1. C++ / Говнокод #2355

    +63.4

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    /* This construction seems to be more optimiser friendly.
       (without it gcc does the isDIGIT test and the *s - '0' separately)
       With it gcc on arm is managing 6 instructions (6 cycles) per digit.
       In theory the optimiser could deduce how far to unroll the loop
       before checking for overflow.  */
    if (++s < send) {
      int digit = *s - '0';
      if (digit >= 0 && digit <= 9) {
        value = value * 10 + digit;
        if (++s < send) {
          digit = *s - '0';
          if (digit >= 0 && digit <= 9) {
            value = value * 10 + digit;
            if (++s < send) {
              digit = *s - '0';
              if (digit >= 0 && digit <= 9) {
                value = value * 10 + digit;
		        if (++s < send) {
                  digit = *s - '0';
                  if (digit >= 0 && digit <= 9) {
                    value = value * 10 + digit;
                    if (++s < send) {
                      digit = *s - '0';
                      if (digit >= 0 && digit <= 9) {
                        value = value * 10 + digit;
                        if (++s < send) {
                          digit = *s - '0';
                          if (digit >= 0 && digit <= 9) {
                            value = value * 10 + digit;
                            if (++s < send) {
                              digit = *s - '0';
                              if (digit >= 0 && digit <= 9) {
                                value = value * 10 + digit;
                                if (++s < send) {
                                  digit = *s - '0';
                                  if (digit >= 0 && digit <= 9) {
                                    value = value * 10 + digit;
                                    if (++s < send) {
                                      /* Now got 9 digits, so need to check
                                         each time for overflow.  */
                                      digit = *s - '0';
                                      while (digit >= 0 && digit <= 9
                                             && (value < max_div_10
                                                 || (value == max_div_10
                                                     && digit <= max_mod_10))) {
                                        value = value * 10 + digit;
                                        if (++s < send)
                                          digit = *s - '0';
                                        else
                                          break;
                                      }
                                      if (digit >= 0 && digit <= 9
                                          && (s < send)) {
                                        /* value overflowed.
                                           skip the remaining digits, don't
                                           worry about setting *valuep.  */
                                        do {
                                          s++;
                                        } while (s < send && isDIGIT(*s));
                                        numtype |=
                                          IS_NUMBER_GREATER_THAN_UV_MAX;
                                        goto skip_value;
                                      }
                                    }
                                  }
				 }
                              }
                            }
                          }
                        }
                      }
                    }
                  }
                }
              }
            }
          }
	 }
      }
    }

    Проверка числа в Perl-модуле. Судя по всему стояла задача оптимизировать под что-то.

    Запостил: Thomas_55, 30 Декабря 2009

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