Re: egcs-problem 1.0.2

[hjl@lucon.org (H.J. Lu)]

> This is the "linux asm" problem that I haven't been able to look at
> for the last month or so due to personal and company commitments.
> 
> Basically there's a couple problems:
> 
>   * The linux x86 asm for strstr is totally bogus.

Does the code below make sense?

> 
>   * GCC does not issue a warning/error when it encouters the bogus
>   asm and instead generates incorrect code.

Agreed. I don't think it is too hard to issue an error.


Thanks.


-- 
H.J. Lu (hjl@gnu.org)
----
extern inline char * strstr(const char * cs,const char * ct)
{
register char * __res;
__asm__ __volatile__(
	"cld\n\t" \
	"movl %4,%%edi\n\t"
	"repne\n\t"
	"scasb\n\t"
	"notl %%ecx\n\t"
	"decl %%ecx\n\t"
	"movl %%ecx,%%edx\n"
	"1:\tmovl %4,%%edi\n\t"
	"movl %%esi,%%eax\n\t"
	"movl %%edx,%%ecx\n\t"
	"repe\n\t"
	"cmpsb\n\t"
	"je 2f\n\t"
	"xchgl %%eax,%%esi\n\t"
	"incl %%esi\n\t"
	"cmpb $0,-1(%%eax)\n\t"
	"jne 1b\n\t"
	"xorl %%eax,%%eax\n\t"
	"2:"
	:"=a" (__res):"0" (0),"c" (0xffffffff),"S" (cs),"m" (ct)
	:"cx","dx","di","si");
return __res;
}

int count_substring_matches(char **haystacks, char **needles)
{
        int hits=0, i, j;
        for(i=0; haystacks[i]; i++) {
                for(j=0; needles[j]; j++) {
                        if (strstr(haystacks[i], needles[j])) hits++;
                }
        }
        return hits;
}

main ()
{
  char * haystacks [] = {"foobar", 0};
  char * needles  [] = {"foo", 0};

  if (count_substring_matches (haystacks, needles ) != 1)
    abort ();

  return 0;
}