🚀 go-pugleaf

/* Fill the buffer pointed to by s, with c, n times.  */
 
inline void Memset (void *s, int c, int n){
   asm (
        "movl    %1, %%edi\n"
        "movl    %2, %%eax\n"
        "movl    %3, %%ecx\n"
        "movb    %%al, %%ah\n"
        "movl    %%eax, %%edx\n"
        "shll    $16, %%eax\n"
        "movw    %%dx, %%ax\n"
        "shrl    $2, %%ecx\n"
        "rep\n"
        "stosl\n"
        "movl    %3, %%ecx\n" 
        "andl    $3, %%ecx\n"
        "rep\n"
        "stosb\n"
        : "g" (s), "g" (c), "g" (n)
        : "edi", "eax", "ecx", "edx"
   );
}
        This is a non-working memset function.  If I add a local variable
int x, and add ': "=g" (x)' before the other ':' lines it will compile and
work so long as I don't compile with -O or -O2.  (btw: on 486dx33 8MB under
OS2-2.0).  I have no idea or docs, only another single function to try to
work out the format from.  Please, why won't it work when compiled with -O2
I looked at the asm output and it compiled to a seperate function that was
little more than begin-return.
and what do I have to put in so it don't need to have temporary variables.
I *need* it to be fast, and before u cry 'but its only 1 squillonth of a sec'
i reckon every little bit counts. (and it does)
        If there is some sort of doc file on this could someone please send
&/| post it please.  The function body itself i lifted from memset.s in my
lib source, so there aint nothing wrong with that.

                                                        Kingsley Turner