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#if defined __thumb__ || defined(PREFER_SIZE_OVER_SPEED) || defined(__OPTIMIZE_SIZE__)
#include "../../string/strlen.c"
#else
#include <string.h>
#include "xscale.h"
size_t
strlen (const char *str)
{
_CONST char *start = str;
/* Skip unaligned part. */
if ((long)str & 3)
{
str--;
do
{
if (*++str == '\0')
goto out;
}
while ((long)str & 3);
}
/* Load two constants:
R4 = 0xfefefeff [ == ~(0x80808080 << 1) ]
R5 = 0x80808080 */
asm ("mov r5, #0x80\n\
add r5, r5, #0x8000\n\
add r5, r5, r5, lsl #16\n\
mvn r4, r5, lsl #1\n\
"
#if defined __ARM_ARCH_5__ || defined __ARM_ARCH_5T__ || defined __ARM_ARCH_5E__ || defined __ARM_ARCH_5TE__
" tst %0, #0x7\n\
ldreqd r6, [%0]\n\
beq 1f\n\
ldr r2, [%0]\n\
add r3, r2, r4\n\
bic r3, r3, r2\n\
ands r2, r3, r5\n\
bne 2f\n\
sub %0, %0, #4\n\
\n\
0:\n\
ldrd r6, [%0, #8]!\n\
"
PRELOADSTR ("%0")
"\n\
1:\n\
add r3, r6, r4\n\
add r2, r7, r4\n\
bic r3, r3, r6\n\
bic r2, r2, r7\n\
and r3, r3, r5\n\
and r2, r2, r5\n\
orrs r3, r2, r3\n\
beq 0b\n\
"
#else
" sub %0, %0, #4\n\
\n\
0:\n\
ldr r6, [%0, #4]!\n\
"
PRELOADSTR ("%0")
"\n\
add r3, r6, r4\n\
bic r3, r3, r6\n\
ands r3, r3, r5\n\
beq 0b\n\
"
#endif /* __ARM_ARCH_5[T][E]__ */
"\n\
2:\n\
ldrb r3, [%0]\n\
cmp r3, #0x0\n\
beq 1f\n\
\n\
0:\n\
ldrb r3, [%0, #1]!\n\
"
PRELOADSTR ("%0")
"\n\
cmp r3, #0x0\n\
bne 0b\n\
1:\n\
"
: "=r" (str) : "0" (str) : "r2", "r3", "r4", "r5", "r6", "r7");
out:
return str - start;
}
#endif
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