Replacing pcmestri on Arm

This function is used to compare the elements in str1 and str2 based on the model rules (EQUAL_EACH and NEG_POLARITY), and return the index value of the first different element.

For details about the intrinsic function corresponding to pcmpestri, see Intrinsics Guide.

• Code on x86:

  template<int MODE>
  static inline int SSE4_cmpestri(__m128i str1, int len1, __m128i str2, int len2) {
    int result;
    __asm__ __volatile__("pcmpestri %5, %2, %1": "=c"(result) : "x"(str1), "xm"(str2), "a"(len1), "d"(len2), "i"(MODE) : "cc");
    return result;
  }

• Alternative for Kunpeng processors:

  #include <arm_neon.h>
  template<int MODE>
  static inline int SSE4_cmpestri(int32x4_t str1, int len1, int32x4_t str2, int len2) {
  __oword a, b;
  a.m128i = str1;
  b.m128i = str2;
      int len_s, len_l;
  if (len1 > len2) {
  len_s = len2;
  len_l = len1;
      } else {
  len_s = len1;
  len_l = len2;
    }
  int result;
  int i;
      // Replacement mode in this example: STRCMP_MODE =
  // PCMPSTR_EQUAL_EACH | PCMPSTR_UBYTE_OPS | PCMPSTR_NEG_POLARITY
      for(i = 0; i < len_s; i++) {
  if (a.m128i_u8[i] == b.m128i_u8[i]) {
  break;
  }
  }
  result = i;
  if (result == len_s) result = len_l;
  return result;
  }