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// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
// SPDX-FileCopyrightText: The Eigen Authors
// SPDX-License-Identifier: MPL-2.0
// Device-side packet math: test/packetmath.cpp never runs on a GPU. Thread i applies one operation to packet i
// (gpu_common.h's run_on_gpu); the host compares against a reference using bit-exact results, full-bit masks, or a
// named ULP budget. Parts: 1/3 float4/double2 core, 2/4 float4/double2 math, 5/6 half core/math, 7 scalar fallbacks
// and preinterpret.
#define EIGEN_TEST_NO_LONGDOUBLE
#define EIGEN_TEST_NO_COMPLEX
#define EIGEN_USE_GPU
// packetmath_test_shared.h brings in main.h, which has no include guard.
#include "packetmath_test_shared.h"
#include "gpu_common.h"
#include "packetmath_data_movement.h"
#include <algorithm>
#include <cmath>
#include <string>
#include <vector>
// Packet4h2 is an alias of ulonglong2, which exists in both passes but has unpacket_traits only in the device pass:
// eight halves in four half2 lanes.
namespace Eigen {
namespace test {
template <>
struct packet_layout<ulonglong2> {
using Scalar = half;
static constexpr int kSize = 8;
};
} // namespace test
} // namespace Eigen
namespace {
using Eigen::Index;
using Eigen::internal::packet_traits;
namespace test = Eigen::test;
using Eigen::numext::bit_cast;
using test::special_values;
using test::Buffer;
using test::packet_layout;
// Named budgets. rsqrt is the one approximate intrinsic among the core operations: the CUDA Math API documents
// 2 ulp for rsqrtf and 1 ulp for rsqrt. The float reference rounds 1/sqrt from double. The double reference uses
// long double, which is double itself under MSVC; rounding y = sqrt(x) and then 1/y is still within 1.5 ulp of
// 1/sqrt(x), so a device result within 1 ulp is at most 2 representable steps from the reference.
const uint64_t kRsqrtFloatUlps = 3;
const uint64_t kRsqrtDoubleUlps = 2;
// The CUDA Math API's documented maximum error for each function, plus one for the rounding of the reference from
// the wider type. Everything here is a named budget the test pins, so a toolkit regression is a test failure.
struct MathUlpBudget {
uint64_t log, log1p, exp, exp2, expm1;
};
const MathUlpBudget kFloatUlps = {2, 2, 3, 3, 2};
const MathUlpBudget kDoubleUlps = {2, 2, 2, 2, 2};
// The reference is computed one type wider and rounded once.
template <typename Scalar>
struct wider_type {
using type = double;
};
template <>
struct wider_type<double> {
using type = long double;
};
// nvcc compiles sqrtf to a correctly rounded sqrt (-prec-sqrt=true is its default); clang as the CUDA compiler
// lowers it to an approximation one ulp off, and only the __fsqrt_rn intrinsic is exact there. Double sqrt is
// correctly rounded under both.
#if EIGEN_COMP_NVCC
const uint64_t kSqrtFloatUlps = 0;
#else
const uint64_t kSqrtFloatUlps = 1;
#endif
// ------------------------------------------------------------------------------------------------------------------
// Operations: a static run() per packet type, with device-only bodies (EIGEN_PACKET_TEST_FUNC).
#define EIGEN_GPU_TEST_UNARY_OP(NAME, EXPR) \
struct NAME { \
static const char* name() { return #NAME; } \
template <typename P> \
EIGEN_PACKET_TEST_FUNC static P run(const P& a) { \
return EXPR; \
} \
};
#define EIGEN_GPU_TEST_BINARY_OP(NAME, EXPR) \
struct NAME { \
static const char* name() { return #NAME; } \
template <typename P> \
EIGEN_PACKET_TEST_FUNC static P run(const P& a, const P& b) { \
return EXPR; \
} \
};
#define EIGEN_GPU_TEST_TERNARY_OP(NAME, EXPR) \
struct NAME { \
static const char* name() { return #NAME; } \
template <typename P> \
EIGEN_PACKET_TEST_FUNC static P run(const P& a, const P& b, const P& c) { \
return EXPR; \
} \
};
#define EIGEN_GPU_TEST_REDUX_OP(NAME, EXPR) \
struct NAME { \
static const char* name() { return #NAME; } \
template <typename P> \
EIGEN_PACKET_TEST_FUNC static typename packet_layout<P>::Scalar run(const P& a) { \
return EXPR; \
} \
};
EIGEN_GPU_TEST_UNARY_OP(op_identity, a)
EIGEN_GPU_TEST_UNARY_OP(op_pnegate, Eigen::internal::pnegate(a))
EIGEN_GPU_TEST_UNARY_OP(op_pconj, Eigen::internal::pconj(a))
EIGEN_GPU_TEST_UNARY_OP(op_pabs, Eigen::internal::pabs(a))
EIGEN_GPU_TEST_UNARY_OP(op_pfloor, Eigen::internal::pfloor(a))
EIGEN_GPU_TEST_UNARY_OP(op_pceil, Eigen::internal::pceil(a))
EIGEN_GPU_TEST_UNARY_OP(op_print, Eigen::internal::print(a))
EIGEN_GPU_TEST_UNARY_OP(op_ptrunc, Eigen::internal::ptrunc(a))
EIGEN_GPU_TEST_UNARY_OP(op_pround, Eigen::internal::pround(a))
EIGEN_GPU_TEST_UNARY_OP(op_psqrt, Eigen::internal::psqrt(a))
EIGEN_GPU_TEST_UNARY_OP(op_prsqrt, Eigen::internal::prsqrt(a))
EIGEN_GPU_TEST_UNARY_OP(op_plog, Eigen::internal::plog(a))
EIGEN_GPU_TEST_UNARY_OP(op_plog1p, Eigen::internal::plog1p(a))
EIGEN_GPU_TEST_UNARY_OP(op_pexp, Eigen::internal::pexp(a))
EIGEN_GPU_TEST_UNARY_OP(op_pexp2, Eigen::internal::pexp2(a))
EIGEN_GPU_TEST_UNARY_OP(op_pexpm1, Eigen::internal::pexpm1(a))
EIGEN_GPU_TEST_UNARY_OP(op_ptrue, Eigen::internal::ptrue(a))
EIGEN_GPU_TEST_UNARY_OP(op_pzero, Eigen::internal::pzero(a))
EIGEN_GPU_TEST_UNARY_OP(op_preinterpret_self, Eigen::internal::preinterpret<P>(a))
EIGEN_GPU_TEST_UNARY_OP(op_psign, Eigen::internal::psign(a))
EIGEN_GPU_TEST_BINARY_OP(op_padd, Eigen::internal::padd(a, b))
EIGEN_GPU_TEST_BINARY_OP(op_psub, Eigen::internal::psub(a, b))
EIGEN_GPU_TEST_BINARY_OP(op_pmul, Eigen::internal::pmul(a, b))
EIGEN_GPU_TEST_BINARY_OP(op_pdiv, Eigen::internal::pdiv(a, b))
EIGEN_GPU_TEST_BINARY_OP(op_pmin, Eigen::internal::pmin(a, b))
EIGEN_GPU_TEST_BINARY_OP(op_pmax, Eigen::internal::pmax(a, b))
EIGEN_GPU_TEST_BINARY_OP(op_pmin_numbers, Eigen::internal::pmin<Eigen::PropagateNumbers>(a, b))
EIGEN_GPU_TEST_BINARY_OP(op_pmax_numbers, Eigen::internal::pmax<Eigen::PropagateNumbers>(a, b))
EIGEN_GPU_TEST_BINARY_OP(op_pmin_nan, Eigen::internal::pmin<Eigen::PropagateNaN>(a, b))
EIGEN_GPU_TEST_BINARY_OP(op_pmax_nan, Eigen::internal::pmax<Eigen::PropagateNaN>(a, b))
EIGEN_GPU_TEST_BINARY_OP(op_pand, Eigen::internal::pand(a, b))
EIGEN_GPU_TEST_BINARY_OP(op_por, Eigen::internal::por(a, b))
EIGEN_GPU_TEST_BINARY_OP(op_pxor, Eigen::internal::pxor(a, b))
EIGEN_GPU_TEST_BINARY_OP(op_pandnot, Eigen::internal::pandnot(a, b))
EIGEN_GPU_TEST_BINARY_OP(op_pcmp_eq, Eigen::internal::pcmp_eq(a, b))
EIGEN_GPU_TEST_BINARY_OP(op_pcmp_lt, Eigen::internal::pcmp_lt(a, b))
EIGEN_GPU_TEST_BINARY_OP(op_pcmp_le, Eigen::internal::pcmp_le(a, b))
EIGEN_GPU_TEST_BINARY_OP(op_pcmp_lt_or_nan, Eigen::internal::pcmp_lt_or_nan(a, b))
EIGEN_GPU_TEST_BINARY_OP(op_pabsdiff, Eigen::internal::pabsdiff(a, b))
EIGEN_GPU_TEST_TERNARY_OP(op_pmadd, Eigen::internal::pmadd(a, b, c))
EIGEN_GPU_TEST_TERNARY_OP(op_pselect, Eigen::internal::pselect(a, b, c))
EIGEN_GPU_TEST_REDUX_OP(op_pfirst, Eigen::internal::pfirst(a))
EIGEN_GPU_TEST_REDUX_OP(op_predux, Eigen::internal::predux(a))
EIGEN_GPU_TEST_REDUX_OP(op_predux_mul, Eigen::internal::predux_mul(a))
EIGEN_GPU_TEST_REDUX_OP(op_predux_min, Eigen::internal::predux_min(a))
EIGEN_GPU_TEST_REDUX_OP(op_predux_max, Eigen::internal::predux_max(a))
// ------------------------------------------------------------------------------------------------------------------
// Kernels: thread i owns packet i. pload<float4> and pload<double2> dereference their argument as the packet, whose
// alignment is Aligned16. Every aligned load and store here addresses a whole number of 16-byte packets past a
// gpuMalloc base, which cudaMalloc documents as "suitably aligned for any kind of variable" (hipMalloc documents no
// alignment).
template <typename Packet, typename Op>
struct unary_kernel {
using Scalar = typename packet_layout<Packet>::Scalar;
static constexpr int kSize = packet_layout<Packet>::kSize;
EIGEN_PACKET_TEST_FUNC void operator()(int i, const Scalar* in, Scalar* out) const {
#if defined(EIGEN_GPU_COMPILE_PHASE)
Eigen::internal::pstore(out + i * kSize, Op::run(Eigen::internal::pload<Packet>(in + i * kSize)));
#endif
}
};
// The operands of packet i are stored back to back: a at 2i, b at 2i + 1 (and c at 3i + 2 for three operands).
template <typename Packet, typename Op>
struct binary_kernel {
using Scalar = typename packet_layout<Packet>::Scalar;
static constexpr int kSize = packet_layout<Packet>::kSize;
EIGEN_PACKET_TEST_FUNC void operator()(int i, const Scalar* in, Scalar* out) const {
#if defined(EIGEN_GPU_COMPILE_PHASE)
const Packet a = Eigen::internal::pload<Packet>(in + (2 * i) * kSize);
const Packet b = Eigen::internal::pload<Packet>(in + (2 * i + 1) * kSize);
Eigen::internal::pstore(out + i * kSize, Op::run(a, b));
#endif
}
};
template <typename Packet, typename Op>
struct ternary_kernel {
using Scalar = typename packet_layout<Packet>::Scalar;
static constexpr int kSize = packet_layout<Packet>::kSize;
EIGEN_PACKET_TEST_FUNC void operator()(int i, const Scalar* in, Scalar* out) const {
#if defined(EIGEN_GPU_COMPILE_PHASE)
const Packet a = Eigen::internal::pload<Packet>(in + (3 * i) * kSize);
const Packet b = Eigen::internal::pload<Packet>(in + (3 * i + 1) * kSize);
const Packet c = Eigen::internal::pload<Packet>(in + (3 * i + 2) * kSize);
Eigen::internal::pstore(out + i * kSize, Op::run(a, b, c));
#endif
}
};
template <typename Packet, typename Op>
struct redux_kernel {
using Scalar = typename packet_layout<Packet>::Scalar;
static constexpr int kSize = packet_layout<Packet>::kSize;
EIGEN_PACKET_TEST_FUNC void operator()(int i, const Scalar* in, Scalar* out) const {
#if defined(EIGEN_GPU_COMPILE_PHASE)
out[i] = Op::run(Eigen::internal::pload<Packet>(in + i * kSize));
#endif
}
};
template <typename Packet>
struct plset_kernel {
using Scalar = typename packet_layout<Packet>::Scalar;
static constexpr int kSize = packet_layout<Packet>::kSize;
EIGEN_PACKET_TEST_FUNC void operator()(int i, const Scalar* in, Scalar* out) const {
#if defined(EIGEN_GPU_COMPILE_PHASE)
Eigen::internal::pstore(out + i * kSize, Eigen::internal::plset<Packet>(in[i]));
#endif
}
};
// preinterpret between a scalar and its same-size integer, as the evaluator's cast path uses it on the device.
template <typename Scalar, typename Bits>
struct preinterpret_scalar_kernel {
EIGEN_PACKET_TEST_FUNC void operator()(int i, const Scalar* in, Bits* out) const {
#if defined(EIGEN_GPU_COMPILE_PHASE)
out[i] = Eigen::internal::preinterpret<Bits>(in[i]);
#endif
}
};
// Casts. The evaluator hands the narrowing form two source packets and the widening form one, from which it
// takes the leading DstPacketSize lanes; these kernels use exactly those two forms.
struct half_to_float_kernel {
EIGEN_PACKET_TEST_FUNC void operator()(int i, const Eigen::half* in, float* out) const {
#if defined(EIGEN_GPU_COMPILE_PHASE)
const ulonglong2 a = Eigen::internal::pload<ulonglong2>(in + 8 * i);
Eigen::internal::pstore(out + 4 * i, Eigen::internal::pcast<ulonglong2, float4>(a));
#else
EIGEN_UNUSED_VARIABLE(i);
EIGEN_UNUSED_VARIABLE(in);
EIGEN_UNUSED_VARIABLE(out);
#endif
}
};
struct float_to_half_kernel {
EIGEN_PACKET_TEST_FUNC void operator()(int i, const float* in, Eigen::half* out) const {
#if defined(EIGEN_GPU_COMPILE_PHASE)
const float4 a = Eigen::internal::pload<float4>(in + 8 * i);
const float4 b = Eigen::internal::pload<float4>(in + 8 * i + 4);
Eigen::internal::pstore(out + 8 * i, Eigen::internal::pcast<float4, ulonglong2>(a, b));
#else
EIGEN_UNUSED_VARIABLE(i);
EIGEN_UNUSED_VARIABLE(in);
EIGEN_UNUSED_VARIABLE(out);
#endif
}
};
// The device pass's packet traits, written into an int array: the flags the host selects operations by are the
// device's, not the host pass's, where the half packets and their traits do not exist.
#define EIGEN_GPU_TEST_TRAIT_FLAGS(X) \
X(Vectorizable) \
X(size) \
X(HasAdd) \
X(HasSub) \
X(HasMul) \
X(HasDiv) \
X(HasNegate) \
X(HasAbs) \
X(HasMin) \
X(HasMax) \
X(HasCmp) \
X(HasRound) \
X(HasSqrt) \
X(HasRsqrt) \
X(HasSign) X(HasAbsDiff) X(HasSetLinear) X(HasConj) X(HasReciprocal) X(HasExp) X(HasExpm1) X(HasLog) X(HasLog1p)
#define EIGEN_GPU_TEST_TRAIT_NAME(FLAG) #FLAG,
#define EIGEN_GPU_TEST_TRAIT_ENUM(FLAG) k##FLAG,
#define EIGEN_GPU_TEST_TRAIT_VALUE(FLAG) out[k++] = static_cast<int>(packet_traits<Scalar>::FLAG);
const char* const kTraitNames[] = {EIGEN_GPU_TEST_TRAIT_FLAGS(EIGEN_GPU_TEST_TRAIT_NAME)};
enum Trait { EIGEN_GPU_TEST_TRAIT_FLAGS(EIGEN_GPU_TEST_TRAIT_ENUM) kNumTraits };
template <typename Scalar>
struct traits_kernel {
EIGEN_PACKET_TEST_FUNC void operator()(int i, const int*, int* out) const {
#if defined(EIGEN_GPU_COMPILE_PHASE)
if (i != 0) return;
int k = 0;
EIGEN_GPU_TEST_TRAIT_FLAGS(EIGEN_GPU_TEST_TRAIT_VALUE)
#endif
}
};
template <typename Scalar>
std::vector<int> device_traits() {
Buffer<int> dummy(1), report(kNumTraits);
dummy.setZero(); // the kernel ignores it, but it is still copied to the device
report.setConstant(-1);
run_on_gpu(traits_kernel<Scalar>(), 1, dummy, report);
return std::vector<int>(report.data(), report.data() + kNumTraits);
}
// Every flag the device advertises must be covered by a part of this test or deferred to a reserved part by name.
void check_advertised_ops_are_covered(const std::vector<int>& traits, const std::vector<Trait>& covered_here) {
const std::vector<Trait> deferred = {kHasExp, kHasExpm1, kHasLog, kHasLog1p};
for (int k = kHasAdd; k < kNumTraits; ++k) {
const Trait flag = static_cast<Trait>(k);
if (traits[k] == 0) continue;
const auto covered = [flag](const std::vector<Trait>& list) {
return std::find(list.begin(), list.end(), flag) != list.end();
};
const bool ok = covered(covered_here) || covered(deferred);
if (!ok) std::cout << "advertised device op without a test: " << kTraitNames[k] << std::endl;
VERIFY(ok);
}
}
// ------------------------------------------------------------------------------------------------------------------
// Inputs.
// Every exponent step of the type, at a few mantissas, both signs.
template <typename Scalar>
std::vector<Scalar> exponent_grid(int exponent_step) {
using L = std::numeric_limits<Scalar>;
std::vector<Scalar> values;
const Scalar mantissas[] = {Scalar(1), Scalar(1.25), Scalar(1.5), Scalar(1.75), Scalar(2) - L::epsilon()};
for (int e = L::min_exponent - L::digits + 1; e <= L::max_exponent - 1; e += exponent_step) {
for (Scalar m : mantissas) {
const Scalar v = std::ldexp(m, e);
if ((std::isfinite)(v) && v != Scalar(0)) {
values.push_back(v);
values.push_back(-v);
}
}
}
return values;
}
template <typename Scalar>
std::vector<Scalar> random_values(int count) {
std::vector<Scalar> values(count);
for (Scalar& v : values) {
v = Eigen::internal::random<Scalar>(Scalar(-1), Scalar(1)) *
std::ldexp(Scalar(1), Eigen::internal::random<int>(-30, 30));
}
return values;
}
// The special values at every lane position (a run of ones shifts them), then the grid and the random values,
// padded to whole packets with ones.
template <typename Scalar>
Buffer<Scalar> unary_inputs(int packet_size, int random_count) {
std::vector<Scalar> values;
const std::vector<Scalar> specials = special_values<Scalar>();
for (int shift = 0; shift < packet_size; ++shift) {
values.insert(values.end(), shift, Scalar(1));
values.insert(values.end(), specials.begin(), specials.end());
}
const std::vector<Scalar> grid = exponent_grid<Scalar>(std::is_same<Scalar, double>::value ? 8 : 2);
values.insert(values.end(), grid.begin(), grid.end());
const std::vector<Scalar> random = random_values<Scalar>(random_count);
values.insert(values.end(), random.begin(), random.end());
while (values.size() % packet_size != 0) values.push_back(Scalar(1));
return Eigen::Map<const Buffer<Scalar>>(values.data(), values.size());
}
template <typename Scalar>
struct binary_inputs {
std::vector<Scalar> a, b;
binary_inputs() = default;
// The cross product of the special values, then random pairs, then a shifted copy of the specials so that a
// pair reaches every lane. `exclude` drops pairs the operation leaves implementation-defined.
template <typename Exclude>
binary_inputs(int packet_size, int random_count, Exclude exclude) {
const std::vector<Scalar> specials = special_values<Scalar>();
for (int shift = 0; shift < packet_size; ++shift) {
for (int k = 0; k < shift; ++k) push(Scalar(1), Scalar(1));
for (Scalar x : specials) {
for (Scalar y : specials) {
if (!exclude(x, y)) push(x, y);
}
}
}
const std::vector<Scalar> ra = random_values<Scalar>(random_count);
const std::vector<Scalar> rb = random_values<Scalar>(random_count);
for (int k = 0; k < random_count; ++k) {
if (!exclude(ra[k], rb[k])) push(ra[k], rb[k]);
}
while (a.size() % packet_size != 0) push(Scalar(1), Scalar(1));
}
void push(Scalar x, Scalar y) {
a.push_back(x);
b.push_back(y);
}
int size() const { return int(a.size()); }
// Packet-interleaved device layout: a-packet, b-packet, a-packet, ...
Buffer<Scalar> interleaved(int packet_size) const {
Buffer<Scalar> in(2 * size());
for (int p = 0; p < size() / packet_size; ++p) {
for (int l = 0; l < packet_size; ++l) {
in[(2 * p) * packet_size + l] = a[p * packet_size + l];
in[(2 * p + 1) * packet_size + l] = b[p * packet_size + l];
}
}
return in;
}
};
// Every value a half can hold, in bit-pattern order. 65536 lanes is 8192 packets, which the device sweeps in
// microseconds, so the unary operations are tested exhaustively rather than sampled.
std::vector<Eigen::half> all_half_values() {
std::vector<Eigen::half> values;
values.reserve(1 << 16);
for (int bits = 0; bits < (1 << 16); ++bits) {
values.push_back(Eigen::numext::bit_cast<Eigen::half>(static_cast<Eigen::numext::uint16_t>(bits)));
}
return values;
}
// Pairs covering the whole domain in both operands: every value against a value a stride away, plus the cross
// product of the special values. 40503 is coprime with 65536, so the second operand also runs over everything.
binary_inputs<Eigen::half> all_half_pairs(bool exclude_nan) {
const std::vector<Eigen::half> values = all_half_values();
binary_inputs<Eigen::half> pairs;
for (std::size_t i = 0; i < values.size(); ++i) {
const Eigen::half a = values[i], b = values[(i * 40503) % values.size()];
if (exclude_nan && ((Eigen::numext::isnan)(a) || (Eigen::numext::isnan)(b))) continue;
pairs.push(a, b);
}
const std::vector<float> specials = special_values<float>();
for (float x : specials) {
for (float y : specials) {
const Eigen::half a(x), b(y);
if (exclude_nan && ((Eigen::numext::isnan)(a) || (Eigen::numext::isnan)(b))) continue;
pairs.push(a, b);
}
}
while (pairs.size() % 8 != 0) pairs.push(Eigen::half(1), Eigen::half(1));
return pairs;
}
template <typename Scalar>
bool never(Scalar, Scalar) {
return false;
}
template <typename Scalar>
bool either_nan(Scalar x, Scalar y) {
return (std::isnan)(x) || (std::isnan)(y);
}
// ------------------------------------------------------------------------------------------------------------------
// Comparators.
template <typename Scalar>
struct compare_bits {
bool nan_is_nan;
bool operator()(const Scalar* ref, const Scalar* vec, int n) const {
return test::areEqualBits(ref, vec, n, nan_is_nan);
}
};
template <typename Scalar>
struct compare_ulps {
uint64_t ulps;
bool operator()(const Scalar* ref, const Scalar* vec, int n) const { return test::areWithinUlps(ref, vec, n, ulps); }
};
// ------------------------------------------------------------------------------------------------------------------
// Drivers.
// VERIFY with the operation's name in the failure report.
#define VERIFY_OP(COND) \
do { \
const bool ok_ = (COND); \
if (!ok_) std::cout << "failing operation: " << Op::name() << std::endl; \
VERIFY(ok_); \
} while (0)
template <typename Packet, typename Op, typename Ref, typename Compare>
void check_unary(const Buffer<typename packet_layout<Packet>::Scalar>& in, Ref ref, Compare compare) {
using Scalar = typename packet_layout<Packet>::Scalar;
const int kSize = packet_layout<Packet>::kSize;
Buffer<Scalar> out(in.size());
out.setConstant(Scalar(-7));
run_on_gpu(unary_kernel<Packet, Op>(), int(in.size()) / kSize, in, out);
Buffer<Scalar> expected(in.size());
for (Index k = 0; k < in.size(); ++k) expected[k] = ref(in[k]);
VERIFY_OP(compare(expected.data(), out.data(), int(in.size())));
}
template <typename Packet, typename Op, typename Ref, typename Compare>
void check_binary(const binary_inputs<typename packet_layout<Packet>::Scalar>& inputs, Ref ref, Compare compare) {
using Scalar = typename packet_layout<Packet>::Scalar;
const int kSize = packet_layout<Packet>::kSize;
const Buffer<Scalar> in = inputs.interleaved(kSize);
Buffer<Scalar> out(inputs.size());
out.setConstant(Scalar(-7));
run_on_gpu(binary_kernel<Packet, Op>(), inputs.size() / kSize, in, out);
Buffer<Scalar> expected(inputs.size());
for (int k = 0; k < inputs.size(); ++k) expected[k] = ref(inputs.a[k], inputs.b[k]);
VERIFY_OP(compare(expected.data(), out.data(), inputs.size()));
}
// A comparison must return an all-ones lane where the predicate holds and an all-zero lane elsewhere.
template <typename Packet, typename Op, typename Pred>
void check_compare(const binary_inputs<typename packet_layout<Packet>::Scalar>& inputs, Pred pred) {
using Scalar = typename packet_layout<Packet>::Scalar;
const int kSize = packet_layout<Packet>::kSize;
const Buffer<Scalar> in = inputs.interleaved(kSize);
Buffer<Scalar> out(inputs.size());
out.setConstant(Scalar(-7));
run_on_gpu(binary_kernel<Packet, Op>(), inputs.size() / kSize, in, out);
Buffer<bool> zero_mask(inputs.size());
for (int k = 0; k < inputs.size(); ++k) zero_mask[k] = !pred(inputs.a[k], inputs.b[k]);
VERIFY_OP(test::areFullBitMasks(out.data(), zero_mask.data(), inputs.size()));
}
template <typename Packet, typename Op, typename Compare>
void check_ternary(const std::vector<typename packet_layout<Packet>::Scalar>& a,
const std::vector<typename packet_layout<Packet>::Scalar>& b,
const std::vector<typename packet_layout<Packet>::Scalar>& c,
const Buffer<typename packet_layout<Packet>::Scalar>& expected, Compare compare) {
using Scalar = typename packet_layout<Packet>::Scalar;
const int kSize = packet_layout<Packet>::kSize;
const int n = int(a.size());
Buffer<Scalar> in(3 * n);
for (int p = 0; p < n / kSize; ++p) {
for (int l = 0; l < kSize; ++l) {
in[(3 * p) * kSize + l] = a[p * kSize + l];
in[(3 * p + 1) * kSize + l] = b[p * kSize + l];
in[(3 * p + 2) * kSize + l] = c[p * kSize + l];
}
}
Buffer<Scalar> out(n);
out.setConstant(Scalar(-7));
run_on_gpu(ternary_kernel<Packet, Op>(), n / kSize, in, out);
VERIFY_OP(compare(expected.data(), out.data(), n));
}
template <typename Packet, typename Op, typename Ref, typename Compare>
void check_redux(const Buffer<typename packet_layout<Packet>::Scalar>& in, Ref ref, Compare compare) {
using Scalar = typename packet_layout<Packet>::Scalar;
const int kSize = packet_layout<Packet>::kSize;
const int n = int(in.size()) / kSize;
Buffer<Scalar> out(n);
out.setConstant(Scalar(-7));
run_on_gpu(redux_kernel<Packet, Op>(), n, in, out);
Buffer<Scalar> expected(n);
for (int p = 0; p < n; ++p) expected[p] = ref(in.data() + p * kSize);
VERIFY_OP(compare(expected.data(), out.data(), n));
}
// Runs a kernel once per packet on the device, for the shared data-movement cases.
struct launch_on_gpu {
template <typename Kernel, typename Input, typename Output>
void operator()(const Kernel& kernel, int count, const Input& input, Output& output) const {
run_on_gpu(kernel, count, input, output);
}
};
// plset with every input as a base, large values and negative zero included. `ref` adds a lane index in the type's
// own arithmetic, since a half sum has to round exactly once; that addition need not keep a NaN payload.
template <typename Packet, typename Ref>
void check_plset(const Buffer<typename packet_layout<Packet>::Scalar>& in, Ref ref) {
using Scalar = typename packet_layout<Packet>::Scalar;
const int kSize = packet_layout<Packet>::kSize;
Buffer<Scalar> out(in.size() * kSize), expected(in.size() * kSize);
out.setConstant(Scalar(-7));
run_on_gpu(plset_kernel<Packet>(), int(in.size()), in, out);
for (Index k = 0; k < out.size(); ++k) {
expected[k] = (k % kSize == 0) ? in[k / kSize] : ref(in[k / kSize], int(k % kSize));
}
VERIFY(test::areEqualBits(expected.data(), out.data(), int(out.size())) && "plset");
}
// ptrue and pzero: every bit of every lane set, or every bit cleared.
template <typename Packet, typename Op>
void check_full_mask(const Buffer<typename packet_layout<Packet>::Scalar>& in, bool expect_zero) {
using Scalar = typename packet_layout<Packet>::Scalar;
Buffer<Scalar> out(in.size());
out.setConstant(Scalar(-7));
run_on_gpu(unary_kernel<Packet, Op>(), int(in.size()) / packet_layout<Packet>::kSize, in, out);
const Buffer<bool> zero_mask = Buffer<bool>::Constant(in.size(), expect_zero);
VERIFY_OP(test::areFullBitMasks(out.data(), zero_mask.data(), int(in.size())));
}
// Points where the standard fixes the result exactly, whatever the implementation's accuracy elsewhere. The
// comparison is bitwise, so the sign of a zero counts; NaN matches NaN whatever the payload.
template <typename Packet, typename Op>
void check_special_values(
const std::vector<std::pair<typename packet_layout<Packet>::Scalar, typename packet_layout<Packet>::Scalar>>&
cases) {
using Scalar = typename packet_layout<Packet>::Scalar;
const int kSize = packet_layout<Packet>::kSize;
std::vector<Scalar> in_values, expected_values;
for (const auto& one : cases) {
in_values.push_back(one.first);
expected_values.push_back(one.second);
}
// Pad to a whole number of packets by repeating the first case; only the real cases are compared.
while (in_values.size() % kSize != 0) {
in_values.push_back(cases[0].first);
expected_values.push_back(cases[0].second);
}
const Buffer<Scalar> in = Eigen::Map<const Buffer<Scalar>>(in_values.data(), in_values.size());
Buffer<Scalar> out(in.size());
out.setConstant(Scalar(-7));
run_on_gpu(unary_kernel<Packet, Op>(), int(in.size()) / kSize, in, out);
VERIFY_OP(test::areEqualBits(expected_values.data(), out.data(), int(cases.size())));
}
// ------------------------------------------------------------------------------------------------------------------
// Parts 2 and 4: the transcendental operations. Accuracy over the ordinary range is a named ULP budget against a
// reference computed one type wider; the values the standard fixes are checked exactly.
template <typename Scalar>
void packetmath_gpu_real_math() {
using Packet = typename packet_traits<Scalar>::type;
using Wider = typename wider_type<Scalar>::type;
const int kSize = packet_layout<Packet>::kSize;
const MathUlpBudget& budget = std::is_same<Scalar, double>::value ? kDoubleUlps : kFloatUlps;
const std::vector<int> traits = device_traits<Scalar>();
VERIFY_IS_EQUAL(traits[kHasExp], 1);
VERIFY_IS_EQUAL(traits[kHasLog], 1);
const Scalar zero(0), one(1), inf = std::numeric_limits<Scalar>::infinity();
const Scalar nan = std::numeric_limits<Scalar>::quiet_NaN();
const Scalar lowest = std::numeric_limits<Scalar>::lowest(), largest = (std::numeric_limits<Scalar>::max)();
// Inputs the logarithms accept: positive, plus the special values, which the budgeted comparison tolerates
// because a NaN reference matches a NaN result.
const Buffer<Scalar> in = unary_inputs<Scalar>(kSize, 1 << 18);
Buffer<Scalar> positive(in.size());
for (Index k = 0; k < in.size(); ++k) positive[k] = std::abs(in[k]);
// log1p's domain is (-1, +inf), and the interesting half of it is the run just above -1: |x| - 0.5 never
// reaches below -0.5, so it would leave the argument reduction there untested. Even lanes therefore hold
// -1 + u with u drawn log-uniformly over [2^-digits, 1), which walks (-1, 0) from a single ulp above -1 up to
// 0; odd lanes keep |x| - 0.5, which covers (-0.5, +inf) and carries the special values.
Buffer<Scalar> above_minus_one(in.size());
for (Index k = 0; k < in.size(); ++k) {
if (k % 2 == 0) {
const int exponent = Eigen::internal::random<int>(1, Eigen::NumTraits<Scalar>::digits());
const Scalar significand = Eigen::internal::random<Scalar>(Scalar(1), Scalar(2));
above_minus_one[k] = Scalar(-1) + std::ldexp(significand, -exponent);
} else {
above_minus_one[k] = std::abs(in[k]) - Scalar(0.5);
}
}
check_unary<Packet, op_pexp>(
in, [](Scalar x) { return static_cast<Scalar>(std::exp(static_cast<Wider>(x))); },
compare_ulps<Scalar>{budget.exp});
check_unary<Packet, op_pexp2>(
in, [](Scalar x) { return static_cast<Scalar>(std::exp2(static_cast<Wider>(x))); },
compare_ulps<Scalar>{budget.exp2});
check_unary<Packet, op_pexpm1>(
in, [](Scalar x) { return static_cast<Scalar>(std::expm1(static_cast<Wider>(x))); },
compare_ulps<Scalar>{budget.expm1});
check_unary<Packet, op_plog>(
positive, [](Scalar x) { return static_cast<Scalar>(std::log(static_cast<Wider>(x))); },
compare_ulps<Scalar>{budget.log});
check_unary<Packet, op_plog1p>(
above_minus_one, [](Scalar x) { return static_cast<Scalar>(std::log1p(static_cast<Wider>(x))); },
compare_ulps<Scalar>{budget.log1p});
check_special_values<Packet, op_pexp>(
{{zero, one}, {-zero, one}, {-inf, zero}, {inf, inf}, {nan, nan}, {lowest, zero}, {largest, inf}});
check_special_values<Packet, op_pexp2>(
{{zero, one}, {-zero, one}, {one, Scalar(2)}, {-inf, zero}, {inf, inf}, {nan, nan}});
// expm1 preserves the sign of a zero, and saturates to -1 at minus infinity.
check_special_values<Packet, op_pexpm1>(
{{zero, zero}, {-zero, -zero}, {-inf, Scalar(-1)}, {inf, inf}, {nan, nan}, {lowest, Scalar(-1)}});
check_special_values<Packet, op_plog>(
{{one, zero}, {zero, -inf}, {-zero, -inf}, {-one, nan}, {-inf, nan}, {inf, inf}, {nan, nan}});
check_special_values<Packet, op_plog1p>(
{{zero, zero}, {-zero, -zero}, {Scalar(-1), -inf}, {Scalar(-2), nan}, {-inf, nan}, {inf, inf}, {nan, nan}});
}
// ------------------------------------------------------------------------------------------------------------------
// The core of a floating-point packet type: loads and stores, arithmetic, min/max, rounding, bit operations,
// comparisons, select, reductions, sqrt and rsqrt.
template <typename Scalar>
Scalar rsqrt_reference(Scalar x) {
using Wider = typename wider_type<Scalar>::type;
return static_cast<Scalar>(Wider(1) / std::sqrt(static_cast<Wider>(x)));
}
template <typename Scalar>
void packetmath_gpu_real_core() {
using Packet = typename packet_traits<Scalar>::type;
const int kSize = packet_layout<Packet>::kSize;
using Bits = typename Eigen::numext::get_integer_by_size<sizeof(Scalar)>::unsigned_type;
const compare_bits<Scalar> bits{true};
const compare_bits<Scalar> bits_and_payload{false};
const auto values = test::areEqual<Scalar>;
const uint64_t rsqrt_ulps = std::is_same<Scalar, double>::value ? kRsqrtDoubleUlps : kRsqrtFloatUlps;
// The device's view of the type, and what this part covers of it.
const std::vector<int> traits = device_traits<Scalar>();
std::cout << "device packet_traits<" << typeid(Scalar).name() << ">:";
for (int k = 0; k < kNumTraits; ++k) std::cout << " " << kTraitNames[k] << "=" << traits[k];
std::cout << std::endl;
VERIFY_IS_EQUAL(traits[kVectorizable], 1);
VERIFY_IS_EQUAL(traits[ksize], kSize);
VERIFY_IS_EQUAL(traits[kHasCmp], 1);
check_advertised_ops_are_covered(
traits, {kHasAdd, kHasSub, kHasMul, kHasDiv, kHasNegate, kHasAbs, kHasMin, kHasMax, kHasCmp, kHasRound, kHasSqrt,
kHasRsqrt, kHasSign, kHasAbsDiff, kHasSetLinear, kHasConj});
const Buffer<Scalar> in = unary_inputs<Scalar>(kSize, 1 << 18);
const int n = int(in.size()) / kSize;
// Loads and stores keep every bit, NaN payloads included.
check_unary<Packet, op_identity>(
in, [](Scalar x) { return x; }, bits_and_payload);
test::packetmath_data_movement<Packet>(in, launch_on_gpu());
check_plset<Packet>(in, [](Scalar base, int lane) { return Scalar(base + Scalar(lane)); });
// Sign manipulation and rounding: fixed bit for bit, including the sign of a zero.
check_unary<Packet, op_pnegate>(
in, [](Scalar x) { return -x; }, bits);
check_unary<Packet, op_pconj>(
in, [](Scalar x) { return x; }, bits);
check_unary<Packet, op_pabs>(
in, [](Scalar x) { return std::abs(x); }, bits);
check_unary<Packet, op_pfloor>(
in, [](Scalar x) { return std::floor(x); }, bits);
check_unary<Packet, op_pceil>(
in, [](Scalar x) { return std::ceil(x); }, bits);
check_unary<Packet, op_print>(
in, [](Scalar x) { return std::rint(x); }, bits);
check_unary<Packet, op_ptrunc>(
in, [](Scalar x) { return std::trunc(x); }, bits);
check_unary<Packet, op_pround>(
in, [](Scalar x) { return std::round(x); }, bits);
check_unary<Packet, op_preinterpret_self>(
in, [](Scalar x) { return x; }, bits_and_payload);
check_unary<Packet, op_psign>(
in, [](Scalar x) { return Eigen::numext::sign(x); }, bits);
// No ULP budget admits a lost zero sign or an overflow.
const uint64_t kFar = (std::numeric_limits<uint64_t>::max)();
VERIFY_IS_EQUAL(test::ulp_distance(Scalar(0), Scalar(-0.0)), kFar);
VERIFY_IS_EQUAL(test::ulp_distance(std::numeric_limits<Scalar>::infinity(), (std::numeric_limits<Scalar>::max)()),
kFar);
VERIFY_IS_EQUAL(test::ulp_distance(Scalar(0), std::numeric_limits<Scalar>::denorm_min()), uint64_t(1));
if (std::is_same<Scalar, float>::value) {
check_unary<Packet, op_psqrt>(
in, [](Scalar x) { return std::sqrt(x); }, compare_ulps<Scalar>{kSqrtFloatUlps});
} else {
check_unary<Packet, op_psqrt>(
in, [](Scalar x) { return std::sqrt(x); }, bits);
}
check_unary<Packet, op_prsqrt>(in, rsqrt_reference<Scalar>, compare_ulps<Scalar>{rsqrt_ulps});
check_full_mask<Packet, op_ptrue>(in, /*expect_zero=*/false);
check_full_mask<Packet, op_pzero>(in, /*expect_zero=*/true);
// Arithmetic: IEEE operations, so the host's own results are the reference, bit for bit.
const binary_inputs<Scalar> pairs(kSize, 1 << 17, never<Scalar>);
check_binary<Packet, op_padd>(pairs, test::REF_ADD<Scalar>, bits);
check_binary<Packet, op_psub>(pairs, test::REF_SUB<Scalar>, bits);
check_binary<Packet, op_pmul>(pairs, test::REF_MUL<Scalar>, bits);
check_binary<Packet, op_pdiv>(pairs, test::REF_DIV<Scalar>, bits);
// The sign of a zero difference is not part of pabsdiff's contract.
check_binary<Packet, op_pabsdiff>(
pairs, [](Scalar x, Scalar y) { return x < y ? y - x : x - y; }, values);
// Plain pmin/pmax leave NaN operands implementation-defined (the device uses fminf/fmaxf); the propagating
// variants fix them.
const binary_inputs<Scalar> number_pairs(kSize, 1 << 16, either_nan<Scalar>);
check_binary<Packet, op_pmin>(
number_pairs, [](Scalar x, Scalar y) { return (std::min)(x, y); }, values);
check_binary<Packet, op_pmax>(
number_pairs, [](Scalar x, Scalar y) { return (std::max)(x, y); }, values);
check_binary<Packet, op_pmin_numbers>(
pairs, [](Scalar x, Scalar y) { return std::fmin(x, y); }, values);
check_binary<Packet, op_pmax_numbers>(
pairs, [](Scalar x, Scalar y) { return std::fmax(x, y); }, values);
check_binary<Packet, op_pmin_nan>(
pairs,
[](Scalar x, Scalar y) {
return ((std::isnan)(x) || (std::isnan)(y)) ? std::numeric_limits<Scalar>::quiet_NaN() : (std::min)(x, y);
},
values);
check_binary<Packet, op_pmax_nan>(
pairs,
[](Scalar x, Scalar y) {
return ((std::isnan)(x) || (std::isnan)(y)) ? std::numeric_limits<Scalar>::quiet_NaN() : (std::max)(x, y);
},
values);
// Bit operations act on the representation, payloads included.
check_binary<Packet, op_pand>(
pairs, [](Scalar x, Scalar y) { return bit_cast<Scalar>(Bits(bit_cast<Bits>(x) & bit_cast<Bits>(y))); },
bits_and_payload);
check_binary<Packet, op_por>(
pairs, [](Scalar x, Scalar y) { return bit_cast<Scalar>(Bits(bit_cast<Bits>(x) | bit_cast<Bits>(y))); },
bits_and_payload);
check_binary<Packet, op_pxor>(
pairs, [](Scalar x, Scalar y) { return bit_cast<Scalar>(Bits(bit_cast<Bits>(x) ^ bit_cast<Bits>(y))); },
bits_and_payload);
check_binary<Packet, op_pandnot>(
pairs, [](Scalar x, Scalar y) { return bit_cast<Scalar>(Bits(bit_cast<Bits>(x) & ~bit_cast<Bits>(y))); },
bits_and_payload);
// Comparisons: full-bit masks, false on any NaN operand.
check_compare<Packet, op_pcmp_eq>(pairs, [](Scalar x, Scalar y) { return x == y; });
check_compare<Packet, op_pcmp_lt>(pairs, [](Scalar x, Scalar y) { return x < y; });
check_compare<Packet, op_pcmp_le>(pairs, [](Scalar x, Scalar y) { return x <= y; });
check_compare<Packet, op_pcmp_lt_or_nan>(pairs, [](Scalar x, Scalar y) { return !(x >= y); });
{
// pmadd may or may not be contracted by the device compiler (ptxas fuses a*b+c by default): either the
// fused or the separately rounded result is acceptable until the backend provides an explicit fma.
const int count = 1 << 16;
std::vector<Scalar> a = random_values<Scalar>(count), b = random_values<Scalar>(count),
c = random_values<Scalar>(count);
const Scalar epsilon = NumTraits<Scalar>::epsilon();
const int rounding_case = int(a.size());
a.push_back(Scalar(1) + epsilon);
b.push_back(Scalar(1) - epsilon);
c.push_back(Scalar(-1));
const std::vector<Scalar> specials = special_values<Scalar>();
for (Scalar x : specials) {
for (Scalar y : specials) {
a.push_back(x);
b.push_back(y);
c.push_back(specials[(a.size() * 7) % specials.size()]);
}
}
while (a.size() % kSize != 0) {
a.push_back(Scalar(1));
b.push_back(Scalar(1));
c.push_back(Scalar(1));
}
const int n3 = int(a.size());
Buffer<Scalar> fused(n3), unfused(n3);
for (int k = 0; k < n3; ++k) {
fused[k] = std::fma(a[k], b[k], c[k]);
// A statement boundary alone still permits contraction with -ffp-contract=fast.
const volatile Scalar product = a[k] * b[k];
unfused[k] = product + c[k];
}
VERIFY_IS_EQUAL(fused[rounding_case], -epsilon * epsilon);
VERIFY_IS_EQUAL(unfused[rounding_case], Scalar(0));
const auto fused_or_not = [&](const Scalar* ref, const Scalar* vec, int m) {
for (int k = 0; k < m; ++k) {
const bool ok = test::ulp_distance(ref[k], vec[k]) == 0 || test::ulp_distance(unfused[k], vec[k]) == 0;
if (!ok) {
std::cout << "pmadd lane " << k << ": " << vec[k] << " is neither fma " << ref[k] << " nor a*b+c "
<< unfused[k] << std::endl;
return false;
}
}
return true;
};
check_ternary<Packet, op_pmadd>(a, b, c, fused, fused_or_not);
// pselect with full-bit masks picks the second operand where the mask is set, bit for bit.
std::vector<Scalar> mask(n3);
Buffer<Scalar> selected(n3);
const Scalar all_ones = Eigen::numext::bit_cast<Scalar>(Bits(~Bits(0)));
for (int k = 0; k < n3; ++k) {
mask[k] = Eigen::internal::random<bool>() ? all_ones : Scalar(0);
selected[k] = Eigen::numext::bit_cast<Bits>(mask[k]) != Bits(0) ? a[k] : b[k];
}
check_ternary<Packet, op_pselect>(mask, a, b, selected, bits_and_payload);
}
// Reductions. Sums and products follow the device's lane order, which the host reproduces.
check_redux<Packet, op_pfirst>(
in, [](const Scalar* p) { return p[0]; }, bits_and_payload);
check_redux<Packet, op_predux>(
in,
[kSize](const Scalar* p) {
Scalar s = p[0];
for (int l = 1; l < kSize; ++l) s = s + p[l];
return s;
},
bits);
check_redux<Packet, op_predux_mul>(
in,
[kSize](const Scalar* p) {
Scalar s = p[0];
for (int l = 1; l < kSize; ++l) s = s * p[l];
return s;
},
bits);
Buffer<Scalar> numbers(in.size());
for (Index k = 0; k < in.size(); ++k) numbers[k] = (std::isnan)(in[k]) ? Scalar(1) : in[k];
check_redux<Packet, op_predux_min>(
numbers,
[kSize](const Scalar* p) {
Scalar s = p[0];
for (int l = 1; l < kSize; ++l) s = (std::min)(s, p[l]);
return s;
},
values);
check_redux<Packet, op_predux_max>(
numbers,
[kSize](const Scalar* p) {
Scalar s = p[0];
for (int l = 1; l < kSize; ++l) s = (std::max)(s, p[l]);
return s;
},
values);
}
// ------------------------------------------------------------------------------------------------------------------
// Parts 5 and 6: the half packets. Packet4h2 is eight halves in four half2 lanes and exists only in the device
// pass. References are computed in float and rounded once, which is exact for the arithmetic operations because a
// float mantissa is at least twice a half's plus two bits.
using HalfPacket = ulonglong2;
// A half operation whose reference is the float computation rounded back.
Eigen::half half_of(float x) { return Eigen::half(x); }
Eigen::half half_add(Eigen::half a, Eigen::half b) { return half_of(float(a) + float(b)); }
Eigen::half half_mul(Eigen::half a, Eigen::half b) { return half_of(float(a) * float(b)); }
void packetmath_gpu_half_core() {
using Scalar = Eigen::half;
using Packet = HalfPacket;
using Bits = uint16_t;
const int kSize = packet_layout<Packet>::kSize;
const compare_bits<Scalar> bits{true};
const compare_bits<Scalar> bits_and_payload{false};
const auto values = test::areEqual<Scalar>;
const std::vector<int> traits = device_traits<Scalar>();
std::cout << "device packet_traits<half>:";
for (int k = 0; k < kNumTraits; ++k) std::cout << " " << kTraitNames[k] << "=" << traits[k];
std::cout << std::endl;
VERIFY_IS_EQUAL(traits[kVectorizable], 1);
VERIFY_IS_EQUAL(traits[ksize], kSize);
// The hygiene sweep turned these off: there is no rounding operation and no psign for the half packets.
VERIFY_IS_EQUAL(traits[kHasRound], 0);
VERIFY_IS_EQUAL(traits[kHasSign], 0);
check_advertised_ops_are_covered(traits, {kHasAdd, kHasSub, kHasMul, kHasDiv, kHasNegate, kHasAbs, kHasMin, kHasMax,
kHasSqrt, kHasRsqrt, kHasSetLinear, kHasConj, kHasAbsDiff});
// Exhaustive: every value a half can hold.
const std::vector<Scalar> all = all_half_values();
const Buffer<Scalar> in = Eigen::Map<const Buffer<Scalar>>(all.data(), all.size());
const int n = int(in.size()) / kSize;
check_unary<Packet, op_identity>(
in, [](Scalar x) { return x; }, bits_and_payload);
// The sign of a NaN survives neither __hneg2 nor __habs2, as on the float packets; the value stays NaN.
check_unary<Packet, op_pnegate>(
in, [](Scalar x) { return bit_cast<Scalar>(Bits(bit_cast<Bits>(x) ^ 0x8000u)); }, bits);
check_unary<Packet, op_pabs>(
in, [](Scalar x) { return bit_cast<Scalar>(Bits(bit_cast<Bits>(x) & 0x7fffu)); }, bits);
check_unary<Packet, op_pconj>(
in, [](Scalar x) { return x; }, bits_and_payload);
// The half2 intrinsics quiet a signalling NaN, so data movement matches NaNs by value. The lane index is added in
// half, so the plset reference rounds once, as the packet does.
test::packetmath_data_movement<Packet>(in, launch_on_gpu(), /*nan_payloads=*/false);
check_plset<Packet>(in, [](Scalar base, int lane) { return half_add(base, half_of(float(lane))); });
// Arithmetic. Rounding once from float is the correctly rounded half result.
const binary_inputs<Scalar> pairs = all_half_pairs(/*exclude_nan=*/false);
const binary_inputs<Scalar> numbers = all_half_pairs(/*exclude_nan=*/true);
check_binary<Packet, op_padd>(pairs, half_add, bits);
check_binary<Packet, op_psub>(
pairs, [](Scalar x, Scalar y) { return half_of(float(x) - float(y)); }, bits);
check_binary<Packet, op_pmul>(pairs, half_mul, bits);
check_binary<Packet, op_pdiv>(
pairs, [](Scalar x, Scalar y) { return half_of(float(x) / float(y)); }, bits);
// Plain min/max leave a NaN operand implementation-defined, as for the float packets.
check_binary<Packet, op_pmin>(
numbers, [](Scalar x, Scalar y) { return float(x) < float(y) ? x : y; }, values);
check_binary<Packet, op_pmax>(
numbers, [](Scalar x, Scalar y) { return float(x) > float(y) ? x : y; }, values);
// Bit operations act on the 16-bit representation.
check_binary<Packet, op_pand>(
pairs, [](Scalar x, Scalar y) { return bit_cast<Scalar>(Bits(bit_cast<Bits>(x) & bit_cast<Bits>(y))); },
bits_and_payload);
check_binary<Packet, op_por>(
pairs, [](Scalar x, Scalar y) { return bit_cast<Scalar>(Bits(bit_cast<Bits>(x) | bit_cast<Bits>(y))); },
bits_and_payload);
check_binary<Packet, op_pxor>(
pairs, [](Scalar x, Scalar y) { return bit_cast<Scalar>(Bits(bit_cast<Bits>(x) ^ bit_cast<Bits>(y))); },
bits_and_payload);
check_binary<Packet, op_pandnot>(
pairs, [](Scalar x, Scalar y) { return bit_cast<Scalar>(Bits(bit_cast<Bits>(x) & ~bit_cast<Bits>(y))); },
bits_and_payload);
// Comparisons produce all-ones or all-zero 16-bit lanes.
check_compare<Packet, op_pcmp_eq>(pairs, [](Scalar x, Scalar y) { return float(x) == float(y); });
check_compare<Packet, op_pcmp_lt>(pairs, [](Scalar x, Scalar y) { return float(x) < float(y); });
check_compare<Packet, op_pcmp_le>(pairs, [](Scalar x, Scalar y) { return float(x) <= float(y); });
check_full_mask<Packet, op_ptrue>(in, /*expect_zero=*/false);
check_full_mask<Packet, op_pzero>(in, /*expect_zero=*/true);
{
// pselect with full-bit masks picks lane by lane.
const int count = numbers.size();
std::vector<Scalar> mask(count);
Buffer<Scalar> selected(count);
for (int k = 0; k < count; ++k) {
const bool set = Eigen::internal::random<bool>();
mask[k] = set ? bit_cast<Scalar>(Bits(0xffffu)) : bit_cast<Scalar>(Bits(0x0000u));
selected[k] = set ? numbers.a[k] : numbers.b[k];
}
check_ternary<Packet, op_pselect>(mask, numbers.a, numbers.b, selected, bits_and_payload);
}
{
// pmadd is __hfma2: one rounding, so the reference is the float fma rounded once.
const int count = numbers.size();
Buffer<Scalar> expected(count);
for (int k = 0; k < count; ++k) {
expected[k] = half_of(std::fma(float(numbers.a[k]), float(numbers.b[k]), float(numbers.a[k])));
}
check_ternary<Packet, op_pmadd>(numbers.a, numbers.b, numbers.a, expected, bits);
}
// Adjacent opposite-sign lanes cancel before any cross-pair addition can overflow.
Buffer<Scalar> cancellation(8);
cancellation << Scalar(60000), Scalar(-60000), Scalar(60000), Scalar(-60000), Scalar(0), Scalar(0), Scalar(0),
Scalar(0);
check_redux<Packet, op_predux>(
cancellation, [](const Scalar*) { return Scalar(0); }, bits);
// Reductions follow the lane tree of the implementation, so the reference rounds in the same order.
const Buffer<Scalar> finite = [&] {
std::vector<Scalar> v;
for (Index k = 0; k < in.size(); ++k) {
const float x = float(in[k]);
v.push_back((std::isfinite)(x) && std::abs(x) < 4.0f ? in[k] : Scalar(1));
}
return Eigen::Map<const Buffer<Scalar>>(v.data(), v.size()).eval();
}();
check_redux<Packet, op_predux>(
finite,
[](const Scalar* p) {
return half_add(half_add(half_add(half_add(p[0], p[1]), half_add(p[2], p[3])), half_add(p[4], p[5])),
half_add(p[6], p[7]));
},
bits);
check_redux<Packet, op_predux_mul>(
finite,
[](const Scalar* p) {
return half_mul(half_mul(half_mul(p[0], p[2]), half_mul(p[4], p[6])),
half_mul(half_mul(p[1], p[3]), half_mul(p[5], p[7])));
},
bits);
check_redux<Packet, op_predux_min>(
finite,
[](const Scalar* p) {
Scalar m = p[0];
for (int l = 1; l < 8; ++l) m = float(p[l]) < float(m) ? p[l] : m;
return m;
},
values);
check_redux<Packet, op_predux_max>(
finite,
[](const Scalar* p) {
Scalar m = p[0];
for (int l = 1; l < 8; ++l) m = float(p[l]) > float(m) ? p[l] : m;
return m;
},
values);
check_redux<Packet, op_pfirst>(
in, [](const Scalar* p) { return p[0]; }, bits_and_payload);
// Casts, in the two forms the evaluator uses.
{
const int packets = int(in.size()) / kSize;
Buffer<float> as_float(packets * 4);
as_float.setConstant(-7.0f);
run_on_gpu(half_to_float_kernel(), packets, in, as_float);
for (int k = 0; k < packets * 4; ++k) {
const float want = static_cast<float>(in[(k / 4) * kSize + (k % 4)]);
VERIFY(test::areEqualBits(&want, as_float.data() + k, 1) && "pcast<Packet4h2, float4>");
}
// The narrowing cast has to round, so its inputs must not be representable as half to begin with: a float
// widened from a half is, and would let any rounding rule pass. Every tie of the half grid is generated
// instead -- the midpoint between each pair of adjacent halves, from the subnormals up to the largest finite
// one -- with the neighbours of each tie, then the overflow and underflow boundaries.
std::vector<float> float_values;
for (unsigned bits = 0; bits + 1 < 0x7c00u; ++bits) {
const float below = float(bit_cast<Scalar>(Bits(bits)));
const float above = float(bit_cast<Scalar>(Bits(bits + 1)));
const float tie = 0.5f * (below + above); // rounds to even, so to one of the two only every other time
for (float value : {tie, std::nextafterf(tie, below), std::nextafterf(tie, above)}) {
float_values.push_back(value);
float_values.push_back(-value);
}
}
const float largest_half = float(bit_cast<Scalar>(Bits(0x7bffu)));
const float overflow_tie = 65520.0f; // halfway from the largest half to where the next one would be
for (float value :
{largest_half, std::nextafterf(largest_half, 1e30f), std::nextafterf(overflow_tie, 0.0f), overflow_tie,
std::nextafterf(overflow_tie, 1e30f), 65536.0f, (std::numeric_limits<float>::max)(),
std::numeric_limits<float>::infinity(), std::numeric_limits<float>::denorm_min(), 0.0f}) {
float_values.push_back(value);
float_values.push_back(-value);
}
while (float_values.size() % 8 != 0) float_values.push_back(0.0f);
const int cast_packets = int(float_values.size()) / 8;
const Buffer<float> floats = Eigen::Map<const Buffer<float>>(float_values.data(), Index(float_values.size()));
Buffer<Scalar> as_half(float_values.size());
as_half.setConstant(Scalar(-7));
run_on_gpu(float_to_half_kernel(), cast_packets, floats, as_half);
Buffer<Scalar> want(float_values.size());
for (Index k = 0; k < want.size(); ++k) want[k] = half_of(floats[k]);
VERIFY(test::areEqualBits(want.data(), as_half.data(), int(want.size())) && "pcast<float4, Packet4h2>");
}
}
void packetmath_gpu_half_math() {
using Scalar = Eigen::half;
using Packet = HalfPacket;
using Bits = uint16_t;
const std::vector<Scalar> all = all_half_values();
const Buffer<Scalar> in = Eigen::Map<const Buffer<Scalar>>(all.data(), all.size());
Buffer<Scalar> positive(in.size());
for (Index k = 0; k < in.size(); ++k) positive[k] = bit_cast<Scalar>(Bits(bit_cast<Bits>(in[k]) & 0x7fffu));
// h2sqrt, h2rsqrt, h2log and h2exp against the float computation rounded to half. The device functions are not
// documented to be correctly rounded in half, so allow one half ULP.
const uint64_t kHalfMathUlps = 1;
check_unary<Packet, op_psqrt>(
positive, [](Scalar x) { return half_of(std::sqrt(float(x))); }, compare_ulps<Scalar>{kHalfMathUlps});
check_unary<Packet, op_prsqrt>(
positive, [](Scalar x) { return half_of(1.0f / std::sqrt(float(x))); }, compare_ulps<Scalar>{kHalfMathUlps});
check_unary<Packet, op_plog>(
positive, [](Scalar x) { return half_of(std::log(float(x))); }, compare_ulps<Scalar>{kHalfMathUlps});
check_unary<Packet, op_pexp>(
in, [](Scalar x) { return half_of(std::exp(float(x))); }, compare_ulps<Scalar>{kHalfMathUlps});
check_unary<Packet, op_plog1p>(
in, [](Scalar x) { return half_of(std::log1p(float(x))); }, compare_ulps<Scalar>{kHalfMathUlps});
check_unary<Packet, op_pexpm1>(
in, [](Scalar x) { return half_of(std::expm1(float(x))); }, compare_ulps<Scalar>{kHalfMathUlps});
const Scalar zero(0.0f), one(1.0f), inf = std::numeric_limits<Scalar>::infinity();
const Scalar nan = std::numeric_limits<Scalar>::quiet_NaN();
check_special_values<Packet, op_pexp>({{zero, one}, {-zero, one}, {-inf, zero}, {inf, inf}, {nan, nan}});
check_special_values<Packet, op_plog>({{one, zero}, {zero, -inf}, {-one, nan}, {inf, inf}, {nan, nan}});
check_special_values<Packet, op_psqrt>({{zero, zero}, {-zero, -zero}, {one, one}, {inf, inf}, {nan, nan}});
}
// ------------------------------------------------------------------------------------------------------------------
// Part 7: types without a device packet run the scalar fallbacks of GenericPacketMath.h, which must agree with the
// host's scalar fallbacks bit for bit; preinterpret is the bit_cast the cast path relies on.
template <typename Scalar>
void check_scalar_fallback_common(const binary_inputs<Scalar>& pairs, const Buffer<Scalar>& in) {
const compare_bits<Scalar> bits{true};
const std::vector<int> traits = device_traits<Scalar>();
VERIFY_IS_EQUAL(traits[kVectorizable], 0);
VERIFY_IS_EQUAL(traits[ksize], 1);
check_binary<Scalar, op_padd>(pairs, test::REF_ADD<Scalar>, bits);
check_binary<Scalar, op_pmul>(pairs, test::REF_MUL<Scalar>, bits);
check_binary<Scalar, op_pmin>(
pairs, [](Scalar x, Scalar y) { return Eigen::internal::pmin(x, y); }, bits);
check_binary<Scalar, op_pmax>(
pairs, [](Scalar x, Scalar y) { return Eigen::internal::pmax(x, y); }, bits);
check_binary<Scalar, op_pand>(
pairs, [](Scalar x, Scalar y) { return Eigen::internal::pand(x, y); }, bits);
check_binary<Scalar, op_por>(
pairs, [](Scalar x, Scalar y) { return Eigen::internal::por(x, y); }, bits);
check_binary<Scalar, op_pxor>(
pairs, [](Scalar x, Scalar y) { return Eigen::internal::pxor(x, y); }, bits);
check_binary<Scalar, op_pcmp_eq>(
pairs, [](Scalar x, Scalar y) { return Eigen::internal::pcmp_eq(x, y); }, bits);
check_binary<Scalar, op_pcmp_lt>(
pairs, [](Scalar x, Scalar y) { return Eigen::internal::pcmp_lt(x, y); }, bits);
check_binary<Scalar, op_pcmp_le>(
pairs, [](Scalar x, Scalar y) { return Eigen::internal::pcmp_le(x, y); }, bits);
check_unary<Scalar, op_identity>(
in, [](Scalar x) { return x; }, bits);
{
// pselect on a scalar is a ternary on the mask's truth value.
const int n = pairs.size();
std::vector<Scalar> mask(n);
Buffer<Scalar> selected(n);
for (int k = 0; k < n; ++k) {
mask[k] = Eigen::internal::random<bool>() ? Eigen::internal::ptrue(Scalar(0)) : Eigen::internal::pzero(Scalar(0));
selected[k] = Eigen::internal::pselect(Scalar(mask[k]), Scalar(pairs.a[k]), Scalar(pairs.b[k]));
}
check_ternary<Scalar, op_pselect>(mask, pairs.a, pairs.b, selected, bits);
}
}
template <typename Scalar>
binary_inputs<Scalar> integer_pairs(int count) {
binary_inputs<Scalar> pairs;
// Signed operands stay within 100 in magnitude, so their sums and products stay in range; unsigned operands reach
// 200, whose uint8_t sums and products wrap, as the REF_* references do.
const Scalar bound = Scalar(NumTraits<Scalar>::IsSigned ? 100 : 200);
for (int k = 0; k < count; ++k) {
pairs.push(Eigen::internal::random<Scalar>(NumTraits<Scalar>::IsSigned ? Scalar(-bound) : Scalar(0), bound),
Eigen::internal::random<Scalar>(NumTraits<Scalar>::IsSigned ? Scalar(-bound) : Scalar(0), bound));
}
return pairs;
}
template <typename Scalar>
void packetmath_gpu_integer_fallback() {
const compare_bits<Scalar> bits{true};
const binary_inputs<Scalar> pairs = integer_pairs<Scalar>(1 << 12);
const Buffer<Scalar> in = Eigen::Map<const Buffer<Scalar>>(pairs.a.data(), pairs.size());
check_scalar_fallback_common<Scalar>(pairs, in);
check_unary<Scalar, op_pnegate>(in, test::negate<Scalar>, bits);
check_unary<Scalar, op_pabs>(
in, [](Scalar x) { return Eigen::internal::pabs(x); }, bits);
check_binary<Scalar, op_psub>(pairs, test::REF_SUB<Scalar>, bits);
binary_inputs<Scalar> nonzero = pairs;
for (Scalar& y : nonzero.b) {
if (y == Scalar(0)) y = Scalar(1);
}
check_binary<Scalar, op_pdiv>(nonzero, test::REF_DIV<Scalar>, bits);
check_binary<Scalar, op_pandnot>(
pairs, [](Scalar x, Scalar y) { return Eigen::internal::pandnot(x, y); }, bits);
}
void packetmath_gpu_bool_fallback() {
binary_inputs<bool> pairs;
for (int k = 0; k < 1 << 10; ++k) pairs.push(Eigen::internal::random<bool>(), Eigen::internal::random<bool>());
// std::vector<bool> has no data(): copy lane by lane.
Buffer<bool> in(pairs.size());
for (int k = 0; k < pairs.size(); ++k) in[k] = pairs.a[k];
check_scalar_fallback_common<bool>(pairs, in);
}
void packetmath_gpu_bfloat16_fallback() {
using Scalar = Eigen::bfloat16;
const compare_bits<Scalar> bits{true};
const std::vector<float> specials = special_values<float>();
binary_inputs<Scalar> pairs;
for (float x : specials) {
for (float y : specials) pairs.push(Scalar(x), Scalar(y));
}
for (int k = 0; k < 1 << 12; ++k) {
pairs.push(Scalar(Eigen::internal::random<float>(-4.0f, 4.0f)),
Scalar(Eigen::internal::random<float>(-4.0f, 4.0f)));
}
const Buffer<Scalar> in = Eigen::Map<const Buffer<Scalar>>(pairs.a.data(), pairs.size());
check_scalar_fallback_common<Scalar>(pairs, in);
check_unary<Scalar, op_pnegate>(in, test::negate<Scalar>, bits);
check_unary<Scalar, op_pabs>(
in, [](Scalar x) { return Eigen::internal::pabs(x); }, bits);
check_binary<Scalar, op_psub>(pairs, test::REF_SUB<Scalar>, bits);
check_binary<Scalar, op_pdiv>(pairs, test::REF_DIV<Scalar>, bits);
// A one-ulp sqrtf error can cross a bfloat16 rounding boundary.
check_unary<Scalar, op_psqrt>(
in, [](Scalar x) { return Eigen::internal::psqrt(x); }, compare_ulps<Scalar>{kSqrtFloatUlps});
check_unary<Scalar, op_pfloor>(
in, [](Scalar x) { return Eigen::internal::pfloor(x); }, bits);
}
template <typename Scalar>
void packetmath_gpu_preinterpret() {
using Bits = typename Eigen::numext::get_integer_by_size<sizeof(Scalar)>::signed_type;
const int kSize = packet_layout<typename packet_traits<Scalar>::type>::kSize;
const Buffer<Scalar> in = unary_inputs<Scalar>(kSize, 1 << 10);
Buffer<Bits> out(in.size());
out.setZero();
run_on_gpu(preinterpret_scalar_kernel<Scalar, Bits>(), int(in.size()), in, out);
for (Index k = 0; k < in.size(); ++k) {
VERIFY_IS_EQUAL(out[k], Eigen::numext::bit_cast<Bits>(in[k]));
}
}
// Compiled in the host pass as well as the device pass: with EIGEN_USE_GPU defined, packet_traits<float>::type is
// float4 in both, so an expression reaching psign, a comparison or a bit operation has to compile on the host too.
// It did not before those operations moved out of the device-only block.
void host_pass_instantiation() {
Eigen::Array<float, 32, 1> a = Eigen::Array<float, 32, 1>::Random();
a(0) = std::numeric_limits<float>::quiet_NaN();
const Eigen::Array<float, 32, 1> s = a.sign();
const Eigen::Array<bool, 32, 1> nans = a.isNaN();
const Eigen::Array<float, 32, 1> clamped = a.cwiseMax(0.0f).cwiseMin(1.0f);
VERIFY((Eigen::numext::isnan)(s(0)));
VERIFY(nans(0));
VERIFY(clamped(1) >= 0.0f && clamped(1) <= 1.0f);
}
} // namespace
EIGEN_DECLARE_TEST(packetmath_gpu) {
ei_test_init_gpu();
CALL_SUBTEST_1(host_pass_instantiation());
CALL_SUBTEST_1(packetmath_gpu_real_core<float>());
CALL_SUBTEST_2(packetmath_gpu_real_math<float>());
CALL_SUBTEST_3(packetmath_gpu_real_core<double>());
CALL_SUBTEST_4(packetmath_gpu_real_math<double>());
CALL_SUBTEST_5(packetmath_gpu_half_core());
CALL_SUBTEST_6(packetmath_gpu_half_math());
CALL_SUBTEST_7(packetmath_gpu_integer_fallback<int32_t>());
CALL_SUBTEST_7(packetmath_gpu_integer_fallback<int64_t>());
CALL_SUBTEST_7(packetmath_gpu_integer_fallback<uint8_t>());
CALL_SUBTEST_7(packetmath_gpu_bool_fallback());
CALL_SUBTEST_7(packetmath_gpu_bfloat16_fallback());
CALL_SUBTEST_7(packetmath_gpu_preinterpret<float>());
CALL_SUBTEST_7(packetmath_gpu_preinterpret<double>());
}