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[/] [openrisc/] [trunk/] [gnu-stable/] [newlib-1.18.0/] [newlib/] [libc/] [machine/] [xscale/] [strcmp.c] - Rev 207
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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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