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#if defined __thumb__
#include "../../string/memset.c"
#else
#include <string.h>
#include "xscale.h"
void *
memset (void *dst, int c, size_t len)
{
int dummy;
asm volatile ("tst %0, #0x3"
#ifndef __OPTIMIZE_SIZE__
"\n\
beq 1f\n\
b 2f\n\
0:\n\
strb %1, [%0], #1\n\
tst %0, #0x3\n\
beq 1f\n\
2:\n\
movs r3, %2\n\
sub %2, %2, #1\n\
bne 0b\n\
# At this point we know that %2 == len == -1 (since the SUB has already taken\n\
# place). If we fall through to the 1: label (as the code used to do), the\n\
# CMP will detect this negative value and branch to the 2: label. This will\n\
# test %2 again, but this time against 0. The test will fail and the loop\n\
# at 2: will go on for (almost) ever. Hence the explicit branch to the end\n\
# of the hand written assembly code.\n\
b 4f\n\
1:\n\
cmp %2, #0x3\n\
bls 2f\n\
and %1, %1, #0xff\n\
orr lr, %1, %1, asl #8\n\
cmp %2, #0xf\n\
orr lr, lr, lr, asl #16\n\
bls 1f\n\
mov r3, lr\n\
mov r4, lr\n\
mov r5, lr\n\
0:\n\
sub %2, %2, #16\n\
stmia %0!, { r3, r4, r5, lr }\n\
cmp %2, #0xf\n\
bhi 0b\n\
1:\n\
cmp %2, #0x7\n\
bls 1f\n\
mov r3, lr\n\
0:\n\
sub %2, %2, #8\n\
stmia %0!, { r3, lr }\n\
cmp %2, #0x7\n\
bhi 0b\n\
1:\n\
cmp %2, #0x3\n\
bls 2f\n\
0:\n\
sub %2, %2, #4\n\
str lr, [%0], #4\n\
cmp %2, #0x3\n\
bhi 0b\n\
"
#endif /* !__OPTIMIZE_SIZE__ */
"\n\
2:\n\
movs r3, %2\n\
sub %2, %2, #1\n\
beq 4f\n\
0:\n\
movs r3, %2\n\
sub %2, %2, #1\n\
strb %1, [%0], #1\n\
bne 0b\n\
4:"
: "=&r" (dummy), "=&r" (c), "=&r" (len)
: "0" (dst), "1" (c), "2" (len)
: "memory", "r3", "r4", "r5", "lr");
return dst;
}
#endif
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