On Mon, Dec 11, 2023 at 7:51 AM liuhongt <hongtao....@intel.com> wrote:
>
> > since you are looking at TYPE_PRECISION below you want
> > VECTOR_INTIEGER_TYPE_P here as well? The alternative
> > would be to compare TYPE_SIZE.
> >
> > Some of the checks feel redundant but are probably good for
> > documentation purposes.
> >
> > OK with using VECTOR_INTIEGER_TYPE_P
> Actually, the data type doens't need to integer, .i.e x86 support vblendvps
> so I'm using TYPE_SIZE here, the code is adjusted to
>
> && tree_fits_uhwi_p (TYPE_SIZE (TREE_TYPE (type)))
> && (tree_to_uhwi (TYPE_SIZE (TREE_TYPE (type)))
> <= TYPE_PRECISION (TREE_TYPE (TREE_TYPE (@6))))
>
> Here's the updated patch.
> 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 | 23 ++++++++++
> .../gcc.target/i386/avx512vl-blendv-3.c | 6 +++
> gcc/testsuite/gcc.target/i386/blendv-3.c | 46 +++++++++++++++++++
> 3 files changed, 75 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 4d554ba4721..359c7b07dc3 100644
> --- a/gcc/match.pd
> +++ b/gcc/match.pd
> @@ -5190,6 +5190,29 @@ 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)
> + && tree_fits_uhwi_p (TYPE_SIZE (TREE_TYPE (type)))
> + && (tree_to_uhwi (TYPE_SIZE (TREE_TYPE (type)))
> + <= TYPE_PRECISION (TREE_TYPE (TREE_TYPE (@6))))
sorry for nitpicking, but can you please use
&& tree_int_cst_le (TYPE_SIZE (TREE_TYPE (type)),
TREE_TYPE (TREE_TYPE (@6)))
thus not use precision on one and size on the other type?
OK with that change.
Richard.
> + && 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
>
