newlib-cygwin/newlib/libc/machine/xscale/strcpy.c

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#if defined __thumb__
#include "../../string/strcpy.c"
#else
#include <string.h>
#include "xscale.h"
char *
strcpy (char *dest, const char *src)
{
char *dest0 = dest;
asm (PRELOADSTR ("%0") : : "r" (src));
#ifndef __OPTIMIZE_SIZE__
if (((long)src & 3) == ((long)dest & 3))
{
/* Skip unaligned part. */
while ((long)src & 3)
{
if (! (*dest++ = *src++))
return dest0;
}
/* Load two constants:
R4 = 0xfefefeff [ == ~(0x80808080 << 1) ]
R5 = 0x80808080 */
asm ("mov r5, #0x80\n\
ldr r1, [%1, #0]\n\
add r5, r5, #0x8000\n\
add r5, r5, r5, lsl #16\n\
mvn r4, r5, lsl #1\n\
\n\
add r3, r1, r5\n\
bic r3, r3, r1\n\
ands r2, r3, r4\n\
bne 1f\n\
0:\n\
ldr r3, [%1, #0]\n\
ldr r1, [%1, #4]!\n\
" PRELOADSTR("%1") "\n\
str r3, [%0], #4\n\
add r2, r1, r4\n\
bic r2, r2, r1\n\
ands r3, r2, r5\n\
beq 0b\n\
1:"
: "=&r" (dest), "=&r" (src)
: "0" (dest), "1" (src)
: "r1", "r2", "r3", "r4", "r5", "memory", "cc");
}
#endif
while (*dest++ = *src++)
asm (PRELOADSTR ("%0") : : "r" (src));
return dest0;
}
#endif