LXR linux/include/asm-x86/nops.h

   1#ifndef _ASM_NOPS_H
   2#define _ASM_NOPS_H 1
   3
   4/* Define nops for use with alternative() */
   5
   6/* generic versions from gas
   7   1: nop
   8   2: movl %esi,%esi
   9   3: leal 0x00(%esi),%esi
  10   4: leal 0x00(,%esi,1),%esi
  11   6: leal 0x00000000(%esi),%esi
  12   7: leal 0x00000000(,%esi,1),%esi
  13*/
  14#define GENERIC_NOP1 ".byte 0x90\n"
  15#define GENERIC_NOP2 ".byte 0x89,0xf6\n"
  16#define GENERIC_NOP3 ".byte 0x8d,0x76,0x00\n"
  17#define GENERIC_NOP4 ".byte 0x8d,0x74,0x26,0x00\n"
  18#define GENERIC_NOP5 GENERIC_NOP1 GENERIC_NOP4
  19#define GENERIC_NOP6 ".byte 0x8d,0xb6,0x00,0x00,0x00,0x00\n"
  20#define GENERIC_NOP7 ".byte 0x8d,0xb4,0x26,0x00,0x00,0x00,0x00\n"
  21#define GENERIC_NOP8 GENERIC_NOP1 GENERIC_NOP7
  22
  23/* Opteron 64bit nops
  24   1: nop
  25   2: osp nop
  26   3: osp osp nop
  27   4: osp osp osp nop
  28*/
  29#define K8_NOP1 GENERIC_NOP1
  30#define K8_NOP2 ".byte 0x66,0x90\n"
  31#define K8_NOP3 ".byte 0x66,0x66,0x90\n"
  32#define K8_NOP4 ".byte 0x66,0x66,0x66,0x90\n"
  33#define K8_NOP5 K8_NOP3 K8_NOP2
  34#define K8_NOP6 K8_NOP3 K8_NOP3
  35#define K8_NOP7 K8_NOP4 K8_NOP3
  36#define K8_NOP8 K8_NOP4 K8_NOP4
  37
  38/* K7 nops
  39   uses eax dependencies (arbitary choice)
  40   1: nop
  41   2: movl %eax,%eax
  42   3: leal (,%eax,1),%eax
  43   4: leal 0x00(,%eax,1),%eax
  44   6: leal 0x00000000(%eax),%eax
  45   7: leal 0x00000000(,%eax,1),%eax
  46*/
  47#define K7_NOP1 GENERIC_NOP1
  48#define K7_NOP2 ".byte 0x8b,0xc0\n"
  49#define K7_NOP3 ".byte 0x8d,0x04,0x20\n"
  50#define K7_NOP4 ".byte 0x8d,0x44,0x20,0x00\n"
  51#define K7_NOP5 K7_NOP4 ASM_NOP1
  52#define K7_NOP6 ".byte 0x8d,0x80,0,0,0,0\n"
  53#define K7_NOP7 ".byte 0x8D,0x04,0x05,0,0,0,0\n"
  54#define K7_NOP8 K7_NOP7 ASM_NOP1
  55
  56/* P6 nops
  57   uses eax dependencies (Intel-recommended choice)
  58   1: nop
  59   2: osp nop
  60   3: nopl (%eax)
  61   4: nopl 0x00(%eax)
  62   5: nopl 0x00(%eax,%eax,1)
  63   6: osp nopl 0x00(%eax,%eax,1)
  64   7: nopl 0x00000000(%eax)
  65   8: nopl 0x00000000(%eax,%eax,1)
  66*/
  67#define P6_NOP1 GENERIC_NOP1
  68#define P6_NOP2 ".byte 0x66,0x90\n"
  69#define P6_NOP3 ".byte 0x0f,0x1f,0x00\n"
  70#define P6_NOP4 ".byte 0x0f,0x1f,0x40,0\n"
  71#define P6_NOP5 ".byte 0x0f,0x1f,0x44,0x00,0\n"
  72#define P6_NOP6 ".byte 0x66,0x0f,0x1f,0x44,0x00,0\n"
  73#define P6_NOP7 ".byte 0x0f,0x1f,0x80,0,0,0,0\n"
  74#define P6_NOP8 ".byte 0x0f,0x1f,0x84,0x00,0,0,0,0\n"
  75
  76#if defined(CONFIG_MK7)
  77#define ASM_NOP1 K7_NOP1
  78#define ASM_NOP2 K7_NOP2
  79#define ASM_NOP3 K7_NOP3
  80#define ASM_NOP4 K7_NOP4
  81#define ASM_NOP5 K7_NOP5
  82#define ASM_NOP6 K7_NOP6
  83#define ASM_NOP7 K7_NOP7
  84#define ASM_NOP8 K7_NOP8
  85#elif defined(CONFIG_X86_P6_NOP)
  86#define ASM_NOP1 P6_NOP1
  87#define ASM_NOP2 P6_NOP2
  88#define ASM_NOP3 P6_NOP3
  89#define ASM_NOP4 P6_NOP4
  90#define ASM_NOP5 P6_NOP5
  91#define ASM_NOP6 P6_NOP6
  92#define ASM_NOP7 P6_NOP7
  93#define ASM_NOP8 P6_NOP8
  94#elif defined(CONFIG_X86_64)
  95#define ASM_NOP1 K8_NOP1
  96#define ASM_NOP2 K8_NOP2
  97#define ASM_NOP3 K8_NOP3
  98#define ASM_NOP4 K8_NOP4
  99#define ASM_NOP5 K8_NOP5
 100#define ASM_NOP6 K8_NOP6
 101#define ASM_NOP7 K8_NOP7
 102#define ASM_NOP8 K8_NOP8
 103#else
 104#define ASM_NOP1 GENERIC_NOP1
 105#define ASM_NOP2 GENERIC_NOP2
 106#define ASM_NOP3 GENERIC_NOP3
 107#define ASM_NOP4 GENERIC_NOP4
 108#define ASM_NOP5 GENERIC_NOP5
 109#define ASM_NOP6 GENERIC_NOP6
 110#define ASM_NOP7 GENERIC_NOP7
 111#define ASM_NOP8 GENERIC_NOP8
 112#endif
 113
 114#define ASM_NOP_MAX 8
 115
 116#endif
 117