// Copyright 2025 Google LLC

//

// 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.

#ifndef SOURCE_UTIL_SPAN_H_

#define SOURCE_UTIL_SPAN_H_

#include <cstddef>

#include <iterator>

#include <type_traits>

namespace spvtools {

namespace utils {

// Implement a subset of the C++20 std::span, using at most C++17 functionality.

// Replace this when SPIRV-Tools can use C++20.

template <class T>

class Span {

 public:

  using element_type = T;

  using value_type = std::remove_cv_t<T>;

  using size_type = std::size_t;

  using difference_type = std::ptrdiff_t;

  using pointer = T*;

  using const_pointer = const T*;

  using reference = T&;

  using const_reference = const T&;

  using iterator = T*;

  using const_iterator = const T*;

  Span() {}

Unexecuted instantiation: spvtools::utils::Span<spv_operand_type_t const>::Span()

Unexecuted instantiation: spvtools::utils::Span<char const>::Span()

Unexecuted instantiation: spvtools::utils::Span<spvtools::utils::IndexRange<unsigned int, unsigned int, unsigned int> const>::Span()

Unexecuted instantiation: spvtools::utils::Span<spv::Capability const>::Span()

Unexecuted instantiation: spvtools::utils::Span<spvtools::Extension const>::Span()

Unexecuted instantiation: spvtools::utils::Span<spvtools::OperandDesc const>::Span()

Unexecuted instantiation: table2.cpp:spvtools::utils::Span<spvtools::(anonymous namespace)::NameIndex const>::Span()

Unexecuted instantiation: spvtools::utils::Span<spvtools::ExtInstDesc const>::Span()

  Span(iterator first, size_type count) : first_(first), count_(count) {}

spvtools::utils::Span<spv_operand_type_t const>::Span(spv_operand_type_t const*, unsigned long)

Line

Count

Source

42

1.09M

  Span(iterator first, size_type count) : first_(first), count_(count) {}

spvtools::utils::Span<char const>::Span(char const*, unsigned long)

Line

Count

Source

42

144k

  Span(iterator first, size_type count) : first_(first), count_(count) {}

Unexecuted instantiation: spvtools::utils::Span<spvtools::utils::IndexRange<unsigned int, unsigned int, unsigned int> const>::Span(spvtools::utils::IndexRange<unsigned int, unsigned int, unsigned int> const*, unsigned long)

spvtools::utils::Span<spv::Capability const>::Span(spv::Capability const*, unsigned long)

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Source

42

517k

  Span(iterator first, size_type count) : first_(first), count_(count) {}

spvtools::utils::Span<spvtools::Extension const>::Span(spvtools::Extension const*, unsigned long)

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Source

42

449k

  Span(iterator first, size_type count) : first_(first), count_(count) {}

spvtools::utils::Span<spvtools::OperandDesc const>::Span(spvtools::OperandDesc const*, unsigned long)

Line

Count

Source

42

325k

  Span(iterator first, size_type count) : first_(first), count_(count) {}

Unexecuted instantiation: table2.cpp:spvtools::utils::Span<spvtools::(anonymous namespace)::NameIndex const>::Span(spvtools::(anonymous namespace)::NameIndex const*, unsigned long)

spvtools::utils::Span<spvtools::ExtInstDesc const>::Span(spvtools::ExtInstDesc const*, unsigned long)

Line

Count

Source

42

8.45k

  Span(iterator first, size_type count) : first_(first), count_(count) {}

  iterator begin() const { return first_; }

spvtools::utils::Span<spv::Capability const>::begin() const

Line

Count

Source

44

276k

  iterator begin() const { return first_; }

spvtools::utils::Span<spvtools::OperandDesc const>::begin() const

Line

Count

Source

44

325k

  iterator begin() const { return first_; }

Unexecuted instantiation: table2.cpp:spvtools::utils::Span<spvtools::(anonymous namespace)::NameIndex const>::begin() const

spvtools::utils::Span<spvtools::ExtInstDesc const>::begin() const

Line

Count

Source

44

8.45k

  iterator begin() const { return first_; }

spvtools::utils::Span<spvtools::Extension const>::begin() const

Line

Count

Source

44

223k

  iterator begin() const { return first_; }

  iterator end() const { return first_ ? first_ + count_ : nullptr; }

spvtools::utils::Span<spvtools::OperandDesc const>::end() const

Line

Count

Source

45

651k

  iterator end() const { return first_ ? first_ + count_ : nullptr; }

Unexecuted instantiation: table2.cpp:spvtools::utils::Span<spvtools::(anonymous namespace)::NameIndex const>::end() const

spvtools::utils::Span<spvtools::ExtInstDesc const>::end() const

Line

Count

Source

45

16.9k

  iterator end() const { return first_ ? first_ + count_ : nullptr; }

spvtools::utils::Span<spvtools::Extension const>::end() const

Line

Count

Source

45

223k

  iterator end() const { return first_ ? first_ + count_ : nullptr; }

Unexecuted instantiation: spvtools::utils::Span<spv::Capability const>::end() const

  const_iterator cbegin() const { return first_; }

  const_iterator cend() const { return first_ ? first_ + count_ : nullptr; }

  size_type size() const { return count_; }

spvtools::utils::Span<spv::Capability const>::size() const

Line

Count

Source

49

280k

  size_type size() const { return count_; }

spvtools::utils::Span<spv_operand_type_t const>::size() const

Line

Count

Source

49

1.09M

  size_type size() const { return count_; }

  size_type size_bytes() const { return count_ * sizeof(T); }

  bool empty() const { return first_ == nullptr || count_ == 0; }

  reference front() const { return *first_; }

  reference back() const { return *(first_ + count_ - 1); }

  pointer data() const { return first_; }

spvtools::utils::Span<char const>::data() const

Line

Count

Source

55

144k

  pointer data() const { return first_; }

spvtools::utils::Span<spvtools::Extension const>::data() const

Line

Count

Source

55

2.79k

  pointer data() const { return first_; }

spvtools::utils::Span<spv::Capability const>::data() const

Line

Count

Source

55

8.23k

  pointer data() const { return first_; }

  reference operator[](size_type idx) const { return first_[idx]; }

  Span<T> subspan(size_type offset) const {

    if (count_ > offset) {

      return Span(first_ + offset, count_ - offset);

    }

    return Span<T>();

  }

 private:

  T* first_ = nullptr;

  size_type count_ = 0;

};

}  // namespace utils

}  // namespace spvtools

#endif  // SOURCE_UTIL_SPAN_H_