[for the future] Maybe use int_fast16_t instead of int16_t in the VM?

[jpellegrini]

Hi @egallesio !

I'm not sure if it would actually make a difference, but... "Theoretically", it could make the VM faster. The "fast" size for int_fast16_t is not the same as int16_t, at least in two architectures that I use.

#include <stdio.h>
#include <stdint.h>
int main() {
  printf("int_fast8_t  %ld -> %ld\n", sizeof(int8_t),  sizeof(int_fast8_t));
  printf("int_fast16_t %ld -> %ld\n", sizeof(int16_t), sizeof(int_fast16_t));
  printf("int_fast32_t %ld -> %ld\n", sizeof(int32_t), sizeof(int_fast32_t));
  printf("int_fast64_t %ld -> %ld\n", sizeof(int64_t), sizeof(int_fast64_t));
}

On an amd64 machine I get

int_fast8_t  1 -> 1
int_fast16_t 2 -> 8
int_fast32_t 4 -> 8
int_fast64_t 8 -> 8

On a mipsel wireless router,

int_fast8_t  1 -> 1
int_fast16_t 2 -> 4
int_fast32_t 4 -> 4
int_fast64_t 8 -> 8

Of course, I tried to just change the types and... STklos crashed when compiling (Well, I supposed it wouldn't be as simple as that).

But theoretically, the bytecode files wouldn't need to be changed. We can store the bytes as usual, and read them into int_fast16_t variables instead of int16_t...

Anyway -- not urgent, of course!