Finding quote pairs with PCLMULQDQ
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
really_inline uint64_t find_quote_mask_and_bits( | |
__m256i input_lo, __m256i input_hi, uint64_t odd_ends, | |
uint64_t &prev_iter_inside_quote, uint64_t "e_bits) { | |
quote_bits = | |
cmp_mask_against_input(input_lo, input_hi, _mm256_set1_epi8('"')); | |
quote_bits = quote_bits & ~odd_ends; | |
uint64_t quote_mask = _mm_cvtsi128_si64(_mm_clmulepi64_si128( | |
_mm_set_epi64x(0ULL, quote_bits), _mm_set1_epi8(0xFF), 0)); | |
quote_mask ^= prev_iter_inside_quote; | |
// right shift of a signed value expected to be well-defined and standard | |
// compliant as of C++20, | |
// John Regher from Utah U. says this is fine code | |
prev_iter_inside_quote = | |
static_cast<uint64_t>(static_cast<int64_t>(quote_mask) >> 63); | |
return quote_mask; | |
} |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment