1/*
 2 * String handling functions.
 3 *
 4 * Copyright IBM Corp. 2012
 5 */
 6
 7#include <linux/linkage.h>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 8
 9/*
10 * memset implementation
11 *
12 * This code corresponds to the C construct below. We do distinguish
13 * between clearing (c == 0) and setting a memory array (c != 0) simply
14 * because nearly all memset invocations in the kernel clear memory and
15 * the xc instruction is preferred in such cases.
16 *
17 * void *memset(void *s, int c, size_t n)
18 * {
19 *	if (likely(c == 0))
20 *		return __builtin_memset(s, 0, n);
21 *	return __builtin_memset(s, c, n);
22 * }
23 */
24ENTRY(memset)
25	ltgr	%r4,%r4
26	bzr	%r14
27	ltgr	%r3,%r3
28	jnz	.Lmemset_fill
29	aghi	%r4,-1
30	srlg	%r3,%r4,8
31	ltgr	%r3,%r3
32	lgr	%r1,%r2
33	jz	.Lmemset_clear_rest
34.Lmemset_clear_loop:
35	xc	0(256,%r1),0(%r1)
36	la	%r1,256(%r1)
37	brctg	%r3,.Lmemset_clear_loop
38.Lmemset_clear_rest:
39	larl	%r3,.Lmemset_xc
40	ex	%r4,0(%r3)
41	br	%r14
42.Lmemset_fill:
43	stc	%r3,0(%r2)
44	cghi	%r4,1
45	lgr	%r1,%r2
46	ber	%r14
47	aghi	%r4,-2
48	srlg	%r3,%r4,8
49	ltgr	%r3,%r3
50	jz	.Lmemset_fill_rest
51.Lmemset_fill_loop:
52	mvc	1(256,%r1),0(%r1)
53	la	%r1,256(%r1)
54	brctg	%r3,.Lmemset_fill_loop
55.Lmemset_fill_rest:
56	larl	%r3,.Lmemset_mvc
57	ex	%r4,0(%r3)
58	br	%r14
59.Lmemset_xc:
60	xc	0(1,%r1),0(%r1)
61.Lmemset_mvc:
62	mvc	1(1,%r1),0(%r1)
 
63
64/*
65 * memcpy implementation
66 *
67 * void *memcpy(void *dest, const void *src, size_t n)
68 */
69ENTRY(memcpy)
70	ltgr	%r4,%r4
71	bzr	%r14
72	aghi	%r4,-1
73	srlg	%r5,%r4,8
74	ltgr	%r5,%r5
75	lgr	%r1,%r2
76	jnz	.Lmemcpy_loop
77.Lmemcpy_rest:
78	larl	%r5,.Lmemcpy_mvc
79	ex	%r4,0(%r5)
80	br	%r14
81.Lmemcpy_loop:
82	mvc	0(256,%r1),0(%r3)
83	la	%r1,256(%r1)
84	la	%r3,256(%r3)
85	brctg	%r5,.Lmemcpy_loop
86	j	.Lmemcpy_rest
87.Lmemcpy_mvc:
88	mvc	0(1,%r1),0(%r3)

  1/*
  2 * String handling functions.
  3 *
  4 * Copyright IBM Corp. 2012
  5 */
  6
  7#include <linux/linkage.h>
  8#include <asm/export.h>
  9
 10/*
 11 * void *memmove(void *dest, const void *src, size_t n)
 12 */
 13ENTRY(memmove)
 14	ltgr	%r4,%r4
 15	lgr	%r1,%r2
 16	bzr	%r14
 17	clgr	%r2,%r3
 18	jnh	.Lmemmove_forward
 19	la	%r5,0(%r4,%r3)
 20	clgr	%r2,%r5
 21	jl	.Lmemmove_reverse
 22.Lmemmove_forward:
 23	aghi	%r4,-1
 24	srlg	%r0,%r4,8
 25	ltgr	%r0,%r0
 26	jz	.Lmemmove_rest
 27.Lmemmove_loop:
 28	mvc	0(256,%r1),0(%r3)
 29	la	%r1,256(%r1)
 30	la	%r3,256(%r3)
 31	brctg	%r0,.Lmemmove_loop
 32.Lmemmove_rest:
 33	larl	%r5,.Lmemmove_mvc
 34	ex	%r4,0(%r5)
 35	br	%r14
 36.Lmemmove_reverse:
 37	aghi	%r4,-1
 38.Lmemmove_reverse_loop:
 39	ic	%r0,0(%r4,%r3)
 40	stc	%r0,0(%r4,%r1)
 41	brctg	%r4,.Lmemmove_reverse_loop
 42	ic	%r0,0(%r4,%r3)
 43	stc	%r0,0(%r4,%r1)
 44	br	%r14
 45.Lmemmove_mvc:
 46	mvc	0(1,%r1),0(%r3)
 47EXPORT_SYMBOL(memmove)
 48
 49/*
 50 * memset implementation
 51 *
 52 * This code corresponds to the C construct below. We do distinguish
 53 * between clearing (c == 0) and setting a memory array (c != 0) simply
 54 * because nearly all memset invocations in the kernel clear memory and
 55 * the xc instruction is preferred in such cases.
 56 *
 57 * void *memset(void *s, int c, size_t n)
 58 * {
 59 *	if (likely(c == 0))
 60 *		return __builtin_memset(s, 0, n);
 61 *	return __builtin_memset(s, c, n);
 62 * }
 63 */
 64ENTRY(memset)
 65	ltgr	%r4,%r4
 66	bzr	%r14
 67	ltgr	%r3,%r3
 68	jnz	.Lmemset_fill
 69	aghi	%r4,-1
 70	srlg	%r3,%r4,8
 71	ltgr	%r3,%r3
 72	lgr	%r1,%r2
 73	jz	.Lmemset_clear_rest
 74.Lmemset_clear_loop:
 75	xc	0(256,%r1),0(%r1)
 76	la	%r1,256(%r1)
 77	brctg	%r3,.Lmemset_clear_loop
 78.Lmemset_clear_rest:
 79	larl	%r3,.Lmemset_xc
 80	ex	%r4,0(%r3)
 81	br	%r14
 82.Lmemset_fill:
 83	stc	%r3,0(%r2)
 84	cghi	%r4,1
 85	lgr	%r1,%r2
 86	ber	%r14
 87	aghi	%r4,-2
 88	srlg	%r3,%r4,8
 89	ltgr	%r3,%r3
 90	jz	.Lmemset_fill_rest
 91.Lmemset_fill_loop:
 92	mvc	1(256,%r1),0(%r1)
 93	la	%r1,256(%r1)
 94	brctg	%r3,.Lmemset_fill_loop
 95.Lmemset_fill_rest:
 96	larl	%r3,.Lmemset_mvc
 97	ex	%r4,0(%r3)
 98	br	%r14
 99.Lmemset_xc:
100	xc	0(1,%r1),0(%r1)
101.Lmemset_mvc:
102	mvc	1(1,%r1),0(%r1)
103EXPORT_SYMBOL(memset)
104
105/*
106 * memcpy implementation
107 *
108 * void *memcpy(void *dest, const void *src, size_t n)
109 */
110ENTRY(memcpy)
111	ltgr	%r4,%r4
112	bzr	%r14
113	aghi	%r4,-1
114	srlg	%r5,%r4,8
115	ltgr	%r5,%r5
116	lgr	%r1,%r2
117	jnz	.Lmemcpy_loop
118.Lmemcpy_rest:
119	larl	%r5,.Lmemcpy_mvc
120	ex	%r4,0(%r5)
121	br	%r14
122.Lmemcpy_loop:
123	mvc	0(256,%r1),0(%r3)
124	la	%r1,256(%r1)
125	la	%r3,256(%r3)
126	brctg	%r5,.Lmemcpy_loop
127	j	.Lmemcpy_rest
128.Lmemcpy_mvc:
129	mvc	0(1,%r1),0(%r3)
130EXPORT_SYMBOL(memcpy)