a221f1c36d
These don't return reliable portable results, so I don't want to promote them as good ideas to use. You can get at least 5 different results from these across the four main architectures we support, and they've been the root cause of bugs uncovered only in production on undertested platforms. Luckily, unused outside of tests. Change-Id: I532731fe4cddf127253341e5ace8d9c5c9ebb0f1 Reviewed-on: https://skia-review.googlesource.com/c/skia/+/326108 Reviewed-by: Herb Derby <herb@google.com> Commit-Queue: Mike Klein <mtklein@google.com>
681 lines
29 KiB
C++
681 lines
29 KiB
C++
/*
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* Copyright 2019 Google Inc.
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*
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* Use of this source code is governed by a BSD-style license that can be
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* found in the LICENSE file.
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*/
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#ifndef SKVX_DEFINED
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#define SKVX_DEFINED
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// skvx::Vec<N,T> are SIMD vectors of N T's, a v1.5 successor to SkNx<N,T>.
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//
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// This time we're leaning a bit less on platform-specific intrinsics and a bit
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// more on Clang/GCC vector extensions, but still keeping the option open to
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// drop in platform-specific intrinsics, actually more easily than before.
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//
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// We've also fixed a few of the caveats that used to make SkNx awkward to work
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// with across translation units. skvx::Vec<N,T> always has N*sizeof(T) size
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// and alignment and is safe to use across translation units freely.
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// (Ideally we'd only align to T, but that tanks ARMv7 NEON codegen.)
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// Please try to keep this file independent of Skia headers.
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#include <algorithm> // std::min, std::max
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#include <cmath> // ceilf, floorf, truncf, roundf, sqrtf, etc.
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#include <cstdint> // intXX_t
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#include <cstring> // memcpy()
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#include <initializer_list> // std::initializer_list
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#include <utility> // std::index_sequence
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#if defined(__SSE__) || defined(__AVX__) || defined(__AVX2__)
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#include <immintrin.h>
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#elif defined(__ARM_NEON)
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#include <arm_neon.h>
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#elif defined(__wasm_simd128__)
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#include <wasm_simd128.h>
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#endif
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// To avoid ODR violations, all methods must be force-inlined...
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#if defined(_MSC_VER)
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#define SKVX_ALWAYS_INLINE __forceinline
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#else
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#define SKVX_ALWAYS_INLINE __attribute__((always_inline))
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#endif
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// ... and all standalone functions must be static. Please use these helpers:
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#define SI static inline
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#define SIT template < typename T> SI
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#define SIN template <int N > SI
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#define SINT template <int N, typename T> SI
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#define SINTU template <int N, typename T, typename U, \
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typename=std::enable_if_t<std::is_convertible<U,T>::value>> SI
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namespace skvx {
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// All Vec have the same simple memory layout, the same as `T vec[N]`.
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template <int N, typename T>
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struct alignas(N*sizeof(T)) Vec {
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static_assert((N & (N-1)) == 0, "N must be a power of 2.");
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static_assert(sizeof(T) >= alignof(T), "What kind of crazy T is this?");
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Vec<N/2,T> lo, hi;
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// Methods belong here in the class declaration of Vec only if:
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// - they must be here, like constructors or operator[];
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// - they'll definitely never want a specialized implementation.
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// Other operations on Vec should be defined outside the type.
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SKVX_ALWAYS_INLINE Vec() = default;
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template <typename U, typename=std::enable_if_t<std::is_convertible<U,T>::value>>
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SKVX_ALWAYS_INLINE
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Vec(U x) : lo(x), hi(x) {}
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SKVX_ALWAYS_INLINE Vec(std::initializer_list<T> xs) {
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T vals[N] = {0};
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memcpy(vals, xs.begin(), std::min(xs.size(), (size_t)N)*sizeof(T));
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lo = Vec<N/2,T>::Load(vals + 0);
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hi = Vec<N/2,T>::Load(vals + N/2);
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}
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SKVX_ALWAYS_INLINE T operator[](int i) const { return i < N/2 ? lo[i] : hi[i-N/2]; }
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SKVX_ALWAYS_INLINE T& operator[](int i) { return i < N/2 ? lo[i] : hi[i-N/2]; }
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SKVX_ALWAYS_INLINE static Vec Load(const void* ptr) {
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Vec v;
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memcpy(&v, ptr, sizeof(Vec));
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return v;
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}
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SKVX_ALWAYS_INLINE void store(void* ptr) const {
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memcpy(ptr, this, sizeof(Vec));
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}
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};
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template <typename T>
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struct Vec<1,T> {
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T val;
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SKVX_ALWAYS_INLINE Vec() = default;
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template <typename U, typename=std::enable_if_t<std::is_convertible<U,T>::value>>
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SKVX_ALWAYS_INLINE
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Vec(U x) : val(x) {}
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SKVX_ALWAYS_INLINE Vec(std::initializer_list<T> xs) : val(xs.size() ? *xs.begin() : 0) {}
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SKVX_ALWAYS_INLINE T operator[](int) const { return val; }
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SKVX_ALWAYS_INLINE T& operator[](int) { return val; }
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SKVX_ALWAYS_INLINE static Vec Load(const void* ptr) {
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Vec v;
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memcpy(&v, ptr, sizeof(Vec));
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return v;
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}
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SKVX_ALWAYS_INLINE void store(void* ptr) const {
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memcpy(ptr, this, sizeof(Vec));
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}
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};
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// Ideally we'd only use bit_pun(), but until this file is always built as C++17 with constexpr if,
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// we'll sometimes find need to use unchecked_bit_pun(). Please do check the call sites yourself!
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template <typename D, typename S>
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SI D unchecked_bit_pun(const S& s) {
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D d;
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memcpy(&d, &s, sizeof(D));
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return d;
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}
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template <typename D, typename S>
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SI D bit_pun(const S& s) {
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static_assert(sizeof(D) == sizeof(S), "");
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return unchecked_bit_pun<D>(s);
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}
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// Translate from a value type T to its corresponding Mask, the result of a comparison.
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template <typename T> struct Mask { using type = T; };
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template <> struct Mask<float > { using type = int32_t; };
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template <> struct Mask<double> { using type = int64_t; };
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template <typename T> using M = typename Mask<T>::type;
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// Join two Vec<N,T> into one Vec<2N,T>.
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SINT Vec<2*N,T> join(const Vec<N,T>& lo, const Vec<N,T>& hi) {
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Vec<2*N,T> v;
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v.lo = lo;
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v.hi = hi;
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return v;
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}
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// We have three strategies for implementing Vec operations:
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// 1) lean on Clang/GCC vector extensions when available;
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// 2) use map() to apply a scalar function lane-wise;
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// 3) recurse on lo/hi to scalar portable implementations.
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// We can slot in platform-specific implementations as overloads for particular Vec<N,T>,
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// or often integrate them directly into the recursion of style 3), allowing fine control.
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#if !defined(SKNX_NO_SIMD) && (defined(__clang__) || defined(__GNUC__))
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// VExt<N,T> types have the same size as Vec<N,T> and support most operations directly.
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#if defined(__clang__)
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template <int N, typename T>
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using VExt = T __attribute__((ext_vector_type(N)));
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#elif defined(__GNUC__)
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template <int N, typename T>
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struct VExtHelper {
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typedef T __attribute__((vector_size(N*sizeof(T)))) type;
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};
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template <int N, typename T>
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using VExt = typename VExtHelper<N,T>::type;
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// For some reason some (new!) versions of GCC cannot seem to deduce N in the generic
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// to_vec<N,T>() below for N=4 and T=float. This workaround seems to help...
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SI Vec<4,float> to_vec(VExt<4,float> v) { return bit_pun<Vec<4,float>>(v); }
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#endif
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SINT VExt<N,T> to_vext(const Vec<N,T>& v) { return bit_pun<VExt<N,T>>(v); }
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SINT Vec <N,T> to_vec(const VExt<N,T>& v) { return bit_pun<Vec <N,T>>(v); }
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SINT Vec<N,T> operator+(const Vec<N,T>& x, const Vec<N,T>& y) {
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return to_vec<N,T>(to_vext(x) + to_vext(y));
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}
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SINT Vec<N,T> operator-(const Vec<N,T>& x, const Vec<N,T>& y) {
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return to_vec<N,T>(to_vext(x) - to_vext(y));
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}
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SINT Vec<N,T> operator*(const Vec<N,T>& x, const Vec<N,T>& y) {
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return to_vec<N,T>(to_vext(x) * to_vext(y));
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}
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SINT Vec<N,T> operator/(const Vec<N,T>& x, const Vec<N,T>& y) {
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return to_vec<N,T>(to_vext(x) / to_vext(y));
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}
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SINT Vec<N,T> operator^(const Vec<N,T>& x, const Vec<N,T>& y) {
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return to_vec<N,T>(to_vext(x) ^ to_vext(y));
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}
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SINT Vec<N,T> operator&(const Vec<N,T>& x, const Vec<N,T>& y) {
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return to_vec<N,T>(to_vext(x) & to_vext(y));
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}
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SINT Vec<N,T> operator|(const Vec<N,T>& x, const Vec<N,T>& y) {
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return to_vec<N,T>(to_vext(x) | to_vext(y));
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}
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SINT Vec<N,T> operator!(const Vec<N,T>& x) { return to_vec<N,T>(!to_vext(x)); }
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SINT Vec<N,T> operator-(const Vec<N,T>& x) { return to_vec<N,T>(-to_vext(x)); }
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SINT Vec<N,T> operator~(const Vec<N,T>& x) { return to_vec<N,T>(~to_vext(x)); }
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SINT Vec<N,T> operator<<(const Vec<N,T>& x, int k) { return to_vec<N,T>(to_vext(x) << k); }
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SINT Vec<N,T> operator>>(const Vec<N,T>& x, int k) { return to_vec<N,T>(to_vext(x) >> k); }
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SINT Vec<N,M<T>> operator==(const Vec<N,T>& x, const Vec<N,T>& y) {
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return bit_pun<Vec<N,M<T>>>(to_vext(x) == to_vext(y));
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}
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SINT Vec<N,M<T>> operator!=(const Vec<N,T>& x, const Vec<N,T>& y) {
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return bit_pun<Vec<N,M<T>>>(to_vext(x) != to_vext(y));
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}
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SINT Vec<N,M<T>> operator<=(const Vec<N,T>& x, const Vec<N,T>& y) {
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return bit_pun<Vec<N,M<T>>>(to_vext(x) <= to_vext(y));
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}
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SINT Vec<N,M<T>> operator>=(const Vec<N,T>& x, const Vec<N,T>& y) {
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return bit_pun<Vec<N,M<T>>>(to_vext(x) >= to_vext(y));
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}
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SINT Vec<N,M<T>> operator< (const Vec<N,T>& x, const Vec<N,T>& y) {
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return bit_pun<Vec<N,M<T>>>(to_vext(x) < to_vext(y));
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}
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SINT Vec<N,M<T>> operator> (const Vec<N,T>& x, const Vec<N,T>& y) {
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return bit_pun<Vec<N,M<T>>>(to_vext(x) > to_vext(y));
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}
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#else
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// Either SKNX_NO_SIMD is defined, or Clang/GCC vector extensions are not available.
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// We'll implement things portably with N==1 scalar implementations and recursion onto them.
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// N == 1 scalar implementations.
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SIT Vec<1,T> operator+(const Vec<1,T>& x, const Vec<1,T>& y) { return x.val + y.val; }
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SIT Vec<1,T> operator-(const Vec<1,T>& x, const Vec<1,T>& y) { return x.val - y.val; }
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SIT Vec<1,T> operator*(const Vec<1,T>& x, const Vec<1,T>& y) { return x.val * y.val; }
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SIT Vec<1,T> operator/(const Vec<1,T>& x, const Vec<1,T>& y) { return x.val / y.val; }
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SIT Vec<1,T> operator^(const Vec<1,T>& x, const Vec<1,T>& y) { return x.val ^ y.val; }
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SIT Vec<1,T> operator&(const Vec<1,T>& x, const Vec<1,T>& y) { return x.val & y.val; }
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SIT Vec<1,T> operator|(const Vec<1,T>& x, const Vec<1,T>& y) { return x.val | y.val; }
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SIT Vec<1,T> operator!(const Vec<1,T>& x) { return !x.val; }
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SIT Vec<1,T> operator-(const Vec<1,T>& x) { return -x.val; }
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SIT Vec<1,T> operator~(const Vec<1,T>& x) { return ~x.val; }
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SIT Vec<1,T> operator<<(const Vec<1,T>& x, int k) { return x.val << k; }
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SIT Vec<1,T> operator>>(const Vec<1,T>& x, int k) { return x.val >> k; }
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SIT Vec<1,M<T>> operator==(const Vec<1,T>& x, const Vec<1,T>& y) {
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return x.val == y.val ? ~0 : 0;
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}
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SIT Vec<1,M<T>> operator!=(const Vec<1,T>& x, const Vec<1,T>& y) {
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return x.val != y.val ? ~0 : 0;
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}
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SIT Vec<1,M<T>> operator<=(const Vec<1,T>& x, const Vec<1,T>& y) {
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return x.val <= y.val ? ~0 : 0;
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}
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SIT Vec<1,M<T>> operator>=(const Vec<1,T>& x, const Vec<1,T>& y) {
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return x.val >= y.val ? ~0 : 0;
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}
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SIT Vec<1,M<T>> operator< (const Vec<1,T>& x, const Vec<1,T>& y) {
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return x.val < y.val ? ~0 : 0;
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}
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SIT Vec<1,M<T>> operator> (const Vec<1,T>& x, const Vec<1,T>& y) {
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return x.val > y.val ? ~0 : 0;
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}
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// Recurse on lo/hi down to N==1 scalar implementations.
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SINT Vec<N,T> operator+(const Vec<N,T>& x, const Vec<N,T>& y) {
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return join(x.lo + y.lo, x.hi + y.hi);
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}
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SINT Vec<N,T> operator-(const Vec<N,T>& x, const Vec<N,T>& y) {
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return join(x.lo - y.lo, x.hi - y.hi);
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}
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SINT Vec<N,T> operator*(const Vec<N,T>& x, const Vec<N,T>& y) {
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return join(x.lo * y.lo, x.hi * y.hi);
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}
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SINT Vec<N,T> operator/(const Vec<N,T>& x, const Vec<N,T>& y) {
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return join(x.lo / y.lo, x.hi / y.hi);
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}
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SINT Vec<N,T> operator^(const Vec<N,T>& x, const Vec<N,T>& y) {
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return join(x.lo ^ y.lo, x.hi ^ y.hi);
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}
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SINT Vec<N,T> operator&(const Vec<N,T>& x, const Vec<N,T>& y) {
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return join(x.lo & y.lo, x.hi & y.hi);
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}
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SINT Vec<N,T> operator|(const Vec<N,T>& x, const Vec<N,T>& y) {
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return join(x.lo | y.lo, x.hi | y.hi);
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}
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SINT Vec<N,T> operator!(const Vec<N,T>& x) { return join(!x.lo, !x.hi); }
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SINT Vec<N,T> operator-(const Vec<N,T>& x) { return join(-x.lo, -x.hi); }
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SINT Vec<N,T> operator~(const Vec<N,T>& x) { return join(~x.lo, ~x.hi); }
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SINT Vec<N,T> operator<<(const Vec<N,T>& x, int k) { return join(x.lo << k, x.hi << k); }
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SINT Vec<N,T> operator>>(const Vec<N,T>& x, int k) { return join(x.lo >> k, x.hi >> k); }
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SINT Vec<N,M<T>> operator==(const Vec<N,T>& x, const Vec<N,T>& y) {
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return join(x.lo == y.lo, x.hi == y.hi);
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}
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SINT Vec<N,M<T>> operator!=(const Vec<N,T>& x, const Vec<N,T>& y) {
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return join(x.lo != y.lo, x.hi != y.hi);
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}
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SINT Vec<N,M<T>> operator<=(const Vec<N,T>& x, const Vec<N,T>& y) {
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return join(x.lo <= y.lo, x.hi <= y.hi);
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}
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SINT Vec<N,M<T>> operator>=(const Vec<N,T>& x, const Vec<N,T>& y) {
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return join(x.lo >= y.lo, x.hi >= y.hi);
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}
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SINT Vec<N,M<T>> operator< (const Vec<N,T>& x, const Vec<N,T>& y) {
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return join(x.lo < y.lo, x.hi < y.hi);
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}
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SINT Vec<N,M<T>> operator> (const Vec<N,T>& x, const Vec<N,T>& y) {
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return join(x.lo > y.lo, x.hi > y.hi);
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}
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#endif
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// Scalar/vector operations splat the scalar to a vector.
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SINTU Vec<N,T> operator+ (U x, const Vec<N,T>& y) { return Vec<N,T>(x) + y; }
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SINTU Vec<N,T> operator- (U x, const Vec<N,T>& y) { return Vec<N,T>(x) - y; }
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SINTU Vec<N,T> operator* (U x, const Vec<N,T>& y) { return Vec<N,T>(x) * y; }
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SINTU Vec<N,T> operator/ (U x, const Vec<N,T>& y) { return Vec<N,T>(x) / y; }
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SINTU Vec<N,T> operator^ (U x, const Vec<N,T>& y) { return Vec<N,T>(x) ^ y; }
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SINTU Vec<N,T> operator& (U x, const Vec<N,T>& y) { return Vec<N,T>(x) & y; }
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SINTU Vec<N,T> operator| (U x, const Vec<N,T>& y) { return Vec<N,T>(x) | y; }
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SINTU Vec<N,M<T>> operator==(U x, const Vec<N,T>& y) { return Vec<N,T>(x) == y; }
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SINTU Vec<N,M<T>> operator!=(U x, const Vec<N,T>& y) { return Vec<N,T>(x) != y; }
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SINTU Vec<N,M<T>> operator<=(U x, const Vec<N,T>& y) { return Vec<N,T>(x) <= y; }
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SINTU Vec<N,M<T>> operator>=(U x, const Vec<N,T>& y) { return Vec<N,T>(x) >= y; }
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SINTU Vec<N,M<T>> operator< (U x, const Vec<N,T>& y) { return Vec<N,T>(x) < y; }
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SINTU Vec<N,M<T>> operator> (U x, const Vec<N,T>& y) { return Vec<N,T>(x) > y; }
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SINTU Vec<N,T> operator+ (const Vec<N,T>& x, U y) { return x + Vec<N,T>(y); }
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SINTU Vec<N,T> operator- (const Vec<N,T>& x, U y) { return x - Vec<N,T>(y); }
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SINTU Vec<N,T> operator* (const Vec<N,T>& x, U y) { return x * Vec<N,T>(y); }
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SINTU Vec<N,T> operator/ (const Vec<N,T>& x, U y) { return x / Vec<N,T>(y); }
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SINTU Vec<N,T> operator^ (const Vec<N,T>& x, U y) { return x ^ Vec<N,T>(y); }
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SINTU Vec<N,T> operator& (const Vec<N,T>& x, U y) { return x & Vec<N,T>(y); }
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SINTU Vec<N,T> operator| (const Vec<N,T>& x, U y) { return x | Vec<N,T>(y); }
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SINTU Vec<N,M<T>> operator==(const Vec<N,T>& x, U y) { return x == Vec<N,T>(y); }
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SINTU Vec<N,M<T>> operator!=(const Vec<N,T>& x, U y) { return x != Vec<N,T>(y); }
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SINTU Vec<N,M<T>> operator<=(const Vec<N,T>& x, U y) { return x <= Vec<N,T>(y); }
|
|
SINTU Vec<N,M<T>> operator>=(const Vec<N,T>& x, U y) { return x >= Vec<N,T>(y); }
|
|
SINTU Vec<N,M<T>> operator< (const Vec<N,T>& x, U y) { return x < Vec<N,T>(y); }
|
|
SINTU Vec<N,M<T>> operator> (const Vec<N,T>& x, U y) { return x > Vec<N,T>(y); }
|
|
|
|
SINT Vec<N,T>& operator+=(Vec<N,T>& x, const Vec<N,T>& y) { return (x = x + y); }
|
|
SINT Vec<N,T>& operator-=(Vec<N,T>& x, const Vec<N,T>& y) { return (x = x - y); }
|
|
SINT Vec<N,T>& operator*=(Vec<N,T>& x, const Vec<N,T>& y) { return (x = x * y); }
|
|
SINT Vec<N,T>& operator/=(Vec<N,T>& x, const Vec<N,T>& y) { return (x = x / y); }
|
|
SINT Vec<N,T>& operator^=(Vec<N,T>& x, const Vec<N,T>& y) { return (x = x ^ y); }
|
|
SINT Vec<N,T>& operator&=(Vec<N,T>& x, const Vec<N,T>& y) { return (x = x & y); }
|
|
SINT Vec<N,T>& operator|=(Vec<N,T>& x, const Vec<N,T>& y) { return (x = x | y); }
|
|
|
|
SINTU Vec<N,T>& operator+=(Vec<N,T>& x, U y) { return (x = x + Vec<N,T>(y)); }
|
|
SINTU Vec<N,T>& operator-=(Vec<N,T>& x, U y) { return (x = x - Vec<N,T>(y)); }
|
|
SINTU Vec<N,T>& operator*=(Vec<N,T>& x, U y) { return (x = x * Vec<N,T>(y)); }
|
|
SINTU Vec<N,T>& operator/=(Vec<N,T>& x, U y) { return (x = x / Vec<N,T>(y)); }
|
|
SINTU Vec<N,T>& operator^=(Vec<N,T>& x, U y) { return (x = x ^ Vec<N,T>(y)); }
|
|
SINTU Vec<N,T>& operator&=(Vec<N,T>& x, U y) { return (x = x & Vec<N,T>(y)); }
|
|
SINTU Vec<N,T>& operator|=(Vec<N,T>& x, U y) { return (x = x | Vec<N,T>(y)); }
|
|
|
|
SINT Vec<N,T>& operator<<=(Vec<N,T>& x, int bits) { return (x = x << bits); }
|
|
SINT Vec<N,T>& operator>>=(Vec<N,T>& x, int bits) { return (x = x >> bits); }
|
|
|
|
// Some operations we want are not expressible with Clang/GCC vector extensions.
|
|
|
|
// Clang can reason about naive_if_then_else() and optimize through it better
|
|
// than if_then_else(), so it's sometimes useful to call it directly when we
|
|
// think an entire expression should optimize away, e.g. min()/max().
|
|
SINT Vec<N,T> naive_if_then_else(const Vec<N,M<T>>& cond, const Vec<N,T>& t, const Vec<N,T>& e) {
|
|
return bit_pun<Vec<N,T>>(( cond & bit_pun<Vec<N, M<T>>>(t)) |
|
|
(~cond & bit_pun<Vec<N, M<T>>>(e)) );
|
|
}
|
|
|
|
SIT Vec<1,T> if_then_else(const Vec<1,M<T>>& cond, const Vec<1,T>& t, const Vec<1,T>& e) {
|
|
// In practice this scalar implementation is unlikely to be used. See next if_then_else().
|
|
return bit_pun<Vec<1,T>>(( cond & bit_pun<Vec<1, M<T>>>(t)) |
|
|
(~cond & bit_pun<Vec<1, M<T>>>(e)) );
|
|
}
|
|
SINT Vec<N,T> if_then_else(const Vec<N,M<T>>& cond, const Vec<N,T>& t, const Vec<N,T>& e) {
|
|
// Specializations inline here so they can generalize what types the apply to.
|
|
// (This header is used in C++14 contexts, so we have to kind of fake constexpr if.)
|
|
#if defined(__AVX2__)
|
|
if /*constexpr*/ (N*sizeof(T) == 32) {
|
|
return unchecked_bit_pun<Vec<N,T>>(_mm256_blendv_epi8(unchecked_bit_pun<__m256i>(e),
|
|
unchecked_bit_pun<__m256i>(t),
|
|
unchecked_bit_pun<__m256i>(cond)));
|
|
}
|
|
#endif
|
|
#if defined(__SSE4_1__)
|
|
if /*constexpr*/ (N*sizeof(T) == 16) {
|
|
return unchecked_bit_pun<Vec<N,T>>(_mm_blendv_epi8(unchecked_bit_pun<__m128i>(e),
|
|
unchecked_bit_pun<__m128i>(t),
|
|
unchecked_bit_pun<__m128i>(cond)));
|
|
}
|
|
#endif
|
|
#if defined(__ARM_NEON)
|
|
if /*constexpr*/ (N*sizeof(T) == 16) {
|
|
return unchecked_bit_pun<Vec<N,T>>(vbslq_u8(unchecked_bit_pun<uint8x16_t>(cond),
|
|
unchecked_bit_pun<uint8x16_t>(t),
|
|
unchecked_bit_pun<uint8x16_t>(e)));
|
|
}
|
|
#endif
|
|
// Recurse for large vectors to try to hit the specializations above.
|
|
if /*constexpr*/ (N*sizeof(T) > 16) {
|
|
return join(if_then_else(cond.lo, t.lo, e.lo),
|
|
if_then_else(cond.hi, t.hi, e.hi));
|
|
}
|
|
// This default can lead to better code than the recursing onto scalars.
|
|
return naive_if_then_else(cond, t, e);
|
|
}
|
|
|
|
SIT bool any(const Vec<1,T>& x) { return x.val != 0; }
|
|
SINT bool any(const Vec<N,T>& x) {
|
|
#if defined(__wasm_simd128__)
|
|
if constexpr (N == 4 && sizeof(T) == 4) {
|
|
return wasm_i32x4_any_true(unchecked_bit_pun<VExt<4,int>>(x));
|
|
}
|
|
#endif
|
|
return any(x.lo)
|
|
|| any(x.hi);
|
|
}
|
|
|
|
SIT bool all(const Vec<1,T>& x) { return x.val != 0; }
|
|
SINT bool all(const Vec<N,T>& x) {
|
|
#if defined(__AVX2__)
|
|
if /*constexpr*/ (N*sizeof(T) == 32) {
|
|
return _mm256_testc_si256(unchecked_bit_pun<__m256i>(x),
|
|
_mm256_set1_epi32(-1));
|
|
}
|
|
#endif
|
|
#if defined(__SSE4_1__)
|
|
if /*constexpr*/ (N*sizeof(T) == 16) {
|
|
return _mm_testc_si128(unchecked_bit_pun<__m128i>(x),
|
|
_mm_set1_epi32(-1));
|
|
}
|
|
#endif
|
|
#if defined(__wasm_simd128__)
|
|
if /*constexpr*/ (N == 4 && sizeof(T) == 4) {
|
|
return wasm_i32x4_all_true(unchecked_bit_pun<VExt<4,int>>(x));
|
|
}
|
|
#endif
|
|
return all(x.lo)
|
|
&& all(x.hi);
|
|
}
|
|
|
|
// cast() Vec<N,S> to Vec<N,D>, as if applying a C-cast to each lane.
|
|
// TODO: implement with map()?
|
|
template <typename D, typename S>
|
|
SI Vec<1,D> cast(const Vec<1,S>& src) { return (D)src.val; }
|
|
|
|
template <typename D, int N, typename S>
|
|
SI Vec<N,D> cast(const Vec<N,S>& src) {
|
|
#if !defined(SKNX_NO_SIMD) && defined(__clang__)
|
|
return to_vec(__builtin_convertvector(to_vext(src), VExt<N,D>));
|
|
#else
|
|
return join(cast<D>(src.lo), cast<D>(src.hi));
|
|
#endif
|
|
}
|
|
|
|
// min/max match logic of std::min/std::max, which is important when NaN is involved.
|
|
SIT T min(const Vec<1,T>& x) { return x.val; }
|
|
SIT T max(const Vec<1,T>& x) { return x.val; }
|
|
SINT T min(const Vec<N,T>& x) { return std::min(min(x.lo), min(x.hi)); }
|
|
SINT T max(const Vec<N,T>& x) { return std::max(max(x.lo), max(x.hi)); }
|
|
|
|
SINT Vec<N,T> min(const Vec<N,T>& x, const Vec<N,T>& y) { return naive_if_then_else(y < x, y, x); }
|
|
SINT Vec<N,T> max(const Vec<N,T>& x, const Vec<N,T>& y) { return naive_if_then_else(x < y, y, x); }
|
|
|
|
SINTU Vec<N,T> min(const Vec<N,T>& x, U y) { return min(x, Vec<N,T>(y)); }
|
|
SINTU Vec<N,T> max(const Vec<N,T>& x, U y) { return max(x, Vec<N,T>(y)); }
|
|
SINTU Vec<N,T> min(U x, const Vec<N,T>& y) { return min(Vec<N,T>(x), y); }
|
|
SINTU Vec<N,T> max(U x, const Vec<N,T>& y) { return max(Vec<N,T>(x), y); }
|
|
|
|
|
|
// Shuffle values from a vector pretty arbitrarily:
|
|
// skvx::Vec<4,float> rgba = {R,G,B,A};
|
|
// shuffle<2,1,0,3> (rgba) ~> {B,G,R,A}
|
|
// shuffle<2,1> (rgba) ~> {B,G}
|
|
// shuffle<2,1,2,1,2,1,2,1>(rgba) ~> {B,G,B,G,B,G,B,G}
|
|
// shuffle<3,3,3,3> (rgba) ~> {A,A,A,A}
|
|
// The only real restriction is that the output also be a legal N=power-of-two sknx::Vec.
|
|
template <int... Ix, int N, typename T>
|
|
SI Vec<sizeof...(Ix),T> shuffle(const Vec<N,T>& x) {
|
|
#if !defined(SKNX_NO_SIMD) && defined(__clang__)
|
|
// TODO: can we just always use { x[Ix]... }?
|
|
return to_vec<sizeof...(Ix),T>(__builtin_shufflevector(to_vext(x), to_vext(x), Ix...));
|
|
#else
|
|
return { x[Ix]... };
|
|
#endif
|
|
}
|
|
|
|
// Call map(fn, x) for a vector with fn() applied to each lane of x, { fn(x[0]), fn(x[1]), ... },
|
|
// or map(fn, x,y) for a vector of fn(x[i], y[i]), etc.
|
|
|
|
template <typename Fn, typename... Args, size_t... I>
|
|
#if defined(__clang__)
|
|
// CFI, specifically -fsanitize=cfi-icall, seems to give a false positive here,
|
|
// with errors like "control flow integrity check for type 'float (float)
|
|
// noexcept' failed during indirect function call... note: sqrtf.cfi_jt defined
|
|
// here". But we can be quite sure fn is the right type: it's all inferred!
|
|
// So, stifle CFI in this function.
|
|
__attribute__((no_sanitize("cfi")))
|
|
#endif
|
|
SI auto map(std::index_sequence<I...>,
|
|
Fn&& fn, const Args&... args) -> skvx::Vec<sizeof...(I), decltype(fn(args[0]...))> {
|
|
auto lane = [&](size_t i) { return fn(args[i]...); };
|
|
return { lane(I)... };
|
|
}
|
|
|
|
template <typename Fn, int N, typename T, typename... Rest>
|
|
auto map(Fn&& fn, const Vec<N,T>& first, const Rest&... rest) {
|
|
// Derive an {0...N-1} index_sequence from the size of the first arg: N lanes in, N lanes out.
|
|
return map(std::make_index_sequence<N>{}, fn, first,rest...);
|
|
}
|
|
|
|
// TODO: remove functions that are unlikely to ever vectorize (atan, sin, cos, tan, pow)?
|
|
|
|
SIN Vec<N,float> atan(const Vec<N,float>& x) { return map( atanf, x); }
|
|
SIN Vec<N,float> ceil(const Vec<N,float>& x) { return map( ceilf, x); }
|
|
SIN Vec<N,float> floor(const Vec<N,float>& x) { return map(floorf, x); }
|
|
SIN Vec<N,float> trunc(const Vec<N,float>& x) { return map(truncf, x); }
|
|
SIN Vec<N,float> round(const Vec<N,float>& x) { return map(roundf, x); }
|
|
SIN Vec<N,float> sqrt(const Vec<N,float>& x) { return map( sqrtf, x); }
|
|
SIN Vec<N,float> abs(const Vec<N,float>& x) { return map( fabsf, x); }
|
|
SIN Vec<N,float> sin(const Vec<N,float>& x) { return map( sinf, x); }
|
|
SIN Vec<N,float> cos(const Vec<N,float>& x) { return map( cosf, x); }
|
|
SIN Vec<N,float> tan(const Vec<N,float>& x) { return map( tanf, x); }
|
|
SIN Vec<N,float> pow(const Vec<N,float>& x,
|
|
const Vec<N,float>& y) { return map(powf, x,y); }
|
|
SIN Vec<N,float> fma(const Vec<N,float>& x,
|
|
const Vec<N,float>& y,
|
|
const Vec<N,float>& z) {
|
|
// I don't understand why Clang's codegen is terrible if we write map(fmaf, x,y,z) directly.
|
|
auto fn = [](float x, float y, float z) { return fmaf(x,y,z); };
|
|
return map(fn, x,y,z);
|
|
}
|
|
|
|
SI Vec<1,int> lrint(const Vec<1,float>& x) {
|
|
return (int)lrintf(x.val);
|
|
}
|
|
SIN Vec<N,int> lrint(const Vec<N,float>& x) {
|
|
#if defined(__AVX__)
|
|
if /*constexpr*/ (N == 8) {
|
|
return unchecked_bit_pun<Vec<N,int>>(_mm256_cvtps_epi32(unchecked_bit_pun<__m256>(x)));
|
|
}
|
|
#endif
|
|
#if defined(__SSE__)
|
|
if /*constexpr*/ (N == 4) {
|
|
return unchecked_bit_pun<Vec<N,int>>(_mm_cvtps_epi32(unchecked_bit_pun<__m128>(x)));
|
|
}
|
|
#endif
|
|
return join(lrint(x.lo),
|
|
lrint(x.hi));
|
|
}
|
|
|
|
SIN Vec<N,float> fract(const Vec<N,float>& x) { return x - floor(x); }
|
|
|
|
// The default logic for to_half/from_half is borrowed from skcms,
|
|
// and assumes inputs are finite and treat/flush denorm half floats as/to zero.
|
|
// Key constants to watch for:
|
|
// - a float is 32-bit, 1-8-23 sign-exponent-mantissa, with 127 exponent bias;
|
|
// - a half is 16-bit, 1-5-10 sign-exponent-mantissa, with 15 exponent bias.
|
|
SIN Vec<N,uint16_t> to_half_finite_ftz(const Vec<N,float>& x) {
|
|
Vec<N,uint32_t> sem = bit_pun<Vec<N,uint32_t>>(x),
|
|
s = sem & 0x8000'0000,
|
|
em = sem ^ s,
|
|
is_denorm = em < 0x3880'0000;
|
|
return cast<uint16_t>(if_then_else(is_denorm, Vec<N,uint32_t>(0)
|
|
, (s>>16) + (em>>13) - ((127-15)<<10)));
|
|
}
|
|
SIN Vec<N,float> from_half_finite_ftz(const Vec<N,uint16_t>& x) {
|
|
Vec<N,uint32_t> wide = cast<uint32_t>(x),
|
|
s = wide & 0x8000,
|
|
em = wide ^ s;
|
|
auto is_denorm = bit_pun<Vec<N,int32_t>>(em < 0x0400);
|
|
return if_then_else(is_denorm, Vec<N,float>(0)
|
|
, bit_pun<Vec<N,float>>( (s<<16) + (em<<13) + ((127-15)<<23) ));
|
|
}
|
|
|
|
// Like if_then_else(), these N=1 base cases won't actually be used unless explicitly called.
|
|
SI Vec<1,uint16_t> to_half(const Vec<1,float>& x) { return to_half_finite_ftz(x); }
|
|
SI Vec<1,float> from_half(const Vec<1,uint16_t>& x) { return from_half_finite_ftz(x); }
|
|
|
|
SIN Vec<N,uint16_t> to_half(const Vec<N,float>& x) {
|
|
#if defined(__F16C__)
|
|
if /*constexpr*/ (N == 8) {
|
|
return unchecked_bit_pun<Vec<N,uint16_t>>(_mm256_cvtps_ph(unchecked_bit_pun<__m256>(x),
|
|
_MM_FROUND_CUR_DIRECTION));
|
|
}
|
|
#endif
|
|
#if defined(__aarch64__)
|
|
if /*constexpr*/ (N == 4) {
|
|
return unchecked_bit_pun<Vec<N,uint16_t>>(vcvt_f16_f32(unchecked_bit_pun<float32x4_t>(x)));
|
|
|
|
}
|
|
#endif
|
|
if /*constexpr*/ (N > 4) {
|
|
return join(to_half(x.lo),
|
|
to_half(x.hi));
|
|
}
|
|
return to_half_finite_ftz(x);
|
|
}
|
|
|
|
SIN Vec<N,float> from_half(const Vec<N,uint16_t>& x) {
|
|
#if defined(__F16C__)
|
|
if /*constexpr*/ (N == 8) {
|
|
return unchecked_bit_pun<Vec<N,float>>(_mm256_cvtph_ps(unchecked_bit_pun<__m128i>(x)));
|
|
}
|
|
#endif
|
|
#if defined(__aarch64__)
|
|
if /*constexpr*/ (N == 4) {
|
|
return unchecked_bit_pun<Vec<N,float>>(vcvt_f32_f16(unchecked_bit_pun<float16x4_t>(x)));
|
|
}
|
|
#endif
|
|
if /*constexpr*/ (N > 4) {
|
|
return join(from_half(x.lo),
|
|
from_half(x.hi));
|
|
}
|
|
return from_half_finite_ftz(x);
|
|
}
|
|
|
|
|
|
// div255(x) = (x + 127) / 255 is a bit-exact rounding divide-by-255, packing down to 8-bit.
|
|
SIN Vec<N,uint8_t> div255(const Vec<N,uint16_t>& x) {
|
|
return cast<uint8_t>( (x+127)/255 );
|
|
}
|
|
|
|
// approx_scale(x,y) approximates div255(cast<uint16_t>(x)*cast<uint16_t>(y)) within a bit,
|
|
// and is always perfect when x or y is 0 or 255.
|
|
SIN Vec<N,uint8_t> approx_scale(const Vec<N,uint8_t>& x, const Vec<N,uint8_t>& y) {
|
|
// All of (x*y+x)/256, (x*y+y)/256, and (x*y+255)/256 meet the criteria above.
|
|
// We happen to have historically picked (x*y+x)/256.
|
|
auto X = cast<uint16_t>(x),
|
|
Y = cast<uint16_t>(y);
|
|
return cast<uint8_t>( (X*Y+X)/256 );
|
|
}
|
|
|
|
#if !defined(SKNX_NO_SIMD) && defined(__ARM_NEON)
|
|
// With NEON we can do eight u8*u8 -> u16 in one instruction, vmull_u8 (read, mul-long).
|
|
SI Vec<8,uint16_t> mull(const Vec<8,uint8_t>& x,
|
|
const Vec<8,uint8_t>& y) {
|
|
return to_vec<8,uint16_t>(vmull_u8(to_vext(x),
|
|
to_vext(y)));
|
|
}
|
|
|
|
SIN std::enable_if_t<(N < 8), Vec<N,uint16_t>> mull(const Vec<N,uint8_t>& x,
|
|
const Vec<N,uint8_t>& y) {
|
|
// N < 8 --> double up data until N == 8, returning the part we need.
|
|
return mull(join(x,x),
|
|
join(y,y)).lo;
|
|
}
|
|
|
|
SIN std::enable_if_t<(N > 8), Vec<N,uint16_t>> mull(const Vec<N,uint8_t>& x,
|
|
const Vec<N,uint8_t>& y) {
|
|
// N > 8 --> usual join(lo,hi) strategy to recurse down to N == 8.
|
|
return join(mull(x.lo, y.lo),
|
|
mull(x.hi, y.hi));
|
|
}
|
|
#else
|
|
// Nothing special when we don't have NEON... just cast up to 16-bit and multiply.
|
|
SIN Vec<N,uint16_t> mull(const Vec<N,uint8_t>& x,
|
|
const Vec<N,uint8_t>& y) {
|
|
return cast<uint16_t>(x)
|
|
* cast<uint16_t>(y);
|
|
}
|
|
#endif
|
|
|
|
} // namespace skvx
|
|
|
|
#undef SINTU
|
|
#undef SINT
|
|
#undef SIT
|
|
#undef SI
|
|
|
|
#endif//SKVX_DEFINED
|