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#if defined __thumb__
#include "../../string/strcmp.c"
#else
#include <string.h>
#include "xscale.h"
int
strcmp (const char *s1, const char *s2)
{
asm (PRELOADSTR ("%0") : : "r" (s1));
asm (PRELOADSTR ("%0") : : "r" (s2));
#ifndef __OPTIMIZE_SIZE__
if (((long)s1 & 3) == ((long)s2 & 3))
{
int result;
/* Skip unaligned part. */
while ((long)s1 & 3)
{
if (*s1 == '\0' || *s1 != *s2)
goto out;
s1++;
s2++;
}
/* Load two constants:
lr = 0xfefefeff [ == ~(0x80808080 << 1) ]
ip = 0x80808080 */
asm (
"ldr r2, [%1, #0]\n\
ldr r3, [%2, #0]\n\
cmp r2, r3\n\
bne 2f\n\
\n\
mov ip, #0x80\n\
add ip, ip, #0x8000\n\
add ip, ip, ip, lsl #16\n\
mvn lr, ip, lsl #1\n\
\n\
0:\n\
ldr r2, [%1, #0]\n\
add r3, r2, lr\n\
bic r3, r3, r2\n\
tst r3, ip\n\
beq 1f\n\
mov %0, #0x0\n\
b 3f\n\
1:\n\
ldr r2, [%1, #4]!\n\
ldr r3, [%2, #4]!\n\
" PRELOADSTR("%1") "\n\
" PRELOADSTR("%2") "\n\
cmp r2, r3\n\
beq 0b"
/* The following part could be done in a C loop as well, but it needs
to be assembler to save some cycles in the case where the optimized
loop above finds the strings to be equal. */
"\n\
2:\n\
ldrb r2, [%1, #0]\n\
" PRELOADSTR("%1") "\n\
" PRELOADSTR("%2") "\n\
cmp r2, #0x0\n\
beq 1f\n\
ldrb r3, [%2, #0]\n\
cmp r2, r3\n\
bne 1f\n\
0:\n\
ldrb r3, [%1, #1]!\n\
add %2, %2, #1\n\
ands ip, r3, #0xff\n\
beq 1f\n\
ldrb r3, [%2]\n\
cmp ip, r3\n\
beq 0b\n\
1:\n\
ldrb lr, [%1, #0]\n\
ldrb ip, [%2, #0]\n\
rsb %0, ip, lr\n\
3:\n\
"
: "=r" (result), "=&r" (s1), "=&r" (s2)
: "1" (s1), "2" (s2)
: "lr", "ip", "r2", "r3", "cc");
return result;
}
#endif
while (*s1 != '\0' && *s1 == *s2)
{
asm (PRELOADSTR("%0") : : "r" (s1));
asm (PRELOADSTR("%0") : : "r" (s2));
s1++;
s2++;
}
out:
return (*(unsigned char *) s1) - (*(unsigned char *) s2);
}
#endif
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