On Thu, Dec 14, 2023 at 3:54 PM Hongyu Wang <hongyu.w...@intel.com> wrote:
>
> Hi,
>
> Currently move_max follows the tuning feature first, but ideally it
> should sync with prefer-vector-width when it is explicitly set to keep
> vector move and operation with same vector size.
>
> Bootstrapped/regtested on x86-64-pc-linux-gnu{-m32,}
>
> OK for trunk?
>
> gcc/ChangeLog:
>
> PR target/112824
> * config/i386/i386-options.cc (ix86_option_override_internal):
> Sync ix86_move_max/ix86_store_max with prefer_vector_width when
> it is explicitly set.
>
> gcc/testsuite/ChangeLog:
>
> PR target/112824
> * gcc.target/i386/pieces-memset-45.c: Remove
> -mprefer-vector-width=256.
> * g++.target/i386/pr112824-1.C: New test.
> ---
> gcc/config/i386/i386-options.cc | 8 +-
> gcc/testsuite/g++.target/i386/pr112824-1.C | 113 ++++++++++++++++++
> .../gcc.target/i386/pieces-memset-45.c | 2 +-
> 3 files changed, 120 insertions(+), 3 deletions(-)
> create mode 100644 gcc/testsuite/g++.target/i386/pr112824-1.C
>
> diff --git a/gcc/config/i386/i386-options.cc b/gcc/config/i386/i386-options.cc
> index 588a0878c0d..440ef59ffff 100644
> --- a/gcc/config/i386/i386-options.cc
> +++ b/gcc/config/i386/i386-options.cc
> @@ -3012,7 +3012,9 @@ ix86_option_override_internal (bool main_args_p,
> {
> /* Set the maximum number of bits can be moved from memory to
> memory efficiently. */
> - if (ix86_tune_features[X86_TUNE_AVX512_MOVE_BY_PIECES])
> + if (opts_set->x_prefer_vector_width_type != PVW_NONE)
> + opts->x_ix86_move_max = opts->x_prefer_vector_width_type;
> + else if (ix86_tune_features[X86_TUNE_AVX512_MOVE_BY_PIECES])
> opts->x_ix86_move_max = PVW_AVX512;
> else if (ix86_tune_features[X86_TUNE_AVX256_MOVE_BY_PIECES])
> opts->x_ix86_move_max = PVW_AVX256;
> @@ -3034,7 +3036,9 @@ ix86_option_override_internal (bool main_args_p,
> {
> /* Set the maximum number of bits can be stored to memory
> efficiently. */
> - if (ix86_tune_features[X86_TUNE_AVX512_STORE_BY_PIECES])
> + if (opts_set->x_prefer_vector_width_type != PVW_NONE)
> + opts->x_ix86_store_max = opts->x_prefer_vector_width_type;
> + else if (ix86_tune_features[X86_TUNE_AVX512_STORE_BY_PIECES])
> opts->x_ix86_store_max = PVW_AVX512;
> else if (ix86_tune_features[X86_TUNE_AVX256_STORE_BY_PIECES])
> opts->x_ix86_store_max = PVW_AVX256;
> diff --git a/gcc/testsuite/g++.target/i386/pr112824-1.C
> b/gcc/testsuite/g++.target/i386/pr112824-1.C
> new file mode 100644
> index 00000000000..fccaf23c530
> --- /dev/null
> +++ b/gcc/testsuite/g++.target/i386/pr112824-1.C
> @@ -0,0 +1,113 @@
> +/* PR target/112824 */
> +/* { dg-do compile } */
> +/* { dg-options "-std=c++23 -O3 -march=skylake-avx512
> -mprefer-vector-width=512" } */
> +/* { dg-final { scan-assembler-not "vmov(?:dqu|apd)\[ \\t\]+\[^\n\]*%ymm" }
> } */
> +
> +
remove empty line.
> +#include <bit>
> +#include <concepts>
> +#include <cstddef>
> +#include <cstdint>
> +
> +template <ptrdiff_t W, typename T>
> +using Vec [[gnu::vector_size(W * sizeof(T))]] = T;
> +
> +// Omitted: 16 without AVX, 32 without AVX512F,
> +// or for forward compatibility some AVX10 may also mean 32-only
> +static constexpr ptrdiff_t VectorBytes = 64;
> +template<typename T>
> +static constexpr ptrdiff_t VecWidth = 64 <= sizeof(T) ? 1 : 64/sizeof(T);
> +
> +template <typename T, ptrdiff_t N> struct Vector{
> + static constexpr ptrdiff_t L = N;
> + T data[L];
> + static constexpr auto size()->ptrdiff_t{return N;}
> +};
> +template <std::floating_point T, ptrdiff_t N> struct Vector<T,N>{
> + static constexpr ptrdiff_t W = N >= VecWidth<T> ? VecWidth<T> :
> ptrdiff_t(std::bit_ceil(size_t(N)));
> + static constexpr ptrdiff_t L = (N/W) + ((N%W)!=0);
> + using V = Vec<W,T>;
> + V data[L];
> + static constexpr auto size()->ptrdiff_t{return N;}
> +};
> +/// should be trivially copyable
> +/// codegen is worse when passing by value, even though it seems like it
> should make
> +/// aliasing simpler to analyze?
> +template<typename T, ptrdiff_t N>
> +[[gnu::always_inline]] constexpr auto operator+(Vector<T,N> x, Vector<T,N>
> y) -> Vector<T,N> {
> + Vector<T,N> z;
> + for (ptrdiff_t n = 0; n < Vector<T,N>::L; ++n) z.data[n] = x.data[n] +
> y.data[n];
> + return z;
> +}
> +template<typename T, ptrdiff_t N>
> +[[gnu::always_inline]] constexpr auto operator*(Vector<T,N> x, Vector<T,N>
> y) -> Vector<T,N> {
> + Vector<T,N> z;
> + for (ptrdiff_t n = 0; n < Vector<T,N>::L; ++n) z.data[n] = x.data[n] *
> y.data[n];
> + return z;
> +}
> +template<typename T, ptrdiff_t N>
> +[[gnu::always_inline]] constexpr auto operator+(T x, Vector<T,N> y) ->
> Vector<T,N> {
> + Vector<T,N> z;
> + for (ptrdiff_t n = 0; n < Vector<T,N>::L; ++n) z.data[n] = x + y.data[n];
> + return z;
> +}
> +template<typename T, ptrdiff_t N>
> +[[gnu::always_inline]] constexpr auto operator*(T x, Vector<T,N> y) ->
> Vector<T,N> {
> + Vector<T,N> z;
> + for (ptrdiff_t n = 0; n < Vector<T,N>::L; ++n) z.data[n] = x * y.data[n];
> + return z;
> +}
> +
> +
> +
Ditto.
> +template <typename T, ptrdiff_t N> struct Dual {
> + T value;
> + Vector<T, N> partials;
> +};
> +// Here we have a specialization for non-power-of-2 `N`
> +template <typename T, ptrdiff_t N>
> +requires(std::floating_point<T> && (std::popcount(size_t(N))>1))
> +struct Dual<T,N> {
> + Vector<T, N+1> data;
> +};
> +
> +template<ptrdiff_t W, typename T>
> +consteval auto firstoff(){
> + static_assert(std::same_as<T,double>, "type not implemented");
> + if constexpr (W==2) return Vec<2,int64_t>{0,1} != 0;
> + else if constexpr (W == 4) return Vec<4,int64_t>{0,1,2,3} != 0;
> + else if constexpr (W == 8) return Vec<8,int64_t>{0,1,2,3,4,5,6,7} != 0;
> + else static_assert(false, "vector width not implemented");
> +}
> +
> +template <typename T, ptrdiff_t N>
> +[[gnu::always_inline]] constexpr auto operator+(Dual<T, N> a,
> + Dual<T, N> b)
> + -> Dual<T, N> {
> + if constexpr (std::floating_point<T> && (std::popcount(size_t(N))>1)){
> + Dual<T,N> c;
> + for (ptrdiff_t l = 0; l < Vector<T,N>::L; ++l)
> + c.data.data[l] = a.data.data[l] + b.data.data[l];
> + return c;
> + } else return {a.value + b.value, a.partials + b.partials};
> +}
> +
> +template <typename T, ptrdiff_t N>
> +[[gnu::always_inline]] constexpr auto operator*(Dual<T, N> a,
> + Dual<T, N> b)
> + -> Dual<T, N> {
> + if constexpr (std::floating_point<T> && (std::popcount(size_t(N))>1)){
> + using V = typename Vector<T,N>::V;
> + V va = V{}+a.data.data[0][0], vb = V{}+b.data.data[0][0];
> + V x = va * b.data.data[0];
> + Dual<T,N> c;
> + c.data.data[0] = firstoff<Vector<T,N>::W,T>() ? x + vb*a.data.data[0] :
> x;
> + for (ptrdiff_t l = 1; l < Vector<T,N>::L; ++l)
> + c.data.data[l] = va*b.data.data[l] + vb*a.data.data[l];
> + return c;
> + } else return {a.value * b.value, a.value * b.partials + b.value *
> a.partials};
> +}
> +
> +void prod(Dual<Dual<double,7>,2> &c, const Dual<Dual<double,7>,2> &a, const
> Dual<Dual<double,7>,2>&b){
> + c = a*b;
> +}
> diff --git a/gcc/testsuite/gcc.target/i386/pieces-memset-45.c
> b/gcc/testsuite/gcc.target/i386/pieces-memset-45.c
> index 70c80e5064b..e8ce7c23256 100644
> --- a/gcc/testsuite/gcc.target/i386/pieces-memset-45.c
> +++ b/gcc/testsuite/gcc.target/i386/pieces-memset-45.c
> @@ -1,5 +1,5 @@
> /* { dg-do compile } */
> -/* { dg-options "-O2 -march=x86-64 -mprefer-vector-width=256 -mavx512f
> -mtune-ctrl=avx512_store_by_pieces" } */
> +/* { dg-options "-O2 -march=x86-64 -mavx512f
> -mtune-ctrl=avx512_store_by_pieces" } */
>
> extern char *dst;
>
> --
> 2.31.1
>
Others LGTM.
--
BR,
Hongtao
