diff options
Diffstat (limited to 'common/dynamic_bitarray.h')
-rw-r--r-- | common/dynamic_bitarray.h | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/common/dynamic_bitarray.h b/common/dynamic_bitarray.h new file mode 100644 index 00000000..7a7b2bf9 --- /dev/null +++ b/common/dynamic_bitarray.h @@ -0,0 +1,82 @@ +/* + * nextpnr -- Next Generation Place and Route + * + * Copyright (C) 2021 Symbiflow Authors + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + * + */ + +#include <cstdint> +#include <limits> +#include <vector> + +// This class implements a simple dynamic bitarray, backed by some resizable +// random access storage. The default is to use a std::vector<uint8_t>. + +#ifndef DYNAMIC_BITARRAY_H +#define DYNAMIC_BITARRAY_H + +namespace nextpnr { + +template <typename Storage = std::vector<uint8_t>> class DynamicBitarray +{ + public: + static_assert(!std::numeric_limits<typename Storage::value_type>::is_signed, "Storage must be unsigned!"); + + void fill(bool value) + { + std::fill(storage.begin(), storage.end(), value ? std::numeric_limits<typename Storage::value_type>::max() : 0); + } + + constexpr size_t bits_per_value() const + { + return sizeof(typename Storage::value_type) * std::numeric_limits<typename Storage::value_type>::digits; + } + + bool get(size_t bit) const + { + size_t element_index = bit / bits_per_value(); + size_t bit_offset = bit % bits_per_value(); + + auto element = storage.at(element_index); + return (element & (1 << bit_offset)) != 0; + } + + void set(size_t bit, bool value) + { + size_t element_index = bit / bits_per_value(); + size_t bit_offset = bit % bits_per_value(); + + if (value) { + storage.at(element_index) |= (1 << bit_offset); + } else { + storage.at(element_index) &= ~(1 << bit_offset); + } + } + + void resize(size_t number_bits) + { + size_t required_storage = (number_bits + bits_per_value()) / bits_per_value(); + storage.resize(required_storage); + } + + size_t size() const { return storage.size() * bits_per_value(); } + + private: + Storage storage; +}; + +}; // namespace nextpnr + +#endif /* DYNAMIC_BITARRAY_H */ |