/******************************************************************************

 * string.c

 *

 * These provide something for compiler-emitted string operations to link

 * against.

 */

#include <xen/lib.h>

void *(memcpy)(void *dest, const void *src, size_t n)

{

    long d0, d1, d2;

    asm volatile (

        "   rep ; movs"__OS" ; "

        "   mov %k4,%k3      ; "

        "   rep ; movsb        "

        : "=&c" (d0), "=&D" (d1), "=&S" (d2)

        : "0" (n/BYTES_PER_LONG), "r" (n%BYTES_PER_LONG), "1" (dest), "2" (src)

        : "memory" );

    return dest;

}

void *(memset)(void *s, int c, size_t n)

{

    long d0, d1;

    asm volatile (

        "rep stosb"

        : "=&c" (d0), "=&D" (d1)

        : "a" (c), "1" (s), "0" (n)

        : "memory");

    return s;

}

void *(memmove)(void *dest, const void *src, size_t n)

{

    long d0, d1, d2;

    if ( unlikely(!n) )

        return dest;

    if ( dest < src )

        return memcpy(dest, src, n);

    asm volatile (

        "   std         ; "

        "   rep movsb   ; "

        "   cld           "

        : "=&c" (d0), "=&S" (d1), "=&D" (d2)

        : "0" (n), "1" (n-1+(const char *)src), "2" (n-1+(char *)dest)

        : "memory");

    return dest;

}

/*

 * Local variables:

 * mode: C

 * c-file-style: "BSD"

 * c-basic-offset: 4

 * tab-width: 4

 * indent-tabs-mode: nil

 * End:

 */