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[/] [openrisc/] [trunk/] [gnu-old/] [newlib-1.17.0/] [newlib/] [libc/] [machine/] [xscale/] [strlen.c] - Rev 820
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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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