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p++;		p++;
len--;		len--;
}		}
}		}

/** If flag is true, set r equal to a; otherwise leave it. Constant-time. Both r and a must be initialized and non-negative.*/		/** If flag is true, set r equal to a; otherwise leave it. Constant-time. Both r and a must be initialized and non-negative.*/
static SECP256K1_INLINE void secp256k1_int_cmov(int r, const int a, int flag) {		static SECP256K1_INLINE void secp256k1_int_cmov(int r, const int a, int flag) {
unsigned int mask0, mask1, r_masked, a_masked;		unsigned int mask0, mask1, r_masked, a_masked;
		/* Access flag with a volatile-qualified lvalue.
		This prevents clang from figuring out (after inlining) that flag can
		take only be 0 or 1, which leads to variable time code. */
		volatile int vflag = flag;

/* Casting a negative int to unsigned and back to int is implementation defined behavior */		/* Casting a negative int to unsigned and back to int is implementation defined behavior */
VERIFY_CHECK(r >= 0 && a >= 0);		VERIFY_CHECK(r >= 0 && a >= 0);

mask0 = (unsigned int)flag + ~0u;		mask0 = (unsigned int)vflag + ~0u;
mask1 = ~mask0;		mask1 = ~mask0;
r_masked = ((unsigned int)*r & mask0);		r_masked = ((unsigned int)*r & mask0);
a_masked = ((unsigned int)*a & mask1);		a_masked = ((unsigned int)*a & mask1);

*r = (int)(r_masked \| a_masked);		*r = (int)(r_masked \| a_masked);
}		}

#endif /* SECP256K1_UTIL_H */		#endif /* SECP256K1_UTIL_H */