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gcc/libiberty/memcmp.c

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/* memcmp -- compare two memory regions.
This function is in the public domain. */
/*
@deftypefn Supplemental int memcmp (const void *@var{x}, const void *@var{y}, size_t @var{count})
Compares the first @var{count} bytes of two areas of memory. Returns
zero if they are the same, a value less than zero if @var{x} is
lexically less than @var{y}, or a value greater than zero if @var{x}
is lexically greater than @var{y}. Note that lexical order is determined
as if comparing unsigned char arrays.
@end deftypefn
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*/
#include <ansidecl.h>
#ifdef ANSI_PROTOTYPES
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#include <stddef.h>
#else
#define size_t unsigned long
#endif
int
memcmp (str1, str2, count)
const PTR str1;
const PTR str2;
size_t count;
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{
register const unsigned char *s1 = (const unsigned char*)str1;
register const unsigned char *s2 = (const unsigned char*)str2;
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while (count-- > 0)
{
if (*s1++ != *s2++)
return s1[-1] < s2[-1] ? -1 : 1;
}
return 0;
}