simdjson/src/arm64/stringparsing.h

#ifndef SIMDJSON_ARM64_STRINGPARSING_H
#define SIMDJSON_ARM64_STRINGPARSING_H

#include "simdjson.h"

#ifdef IS_ARM64

#include "jsoncharutils.h"
#include "arm64/simd.h"
#include "arm64/intrinsics.h"
#include "arm64/bitmanipulation.h"

namespace simdjson::arm64 {

using namespace simd;

// Holds backslashes and quotes locations.
struct parse_string_helper {
  uint32_t bs_bits;
  uint32_t quote_bits;
  static const uint32_t BYTES_PROCESSED = 32;
};

really_inline parse_string_helper find_bs_bits_and_quote_bits(const uint8_t *src, uint8_t *dst) {
  // this can read up to 31 bytes beyond the buffer size, but we require
  // SIMDJSON_PADDING of padding
  static_assert(SIMDJSON_PADDING >= (parse_string_helper::BYTES_PROCESSED - 1));
  simd8<uint8_t> v0(src);
  simd8<uint8_t> v1(src + sizeof(v0));
  v0.store(dst);
  v1.store(dst + sizeof(v0));

  // Getting a 64-bit bitmask is much cheaper than multiple 16-bit bitmasks on ARM; therefore, we
  // smash them together into a 64-byte mask and get the bitmask from there.
  uint64_t bs_and_quote = simd8x64<bool>(v0 == '\\', v1 == '\\', v0 == '"', v1 == '"').to_bitmask();
  return {
    static_cast<uint32_t>(bs_and_quote),      // bs_bits
    static_cast<uint32_t>(bs_and_quote >> 32) // quote_bits
  };
}

#include "generic/stringparsing.h"

}
// namespace simdjson::amd64

#endif // IS_ARM64

#endif // SIMDJSON_ARM64_STRINGPARSING_H