Program Listing for File ApplyGeneratorIsingZZ.hpp¶
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// Copyright 2023 Xanadu Quantum Technologies Inc.
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#pragma once
#include "AVXConceptType.hpp"
#include "AVXUtil.hpp"
#include "BitUtil.hpp"
#include "Permutation.hpp"
#include "Util.hpp"
#include <complex>
namespace Pennylane::LightningQubit::Gates::AVXCommon {
template <typename PrecisionT, std::size_t packed_size>
struct ApplyGeneratorIsingZZ {
using Precision = PrecisionT;
using PrecisionAVXConcept =
typename AVXConcept<PrecisionT, packed_size>::Type;
constexpr static std::size_t packed_size_ = packed_size;
constexpr static bool symmetric = true;
template <size_t rev_wire0, std::size_t rev_wire1>
static auto applyInternalInternal(std::complex<PrecisionT> *arr,
std::size_t num_qubits,
[[maybe_unused]] bool adj) -> PrecisionT {
using namespace Permutation;
const auto signs = toParity<Precision, packed_size>([](size_t idx) {
return (((idx >> rev_wire0) & std::size_t{1U}) ^
((idx >> rev_wire1) & std::size_t{1U}));
});
PL_LOOP_PARALLEL(1)
for (size_t n = 0; n < exp2(num_qubits); n += packed_size / 2) {
const auto v = PrecisionAVXConcept::load(arr + n);
PrecisionAVXConcept::store(arr + n, signs * v);
}
return -static_cast<PrecisionT>(
0.5); // NOLINT(readability-magic-numbers)
}
template <size_t min_rev_wire>
static auto applyInternalExternal(std::complex<PrecisionT> *arr,
std::size_t num_qubits,
std::size_t max_rev_wire,
[[maybe_unused]] bool adj) -> PrecisionT {
using namespace Permutation;
const std::size_t max_rev_wire_shift =
(static_cast<std::size_t>(1U) << max_rev_wire);
const std::size_t max_wire_parity = fillTrailingOnes(max_rev_wire);
const std::size_t max_wire_parity_inv =
fillLeadingOnes(max_rev_wire + 1);
const auto sign0 = internalParity<Precision, packed_size>(min_rev_wire);
const auto sign1 =
-internalParity<Precision, packed_size>(min_rev_wire);
PL_LOOP_PARALLEL(1)
for (size_t k = 0; k < exp2(num_qubits - 1); k += packed_size / 2) {
const std::size_t i0 =
((k << 1U) & max_wire_parity_inv) | (max_wire_parity & k);
const std::size_t i1 = i0 | max_rev_wire_shift;
const auto v0 = PrecisionAVXConcept::load(arr + i0);
const auto v1 = PrecisionAVXConcept::load(arr + i1);
PrecisionAVXConcept::store(arr + i0, v0 * sign0);
PrecisionAVXConcept::store(arr + i1, v1 * sign1);
}
return -static_cast<PrecisionT>(
0.5); // NOLINT(readability-magic-numbers)
}
static auto applyExternalExternal(std::complex<PrecisionT> *arr,
const std::size_t num_qubits,
const std::size_t rev_wire0,
const std::size_t rev_wire1,
[[maybe_unused]] bool adj) -> PrecisionT {
using namespace Permutation;
const std::size_t rev_wire0_shift = static_cast<std::size_t>(1U)
<< rev_wire0;
const std::size_t rev_wire1_shift = static_cast<std::size_t>(1U)
<< rev_wire1;
const std::size_t rev_wire_min = std::min(rev_wire0, rev_wire1);
const std::size_t rev_wire_max = std::max(rev_wire0, rev_wire1);
const std::size_t parity_low = fillTrailingOnes(rev_wire_min);
const std::size_t parity_high = fillLeadingOnes(rev_wire_max + 1);
const std::size_t parity_middle =
fillLeadingOnes(rev_wire_min + 1) & fillTrailingOnes(rev_wire_max);
PL_LOOP_PARALLEL(1)
for (size_t k = 0; k < exp2(num_qubits - 2); k += packed_size / 2) {
const std::size_t i00 = ((k << 2U) & parity_high) |
((k << 1U) & parity_middle) |
(k & parity_low);
const std::size_t i10 = i00 | rev_wire1_shift;
const std::size_t i01 = i00 | rev_wire0_shift;
const auto v01 = PrecisionAVXConcept::load(arr + i01); // 01
const auto v10 = PrecisionAVXConcept::load(arr + i10); // 10
PrecisionAVXConcept::store(arr + i01, -v01);
PrecisionAVXConcept::store(arr + i10, -v10);
}
return -static_cast<PrecisionT>(
0.5); // NOLINT(readability-magic-numbers)
}
};
} // namespace Pennylane::LightningQubit::Gates::AVXCommon
api/program_listing_file_pennylane_lightning_core_src_simulators_lightning_qubit_gates_cpu_kernels_avx_common_ApplyGeneratorIsingZZ.hpp
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