#ifndef SIMDJSON_ICELAKE_BITMANIPULATION_H #define SIMDJSON_ICELAKE_BITMANIPULATION_H #ifndef SIMDJSON_CONDITIONAL_INCLUDE #include "simdjson/icelake/base.h" #include "simdjson/icelake/intrinsics.h" #endif // SIMDJSON_CONDITIONAL_INCLUDE namespace simdjson { namespace icelake { namespace { // We sometimes call trailing_zero on inputs that are zero, // but the algorithms do not end up using the returned value. // Sadly, sanitizers are not smart enough to figure it out. SIMDJSON_NO_SANITIZE_UNDEFINED // This function can be used safely even if not all bytes have been // initialized. // See issue https://github.com/simdjson/simdjson/issues/1965 SIMDJSON_NO_SANITIZE_MEMORY simdjson_inline int trailing_zeroes(uint64_t input_num) { #if SIMDJSON_REGULAR_VISUAL_STUDIO return (int)_tzcnt_u64(input_num); #else // SIMDJSON_REGULAR_VISUAL_STUDIO //////// // You might expect the next line to be equivalent to // return (int)_tzcnt_u64(input_num); // but the generated code differs and might be less efficient? //////// return __builtin_ctzll(input_num); #endif // SIMDJSON_REGULAR_VISUAL_STUDIO } /* result might be undefined when input_num is zero */ simdjson_inline uint64_t clear_lowest_bit(uint64_t input_num) { return _blsr_u64(input_num); } /* result might be undefined when input_num is zero */ simdjson_inline int leading_zeroes(uint64_t input_num) { return int(_lzcnt_u64(input_num)); } #if SIMDJSON_REGULAR_VISUAL_STUDIO simdjson_inline unsigned __int64 count_ones(uint64_t input_num) { // note: we do not support legacy 32-bit Windows return __popcnt64(input_num);// Visual Studio wants two underscores } #else simdjson_inline long long int count_ones(uint64_t input_num) { return _popcnt64(input_num); } #endif simdjson_inline bool add_overflow(uint64_t value1, uint64_t value2, uint64_t *result) { #if SIMDJSON_REGULAR_VISUAL_STUDIO return _addcarry_u64(0, value1, value2, reinterpret_cast(result)); #else return __builtin_uaddll_overflow(value1, value2, reinterpret_cast(result)); #endif } } // unnamed namespace } // namespace icelake } // namespace simdjson #endif // SIMDJSON_ICELAKE_BITMANIPULATION_H