[PATCH 3/3] resolv: Optimize inet_ntop

[Paul Eggert]

On 6/3/25 12:51, Adhemerval Zanella wrote:


> static inline char *put_uint8 (uint8_t word, char *tp)

Put the function name at the start of a line.

> +  intptr_t s = 1;

There should be no need for intptr_t; 'int' is good enough and clearer 
and should generate the same machine code.

> +      tp[2] = _itoa_lower_digits[word % 10];

Don't consult an array; just add '0'.

> +  if (word >= 100)
> ...
> +  if (word >= 10)

Since this is for performance, shouldn't the code avoid conditional 
branches? Something like the following, say:

   static inline char *
   put_uint8 (uint8_t word, char *tp)
   {
     *tp = '0' + word / 100;
     tp += 100 <= word;
     *tp = '0' + word / 10 % 10;
     tp += 10 <= word;
     *tp++ = '0' + word % 10;
     return tp;
   }

Alternatively, if we're going to have conditional branches, there is no 
need to test (word >= 100) if (word >= 10) is false.