__builtin_arm_uqsub8 is only available on gcc newer or equal than 10.
Checked on arm-linux-gnueabihf built with gcc 9.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
/* Use unsigned saturated subtraction from 1 in each byte.
That leaves 1 for every byte that was zero. */
op_t ones = repeat_bytes (0x01);
+#if __GNUC_PREREQ (10, 0)
return __builtin_arm_uqsub8 (ones, x);
+#else
+ op_t ret;
+ asm ("uqsub8 %0,%1,%2" : "=r"(ret) : "r"(ones), "r"(x));
+ return ret;
+#endif
}
/* Identify bytes that are equal between X1 and X2. */