mirror of
https://github.com/autc04/Retro68.git
synced 2024-12-12 11:29:30 +00:00
108 lines
1.9 KiB
C
108 lines
1.9 KiB
C
|
#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
|