dwarf.h

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/*
 * Copyright (C) 2009 Matt Fleming <[email protected]>
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 */
#ifndef __ASM_SH_DWARF_H
#define __ASM_SH_DWARF_H

#ifdef CONFIG_DWARF_UNWINDER

/*
 * DWARF expression operations
 */
#define DW_OP_addr  0x03
#define DW_OP_deref 0x06
#define DW_OP_const1u   0x08
#define DW_OP_const1s   0x09
#define DW_OP_const2u   0x0a
#define DW_OP_const2s   0x0b
#define DW_OP_const4u   0x0c
#define DW_OP_const4s   0x0d
#define DW_OP_const8u   0x0e
#define DW_OP_const8s   0x0f
#define DW_OP_constu    0x10
#define DW_OP_consts    0x11
#define DW_OP_dup   0x12
#define DW_OP_drop  0x13
#define DW_OP_over  0x14
#define DW_OP_pick  0x15
#define DW_OP_swap  0x16
#define DW_OP_rot   0x17
#define DW_OP_xderef    0x18
#define DW_OP_abs   0x19
#define DW_OP_and   0x1a
#define DW_OP_div   0x1b
#define DW_OP_minus 0x1c
#define DW_OP_mod   0x1d
#define DW_OP_mul   0x1e
#define DW_OP_neg   0x1f
#define DW_OP_not   0x20
#define DW_OP_or    0x21
#define DW_OP_plus  0x22
#define DW_OP_plus_uconst   0x23
#define DW_OP_shl   0x24
#define DW_OP_shr   0x25
#define DW_OP_shra  0x26
#define DW_OP_xor   0x27
#define DW_OP_skip  0x2f
#define DW_OP_bra   0x28
#define DW_OP_eq    0x29
#define DW_OP_ge    0x2a
#define DW_OP_gt    0x2b
#define DW_OP_le    0x2c
#define DW_OP_lt    0x2d
#define DW_OP_ne    0x2e
#define DW_OP_lit0  0x30
#define DW_OP_lit1  0x31
#define DW_OP_lit2  0x32
#define DW_OP_lit3  0x33
#define DW_OP_lit4  0x34
#define DW_OP_lit5  0x35
#define DW_OP_lit6  0x36
#define DW_OP_lit7  0x37
#define DW_OP_lit8  0x38
#define DW_OP_lit9  0x39
#define DW_OP_lit10 0x3a
#define DW_OP_lit11 0x3b
#define DW_OP_lit12 0x3c
#define DW_OP_lit13 0x3d
#define DW_OP_lit14 0x3e
#define DW_OP_lit15 0x3f
#define DW_OP_lit16 0x40
#define DW_OP_lit17 0x41
#define DW_OP_lit18 0x42
#define DW_OP_lit19 0x43
#define DW_OP_lit20 0x44
#define DW_OP_lit21 0x45
#define DW_OP_lit22 0x46
#define DW_OP_lit23 0x47
#define DW_OP_lit24 0x48
#define DW_OP_lit25 0x49
#define DW_OP_lit26 0x4a
#define DW_OP_lit27 0x4b
#define DW_OP_lit28 0x4c
#define DW_OP_lit29 0x4d
#define DW_OP_lit30 0x4e
#define DW_OP_lit31 0x4f
#define DW_OP_reg0  0x50
#define DW_OP_reg1  0x51
#define DW_OP_reg2  0x52
#define DW_OP_reg3  0x53
#define DW_OP_reg4  0x54
#define DW_OP_reg5  0x55
#define DW_OP_reg6  0x56
#define DW_OP_reg7  0x57
#define DW_OP_reg8  0x58
#define DW_OP_reg9  0x59
#define DW_OP_reg10 0x5a
#define DW_OP_reg11 0x5b
#define DW_OP_reg12 0x5c
#define DW_OP_reg13 0x5d
#define DW_OP_reg14 0x5e
#define DW_OP_reg15 0x5f
#define DW_OP_reg16 0x60
#define DW_OP_reg17 0x61
#define DW_OP_reg18 0x62
#define DW_OP_reg19 0x63
#define DW_OP_reg20 0x64
#define DW_OP_reg21 0x65
#define DW_OP_reg22 0x66
#define DW_OP_reg23 0x67
#define DW_OP_reg24 0x68
#define DW_OP_reg25 0x69
#define DW_OP_reg26 0x6a
#define DW_OP_reg27 0x6b
#define DW_OP_reg28 0x6c
#define DW_OP_reg29 0x6d
#define DW_OP_reg30 0x6e
#define DW_OP_reg31 0x6f
#define DW_OP_breg0 0x70
#define DW_OP_breg1 0x71
#define DW_OP_breg2 0x72
#define DW_OP_breg3 0x73
#define DW_OP_breg4 0x74
#define DW_OP_breg5 0x75
#define DW_OP_breg6 0x76
#define DW_OP_breg7 0x77
#define DW_OP_breg8 0x78
#define DW_OP_breg9 0x79
#define DW_OP_breg10    0x7a
#define DW_OP_breg11    0x7b
#define DW_OP_breg12    0x7c
#define DW_OP_breg13    0x7d
#define DW_OP_breg14    0x7e
#define DW_OP_breg15    0x7f
#define DW_OP_breg16    0x80
#define DW_OP_breg17    0x81
#define DW_OP_breg18    0x82
#define DW_OP_breg19    0x83
#define DW_OP_breg20    0x84
#define DW_OP_breg21    0x85
#define DW_OP_breg22    0x86
#define DW_OP_breg23    0x87
#define DW_OP_breg24    0x88
#define DW_OP_breg25    0x89
#define DW_OP_breg26    0x8a
#define DW_OP_breg27    0x8b
#define DW_OP_breg28    0x8c
#define DW_OP_breg29    0x8d
#define DW_OP_breg30    0x8e
#define DW_OP_breg31    0x8f
#define DW_OP_regx  0x90
#define DW_OP_fbreg 0x91
#define DW_OP_bregx 0x92
#define DW_OP_piece 0x93
#define DW_OP_deref_size    0x94
#define DW_OP_xderef_size   0x95
#define DW_OP_nop   0x96
#define DW_OP_push_object_address   0x97
#define DW_OP_call2 0x98
#define DW_OP_call4 0x99
#define DW_OP_call_ref  0x9a
#define DW_OP_form_tls_address  0x9b
#define DW_OP_call_frame_cfa    0x9c
#define DW_OP_bit_piece 0x9d
#define DW_OP_lo_user   0xe0
#define DW_OP_hi_user   0xff

/*
 * Addresses used in FDE entries in the .eh_frame section may be encoded
 * using one of the following encodings.
 */
#define DW_EH_PE_absptr 0x00
#define DW_EH_PE_omit   0xff
#define DW_EH_PE_uleb128    0x01
#define DW_EH_PE_udata2 0x02
#define DW_EH_PE_udata4 0x03
#define DW_EH_PE_udata8 0x04
#define DW_EH_PE_sleb128    0x09
#define DW_EH_PE_sdata2 0x0a
#define DW_EH_PE_sdata4 0x0b
#define DW_EH_PE_sdata8 0x0c
#define DW_EH_PE_signed 0x09

#define DW_EH_PE_pcrel  0x10

/*
 * The architecture-specific register number that contains the return
 * address in the .debug_frame table.
 */
#define DWARF_ARCH_RA_REG   17

#ifndef __ASSEMBLY__

#include <linux/compiler.h>
#include <linux/bug.h>
#include <linux/list.h>
#include <linux/module.h>

/*
 * Read either the frame pointer (r14) or the stack pointer (r15).
 * NOTE: this MUST be inlined.
 */
static __always_inline unsigned long dwarf_read_arch_reg(unsigned int reg)
{
    unsigned long value = 0;

    switch (reg) {
    case 14:
        __asm__ __volatile__("mov r14, %0\n" : "=r" (value));
        break;
    case 15:
        __asm__ __volatile__("mov r15, %0\n" : "=r" (value));
        break;
    default:
        BUG();
    }

    return value;
}

struct dwarf_cie {
    unsigned long length;
    unsigned long cie_id;
    unsigned char version;
    const char *augmentation;
    unsigned int code_alignment_factor;
    int data_alignment_factor;

    /* Which column in the rule table represents return addr of func. */
    unsigned int return_address_reg;

    unsigned char *initial_instructions;
    unsigned char *instructions_end;

    unsigned char encoding;

    unsigned long cie_pointer;

    unsigned long flags;
#define DWARF_CIE_Z_AUGMENTATION    (1 << 0)

    /* linked-list entry if this CIE is from a module */
    struct list_head link;

    struct rb_node node;
};

struct dwarf_fde {
    unsigned long length;
    unsigned long cie_pointer;
    struct dwarf_cie *cie;
    unsigned long initial_location;
    unsigned long address_range;
    unsigned char *instructions;
    unsigned char *end;

    /* linked-list entry if this FDE is from a module */
    struct list_head link;

    struct rb_node node;
};

struct dwarf_frame {
    struct dwarf_frame *prev, *next;

    unsigned long pc;

    struct list_head reg_list;

    unsigned long cfa;

    /* Valid when DW_FRAME_CFA_REG_OFFSET is set in flags */
    unsigned int cfa_register;
    unsigned int cfa_offset;

    /* Valid when DW_FRAME_CFA_REG_EXP is set in flags */
    unsigned char *cfa_expr;
    unsigned int cfa_expr_len;

    unsigned long flags;
#define DWARF_FRAME_CFA_REG_OFFSET  (1 << 0)
#define DWARF_FRAME_CFA_REG_EXP     (1 << 1)

    unsigned long return_addr;
};

struct dwarf_reg {
    struct list_head link;

    unsigned int number;

    unsigned long addr;
    unsigned long flags;
#define DWARF_REG_OFFSET    (1 << 0)
#define DWARF_VAL_OFFSET    (1 << 1)
#define DWARF_UNDEFINED     (1 << 2)
};

/*
 * Call Frame instruction opcodes.
 */
#define DW_CFA_advance_loc  0x40
#define DW_CFA_offset       0x80
#define DW_CFA_restore      0xc0
#define DW_CFA_nop      0x00
#define DW_CFA_set_loc      0x01
#define DW_CFA_advance_loc1 0x02
#define DW_CFA_advance_loc2 0x03
#define DW_CFA_advance_loc4 0x04
#define DW_CFA_offset_extended  0x05
#define DW_CFA_restore_extended 0x06
#define DW_CFA_undefined    0x07
#define DW_CFA_same_value   0x08
#define DW_CFA_register     0x09
#define DW_CFA_remember_state   0x0a
#define DW_CFA_restore_state    0x0b
#define DW_CFA_def_cfa      0x0c
#define DW_CFA_def_cfa_register 0x0d
#define DW_CFA_def_cfa_offset   0x0e
#define DW_CFA_def_cfa_expression   0x0f
#define DW_CFA_expression   0x10
#define DW_CFA_offset_extended_sf   0x11
#define DW_CFA_def_cfa_sf   0x12
#define DW_CFA_def_cfa_offset_sf    0x13
#define DW_CFA_val_offset   0x14
#define DW_CFA_val_offset_sf    0x15
#define DW_CFA_val_expression   0x16
#define DW_CFA_lo_user      0x1c
#define DW_CFA_hi_user      0x3f

/* GNU extension opcodes  */
#define DW_CFA_GNU_args_size    0x2e
#define DW_CFA_GNU_negative_offset_extended 0x2f

/*
 * Some call frame instructions encode their operands in the opcode. We
 * need some helper functions to extract both the opcode and operands
 * from an instruction.
 */
static inline unsigned int DW_CFA_opcode(unsigned long insn)
{
    return (insn & 0xc0);
}

static inline unsigned int DW_CFA_operand(unsigned long insn)
{
    return (insn & 0x3f);
}

#define DW_EH_FRAME_CIE 0       /* .eh_frame CIE IDs are 0 */
#define DW_CIE_ID   0xffffffff
#define DW64_CIE_ID 0xffffffffffffffffULL

/*
 * DWARF FDE/CIE length field values.
 */
#define DW_EXT_LO   0xfffffff0
#define DW_EXT_HI   0xffffffff
#define DW_EXT_DWARF64  DW_EXT_HI

extern struct dwarf_frame *dwarf_unwind_stack(unsigned long,
                          struct dwarf_frame *);
extern void dwarf_free_frame(struct dwarf_frame *);

extern int module_dwarf_finalize(const Elf_Ehdr *, const Elf_Shdr *,
                 struct module *);
extern void module_dwarf_cleanup(struct module *);

#endif /* !__ASSEMBLY__ */

#define CFI_STARTPROC   .cfi_startproc
#define CFI_ENDPROC .cfi_endproc
#define CFI_DEF_CFA .cfi_def_cfa
#define CFI_REGISTER    .cfi_register
#define CFI_REL_OFFSET  .cfi_rel_offset
#define CFI_UNDEFINED   .cfi_undefined

#else

/*
 * Use the asm comment character to ignore the rest of the line.
 */
#define CFI_IGNORE  !

#define CFI_STARTPROC   CFI_IGNORE
#define CFI_ENDPROC CFI_IGNORE
#define CFI_DEF_CFA CFI_IGNORE
#define CFI_REGISTER    CFI_IGNORE
#define CFI_REL_OFFSET  CFI_IGNORE
#define CFI_UNDEFINED   CFI_IGNORE

#ifndef __ASSEMBLY__
static inline void dwarf_unwinder_init(void)
{
}

#define module_dwarf_finalize(hdr, sechdrs, me) (0)
#define module_dwarf_cleanup(mod)       do { } while (0)

#endif

#endif /* CONFIG_DWARF_UNWINDER */

#endif /* __ASM_SH_DWARF_H */