xref: /OK3568_Linux_fs/kernel/include/vdso/math64.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun #ifndef __VDSO_MATH64_H
3*4882a593Smuzhiyun #define __VDSO_MATH64_H
4*4882a593Smuzhiyun 
5*4882a593Smuzhiyun static __always_inline u32
__iter_div_u64_rem(u64 dividend,u32 divisor,u64 * remainder)6*4882a593Smuzhiyun __iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder)
7*4882a593Smuzhiyun {
8*4882a593Smuzhiyun 	u32 ret = 0;
9*4882a593Smuzhiyun 
10*4882a593Smuzhiyun 	while (dividend >= divisor) {
11*4882a593Smuzhiyun 		/* The following asm() prevents the compiler from
12*4882a593Smuzhiyun 		   optimising this loop into a modulo operation.  */
13*4882a593Smuzhiyun 		asm("" : "+rm"(dividend));
14*4882a593Smuzhiyun 
15*4882a593Smuzhiyun 		dividend -= divisor;
16*4882a593Smuzhiyun 		ret++;
17*4882a593Smuzhiyun 	}
18*4882a593Smuzhiyun 
19*4882a593Smuzhiyun 	*remainder = dividend;
20*4882a593Smuzhiyun 
21*4882a593Smuzhiyun 	return ret;
22*4882a593Smuzhiyun }
23*4882a593Smuzhiyun 
24*4882a593Smuzhiyun #endif /* __VDSO_MATH64_H */
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