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1#ifndef _ASM_X86_NOPS_H
2#define _ASM_X86_NOPS_H
3
4/* Define nops for use with alternative() */
5
6/* generic versions from gas
7 1: nop
8 the following instructions are NOT nops in 64-bit mode,
9 for 64-bit mode use K8 or P6 nops instead
10 2: movl %esi,%esi
11 3: leal 0x00(%esi),%esi
12 4: leal 0x00(,%esi,1),%esi
13 6: leal 0x00000000(%esi),%esi
14 7: leal 0x00000000(,%esi,1),%esi
15*/
16#define GENERIC_NOP1 ".byte 0x90\n"
17#define GENERIC_NOP2 ".byte 0x89,0xf6\n"
18#define GENERIC_NOP3 ".byte 0x8d,0x76,0x00\n"
19#define GENERIC_NOP4 ".byte 0x8d,0x74,0x26,0x00\n"
20#define GENERIC_NOP5 GENERIC_NOP1 GENERIC_NOP4
21#define GENERIC_NOP6 ".byte 0x8d,0xb6,0x00,0x00,0x00,0x00\n"
22#define GENERIC_NOP7 ".byte 0x8d,0xb4,0x26,0x00,0x00,0x00,0x00\n"
23#define GENERIC_NOP8 GENERIC_NOP1 GENERIC_NOP7
24
25/* Opteron 64bit nops
26 1: nop
27 2: osp nop
28 3: osp osp nop
29 4: osp osp osp nop
30*/
31#define K8_NOP1 GENERIC_NOP1
32#define K8_NOP2 ".byte 0x66,0x90\n"
33#define K8_NOP3 ".byte 0x66,0x66,0x90\n"
34#define K8_NOP4 ".byte 0x66,0x66,0x66,0x90\n"
35#define K8_NOP5 K8_NOP3 K8_NOP2
36#define K8_NOP6 K8_NOP3 K8_NOP3
37#define K8_NOP7 K8_NOP4 K8_NOP3
38#define K8_NOP8 K8_NOP4 K8_NOP4
39
40/* K7 nops
41 uses eax dependencies (arbitary choice)
42 1: nop
43 2: movl %eax,%eax
44 3: leal (,%eax,1),%eax
45 4: leal 0x00(,%eax,1),%eax
46 6: leal 0x00000000(%eax),%eax
47 7: leal 0x00000000(,%eax,1),%eax
48*/
49#define K7_NOP1 GENERIC_NOP1
50#define K7_NOP2 ".byte 0x8b,0xc0\n"
51#define K7_NOP3 ".byte 0x8d,0x04,0x20\n"
52#define K7_NOP4 ".byte 0x8d,0x44,0x20,0x00\n"
53#define K7_NOP5 K7_NOP4 ASM_NOP1
54#define K7_NOP6 ".byte 0x8d,0x80,0,0,0,0\n"
55#define K7_NOP7 ".byte 0x8D,0x04,0x05,0,0,0,0\n"
56#define K7_NOP8 K7_NOP7 ASM_NOP1
57
58/* P6 nops
59 uses eax dependencies (Intel-recommended choice)
60 1: nop
61 2: osp nop
62 3: nopl (%eax)
63 4: nopl 0x00(%eax)
64 5: nopl 0x00(%eax,%eax,1)
65 6: osp nopl 0x00(%eax,%eax,1)
66 7: nopl 0x00000000(%eax)
67 8: nopl 0x00000000(%eax,%eax,1)
68*/
69#define P6_NOP1 GENERIC_NOP1
70#define P6_NOP2 ".byte 0x66,0x90\n"
71#define P6_NOP3 ".byte 0x0f,0x1f,0x00\n"
72#define P6_NOP4 ".byte 0x0f,0x1f,0x40,0\n"
73#define P6_NOP5 ".byte 0x0f,0x1f,0x44,0x00,0\n"
74#define P6_NOP6 ".byte 0x66,0x0f,0x1f,0x44,0x00,0\n"
75#define P6_NOP7 ".byte 0x0f,0x1f,0x80,0,0,0,0\n"
76#define P6_NOP8 ".byte 0x0f,0x1f,0x84,0x00,0,0,0,0\n"
77
78#if defined(CONFIG_MK7)
79#define ASM_NOP1 K7_NOP1
80#define ASM_NOP2 K7_NOP2
81#define ASM_NOP3 K7_NOP3
82#define ASM_NOP4 K7_NOP4
83#define ASM_NOP5 K7_NOP5
84#define ASM_NOP6 K7_NOP6
85#define ASM_NOP7 K7_NOP7
86#define ASM_NOP8 K7_NOP8
87#elif defined(CONFIG_X86_P6_NOP)
88#define ASM_NOP1 P6_NOP1
89#define ASM_NOP2 P6_NOP2
90#define ASM_NOP3 P6_NOP3
91#define ASM_NOP4 P6_NOP4
92#define ASM_NOP5 P6_NOP5
93#define ASM_NOP6 P6_NOP6
94#define ASM_NOP7 P6_NOP7
95#define ASM_NOP8 P6_NOP8
96#elif defined(CONFIG_X86_64)
97#define ASM_NOP1 K8_NOP1
98#define ASM_NOP2 K8_NOP2
99#define ASM_NOP3 K8_NOP3
100#define ASM_NOP4 K8_NOP4
101#define ASM_NOP5 K8_NOP5
102#define ASM_NOP6 K8_NOP6
103#define ASM_NOP7 K8_NOP7
104#define ASM_NOP8 K8_NOP8
105#else
106#define ASM_NOP1 GENERIC_NOP1
107#define ASM_NOP2 GENERIC_NOP2
108#define ASM_NOP3 GENERIC_NOP3
109#define ASM_NOP4 GENERIC_NOP4
110#define ASM_NOP5 GENERIC_NOP5
111#define ASM_NOP6 GENERIC_NOP6
112#define ASM_NOP7 GENERIC_NOP7
113#define ASM_NOP8 GENERIC_NOP8
114#endif
115
116#define ASM_NOP_MAX 8
117
118#endif /* _ASM_X86_NOPS_H */