/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_NOPS_H
#define _ASM_X86_NOPS_H
#include <asm/asm.h>
/*
* Define nops for use with alternative() and for tracing.
*/
#ifndef CONFIG_64BIT
/*
* Generic 32bit nops from GAS:
*
* 1: nop
* 2: movl %esi,%esi
* 3: leal 0x0(%esi),%esi
* 4: leal 0x0(%esi,%eiz,1),%esi
* 5: leal %ds:0x0(%esi,%eiz,1),%esi
* 6: leal 0x0(%esi),%esi
* 7: leal 0x0(%esi,%eiz,1),%esi
* 8: leal %ds:0x0(%esi,%eiz,1),%esi
*
* Except 5 and 8, which are DS prefixed 4 and 7 resp, where GAS would emit 2
* nop instructions.
*/
#define BYTES_NOP1 0x90
#define BYTES_NOP2 0x89,0xf6
#define BYTES_NOP3 0x8d,0x76,0x00
#define BYTES_NOP4 0x8d,0x74,0x26,0x00
#define BYTES_NOP5 0x3e,BYTES_NOP4
#define BYTES_NOP6 0x8d,0xb6,0x00,0x00,0x00,0x00
#define BYTES_NOP7 0x8d,0xb4,0x26,0x00,0x00,0x00,0x00
#define BYTES_NOP8 0x3e,BYTES_NOP7
#define ASM_NOP_MAX 8
#else
/*
* Generic 64bit nops from GAS:
*
* 1: nop
* 2: osp nop
* 3: nopl (%eax)
* 4: nopl 0x00(%eax)
* 5: nopl 0x00(%eax,%eax,1)
* 6: osp nopl 0x00(%eax,%eax,1)
* 7: nopl 0x00000000(%eax)
* 8: nopl 0x00000000(%eax,%eax,1)
* 9: cs nopl 0x00000000(%eax,%eax,1)
* 10: osp cs nopl 0x00000000(%eax,%eax,1)
* 11: osp osp cs nopl 0x00000000(%eax,%eax,1)
*/
#define BYTES_NOP1 0x90
#define BYTES_NOP2 0x66,BYTES_NOP1
#define BYTES_NOP3 0x0f,0x1f,0x00
#define BYTES_NOP4 0x0f,0x1f,0x40,0x00
#define BYTES_NOP5 0x0f,0x1f,0x44,0x00,0x00
#define BYTES_NOP6 0x66,BYTES_NOP5
#define BYTES_NOP7 0x0f,0x1f,0x80,0x00,0x00,0x00,0x00
#define BYTES_NOP8 0x0f,0x1f,0x84,0x00,0x00,0x00,0x00,0x00
#define BYTES_NOP9 0x2e,BYTES_NOP8
#define BYTES_NOP10 0x66,BYTES_NOP9
#define BYTES_NOP11 0x66,BYTES_NOP10
#define ASM_NOP9 _ASM_BYTES(BYTES_NOP9)
#define ASM_NOP10 _ASM_BYTES(BYTES_NOP10)
#define ASM_NOP11 _ASM_BYTES(BYTES_NOP11)
#define ASM_NOP_MAX 11
#endif /* CONFIG_64BIT */
#define ASM_NOP1 _ASM_BYTES(BYTES_NOP1)
#define ASM_NOP2 _ASM_BYTES(BYTES_NOP2)
#define ASM_NOP3 _ASM_BYTES(BYTES_NOP3)
#define ASM_NOP4 _ASM_BYTES(BYTES_NOP4)
#define ASM_NOP5 _ASM_BYTES(BYTES_NOP5)
#define ASM_NOP6 _ASM_BYTES(BYTES_NOP6)
#define ASM_NOP7 _ASM_BYTES(BYTES_NOP7)
#define ASM_NOP8 _ASM_BYTES(BYTES_NOP8)
#ifndef __ASSEMBLY__
extern const unsigned char * const x86_nops[];
#endif
#endif /* _ASM_X86_NOPS_H */
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