The __builtin_arm_uqsub8 is an internal GCC builtin which might change
in future release (the correct way is to include "arm_acle.h" and use
__uqsub8 ()). Since not all compilers support it, just use the
inline assembler instead.
Checked on armv7a-linux-gnueabihf.
Reviewed-by: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
/* 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. */