dwarf2.h

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#ifndef _ASM_X86_DWARF2_H
#define _ASM_X86_DWARF2_H

#ifndef __ASSEMBLY__
#warning "asm/dwarf2.h should be only included in pure assembly files"
#endif

/*
 * Macros for dwarf2 CFI unwind table entries.
 * See "as.info" for details on these pseudo ops. Unfortunately
 * they are only supported in very new binutils, so define them
 * away for older version.
 */

#ifdef CONFIG_AS_CFI

#define CFI_STARTPROC       .cfi_startproc
#define CFI_ENDPROC     .cfi_endproc
#define CFI_DEF_CFA     .cfi_def_cfa
#define CFI_DEF_CFA_REGISTER    .cfi_def_cfa_register
#define CFI_DEF_CFA_OFFSET  .cfi_def_cfa_offset
#define CFI_ADJUST_CFA_OFFSET   .cfi_adjust_cfa_offset
#define CFI_OFFSET      .cfi_offset
#define CFI_REL_OFFSET      .cfi_rel_offset
#define CFI_REGISTER        .cfi_register
#define CFI_RESTORE     .cfi_restore
#define CFI_REMEMBER_STATE  .cfi_remember_state
#define CFI_RESTORE_STATE   .cfi_restore_state
#define CFI_UNDEFINED       .cfi_undefined
#define CFI_ESCAPE      .cfi_escape

#ifdef CONFIG_AS_CFI_SIGNAL_FRAME
#define CFI_SIGNAL_FRAME    .cfi_signal_frame
#else
#define CFI_SIGNAL_FRAME
#endif

#if defined(CONFIG_AS_CFI_SECTIONS) && defined(__ASSEMBLY__)
    /*
     * Emit CFI data in .debug_frame sections, not .eh_frame sections.
     * The latter we currently just discard since we don't do DWARF
     * unwinding at runtime.  So only the offline DWARF information is
     * useful to anyone.  Note we should not use this directive if this
     * file is used in the vDSO assembly, or if vmlinux.lds.S gets
     * changed so it doesn't discard .eh_frame.
     */
    .cfi_sections .debug_frame
#endif

#else

/*
 * Due to the structure of pre-exisiting code, don't use assembler line
 * comment character # to ignore the arguments. Instead, use a dummy macro.
 */
.macro cfi_ignore a=0, b=0, c=0, d=0
.endm

#define CFI_STARTPROC       cfi_ignore
#define CFI_ENDPROC     cfi_ignore
#define CFI_DEF_CFA     cfi_ignore
#define CFI_DEF_CFA_REGISTER    cfi_ignore
#define CFI_DEF_CFA_OFFSET  cfi_ignore
#define CFI_ADJUST_CFA_OFFSET   cfi_ignore
#define CFI_OFFSET      cfi_ignore
#define CFI_REL_OFFSET      cfi_ignore
#define CFI_REGISTER        cfi_ignore
#define CFI_RESTORE     cfi_ignore
#define CFI_REMEMBER_STATE  cfi_ignore
#define CFI_RESTORE_STATE   cfi_ignore
#define CFI_UNDEFINED       cfi_ignore
#define CFI_ESCAPE      cfi_ignore
#define CFI_SIGNAL_FRAME    cfi_ignore

#endif

/*
 * An attempt to make CFI annotations more or less
 * correct and shorter. It is implied that you know
 * what you're doing if you use them.
 */
#ifdef __ASSEMBLY__
#ifdef CONFIG_X86_64
    .macro pushq_cfi reg
    pushq \reg
    CFI_ADJUST_CFA_OFFSET 8
    .endm

    .macro popq_cfi reg
    popq \reg
    CFI_ADJUST_CFA_OFFSET -8
    .endm

    .macro pushfq_cfi
    pushfq
    CFI_ADJUST_CFA_OFFSET 8
    .endm

    .macro popfq_cfi
    popfq
    CFI_ADJUST_CFA_OFFSET -8
    .endm

    .macro movq_cfi reg offset=0
    movq %\reg, \offset(%rsp)
    CFI_REL_OFFSET \reg, \offset
    .endm

    .macro movq_cfi_restore offset reg
    movq \offset(%rsp), %\reg
    CFI_RESTORE \reg
    .endm
#else 
    .macro pushl_cfi reg
    pushl \reg
    CFI_ADJUST_CFA_OFFSET 4
    .endm

    .macro popl_cfi reg
    popl \reg
    CFI_ADJUST_CFA_OFFSET -4
    .endm

    .macro pushfl_cfi
    pushfl
    CFI_ADJUST_CFA_OFFSET 4
    .endm

    .macro popfl_cfi
    popfl
    CFI_ADJUST_CFA_OFFSET -4
    .endm

    .macro movl_cfi reg offset=0
    movl %\reg, \offset(%esp)
    CFI_REL_OFFSET \reg, \offset
    .endm

    .macro movl_cfi_restore offset reg
    movl \offset(%esp), %\reg
    CFI_RESTORE \reg
    .endm
#endif 
#endif /*__ASSEMBLY__*/

#endif /* _ASM_X86_DWARF2_H */