xref: /OK3568_Linux_fs/kernel/lib/ashrdi3.c (revision 4882a59341e53eb6f0b4789bf948001014eff981) 
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  */
4*4882a593Smuzhiyun 
5*4882a593Smuzhiyun #include <linux/export.h>
6*4882a593Smuzhiyun 
7*4882a593Smuzhiyun #include <linux/libgcc.h>
8*4882a593Smuzhiyun 
__ashrdi3(long long u,word_type b)9*4882a593Smuzhiyun long long notrace __ashrdi3(long long u, word_type b)
10*4882a593Smuzhiyun {
11*4882a593Smuzhiyun 	DWunion uu, w;
12*4882a593Smuzhiyun 	word_type bm;
13*4882a593Smuzhiyun 
14*4882a593Smuzhiyun 	if (b == 0)
15*4882a593Smuzhiyun 		return u;
16*4882a593Smuzhiyun 
17*4882a593Smuzhiyun 	uu.ll = u;
18*4882a593Smuzhiyun 	bm = 32 - b;
19*4882a593Smuzhiyun 
20*4882a593Smuzhiyun 	if (bm <= 0) {
21*4882a593Smuzhiyun 		/* w.s.high = 1..1 or 0..0 */
22*4882a593Smuzhiyun 		w.s.high =
23*4882a593Smuzhiyun 		    uu.s.high >> 31;
24*4882a593Smuzhiyun 		w.s.low = uu.s.high >> -bm;
25*4882a593Smuzhiyun 	} else {
26*4882a593Smuzhiyun 		const unsigned int carries = (unsigned int) uu.s.high << bm;
27*4882a593Smuzhiyun 
28*4882a593Smuzhiyun 		w.s.high = uu.s.high >> b;
29*4882a593Smuzhiyun 		w.s.low = ((unsigned int) uu.s.low >> b) | carries;
30*4882a593Smuzhiyun 	}
31*4882a593Smuzhiyun 
32*4882a593Smuzhiyun 	return w.ll;
33*4882a593Smuzhiyun }
34*4882a593Smuzhiyun EXPORT_SYMBOL(__ashrdi3);
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