-final { scan-assembler-times {vp?blendv(?:b|p[sd])[ \t]*} 6 } } */ > +/* { dg-final { scan-assembler-not {vpcmp} } } */ > + > +#include "blendv-3.c" > diff --git a/gcc/testsuite/gcc.target/i386/blendv-3.c > b/gcc/testsuite/gcc.target/i386/blendv-3.c > new file mode 100644 > index 00000000000..fa0fb067a73 > --- /dev/null > +++ b/gcc/testsuite/gcc.target/i386/blendv-3.c > @@ -0,0 +1,46 @@ > +/* { dg-do compile } */ > +/* { dg-options "-mavx2 -O2" } */ > +/* { dg-final { scan-assembler-times {vp?blendv(?:b|p[sd])[ \t]*} 6 } } */ > +/* { dg-final { scan-assembler-not {vpcmp} } } */ > + > +#include <immintrin.h> > + > +__m256i > +foo (__m256i a, __m256i b, __m256i c) > +{ > + return _mm256_blendv_epi8 (a, b, ~c < 0); > +} > + > +__m256d > +foo1 (__m256d a, __m256d b, __m256i c) > +{ > + __m256i d = ~c < 0; > + return _mm256_blendv_pd (a, b, (__m256d)d); > +} > + > +__m256 > +foo2 (__m256 a, __m256 b, __m256i c) > +{ > + __m256i d = ~c < 0; > + return _mm256_blendv_ps (a, b, (__m256)d); > +} > + > +__m128i > +foo4 (__m128i a, __m128i b, __m128i c) > +{ > + return _mm_blendv_epi8 (a, b, ~c < 0); > +} > + > +__m128d > +foo5 (__m128d a, __m128d b, __m128i c) > +{ > + __m128i d = ~c < 0; > + return _mm_blendv_pd (a, b, (__m128d)d); > +} > + > +__m128 > +foo6 (__m128 a, __m128 b, __m128i c) > +{ > + __m128i d = ~c < 0; > + return _mm_blendv_ps (a, b, (__m128)d); > +} > -- > 2.31.1 >
-- BR, Hongtao