gas: fix a few omissions in .cfi_label handling

[external/binutils.git] / gas / dw2gencfi.c

/* dw2gencfi.c - Support for generating Dwarf2 CFI information.
   Copyright (C) 2003-2015 Free Software Foundation, Inc.
   Contributed by Michal Ludvig <mludvig@suse.cz>

   This file is part of GAS, the GNU Assembler.

   GAS is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3, or (at your option)
   any later version.

   GAS is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with GAS; see the file COPYING.  If not, write to the Free
   Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
   02110-1301, USA.  */

#include "as.h"
#include "dw2gencfi.h"
#include "subsegs.h"
#include "dwarf2dbg.h"

#ifdef TARGET_USE_CFIPOP

/* By default, use difference expressions if DIFF_EXPR_OK is defined.  */
#ifndef CFI_DIFF_EXPR_OK
# ifdef DIFF_EXPR_OK
#  define CFI_DIFF_EXPR_OK 1
# else
#  define CFI_DIFF_EXPR_OK 0
# endif
#endif

#ifndef CFI_DIFF_LSDA_OK
#define CFI_DIFF_LSDA_OK CFI_DIFF_EXPR_OK
#endif

#if CFI_DIFF_EXPR_OK == 1 && CFI_DIFF_LSDA_OK == 0
# error "CFI_DIFF_EXPR_OK should imply CFI_DIFF_LSDA_OK"
#endif

/* We re-use DWARF2_LINE_MIN_INSN_LENGTH for the code alignment field
   of the CIE.  Default to 1 if not otherwise specified.  */
#ifndef DWARF2_LINE_MIN_INSN_LENGTH
#define DWARF2_LINE_MIN_INSN_LENGTH 1
#endif

/* By default, use 32-bit relocations from .eh_frame into .text.  */
#ifndef DWARF2_FDE_RELOC_SIZE
#define DWARF2_FDE_RELOC_SIZE 4
#endif

/* By default, use a read-only .eh_frame section.  */
#ifndef DWARF2_EH_FRAME_READ_ONLY
#define DWARF2_EH_FRAME_READ_ONLY SEC_READONLY
#endif

#ifndef EH_FRAME_ALIGNMENT
#define EH_FRAME_ALIGNMENT (bfd_get_arch_size (stdoutput) == 64 ? 3 : 2)
#endif

#ifndef tc_cfi_frame_initial_instructions
#define tc_cfi_frame_initial_instructions() ((void)0)
#endif

#ifndef tc_cfi_startproc
# define tc_cfi_startproc() ((void)0)
#endif

#ifndef tc_cfi_endproc
# define tc_cfi_endproc(fde) ((void) (fde))
#endif

#ifndef DWARF2_FORMAT
#define DWARF2_FORMAT(SEC) dwarf2_format_32bit
#endif

#ifndef DWARF2_ADDR_SIZE
#define DWARF2_ADDR_SIZE(bfd) (bfd_arch_bits_per_address (bfd) / 8)
#endif

#if SUPPORT_FRAME_LINKONCE
#define CUR_SEG(structp) structp->cur_seg
#define SET_CUR_SEG(structp, seg) structp->cur_seg = seg
#define HANDLED(structp) structp->handled
#define SET_HANDLED(structp, val) structp->handled = val
#else
#define CUR_SEG(structp) NULL
#define SET_CUR_SEG(structp, seg) (void) (0 && seg)
#define HANDLED(structp) 0
#define SET_HANDLED(structp, val) (void) (0 && val)
#endif

/* Private segment collection list.  */
struct dwcfi_seg_list
{
  segT   seg;
  int    subseg;
  char * seg_name;
};

#define FRAME_NAME ".eh_frame"

static struct hash_control *dwcfi_hash;

/* Build based on segment the derived .debug_...
   segment name containing origin segment's postfix name part.  */

static char *
get_debugseg_name (segT seg, const char *base_name)
{
  const char *name;

  if (!seg)
    name = "";
  else
    {
      const char * dollar;
      const char * dot;

      name = bfd_get_section_name (stdoutput, seg);

      dollar = strchr (name, '$');
      dot = strchr (name + 1, '.');

      if (!dollar && !dot)
        name = "";
      else if (!dollar)
        name = dot;
      else if (!dot)
        name = dollar;
      else if (dot < dollar)
        name = dot;
      else
        name = dollar;
    }

  return concat (base_name, name, NULL);
}

/* Allocate a dwcfi_seg_list structure.  */

static struct dwcfi_seg_list *
alloc_debugseg_item (segT seg, int subseg, char *name)
{
  struct dwcfi_seg_list *r;

  r = (struct dwcfi_seg_list *)
    xmalloc (sizeof (struct dwcfi_seg_list) + strlen (name));
  r->seg = seg;
  r->subseg = subseg;
  r->seg_name = name;
  return r;
}

static segT
is_now_linkonce_segment (void)
{
  if ((bfd_get_section_flags (stdoutput, now_seg)
       & (SEC_LINK_ONCE | SEC_LINK_DUPLICATES_DISCARD
          | SEC_LINK_DUPLICATES_ONE_ONLY | SEC_LINK_DUPLICATES_SAME_SIZE
          | SEC_LINK_DUPLICATES_SAME_CONTENTS)) != 0)
    return now_seg;
  return NULL;
}

/* Generate debug... segment with same linkonce properties
   of based segment.  */

static segT
make_debug_seg (segT cseg, char *name, int sflags)
{
  segT save_seg = now_seg;
  int save_subseg = now_subseg;
  segT r;
  flagword flags;

  r = subseg_new (name, 0);

  /* Check if code segment is marked as linked once.  */
  if (!cseg)
    flags = 0;
  else
    flags = bfd_get_section_flags (stdoutput, cseg)
      & (SEC_LINK_ONCE | SEC_LINK_DUPLICATES_DISCARD
         | SEC_LINK_DUPLICATES_ONE_ONLY | SEC_LINK_DUPLICATES_SAME_SIZE
         | SEC_LINK_DUPLICATES_SAME_CONTENTS);

  /* Add standard section flags.  */
  flags |= sflags;

  /* Apply possibly linked once flags to new generated segment, too.  */
  if (!bfd_set_section_flags (stdoutput, r, flags))
    as_bad (_("bfd_set_section_flags: %s"),
            bfd_errmsg (bfd_get_error ()));

  /* Restore to previous segment.  */
  if (save_seg != NULL)
    subseg_set (save_seg, save_subseg);
  return r;
}

static void
dwcfi_hash_insert (const char *name, struct dwcfi_seg_list *item)
{
  const char *error_string;

  if ((error_string = hash_jam (dwcfi_hash, name, (char *) item)))
    as_fatal (_("Inserting \"%s\" into structure table failed: %s"),
              name, error_string);
}

static struct dwcfi_seg_list *
dwcfi_hash_find (char *name)
{
  return (struct dwcfi_seg_list *) hash_find (dwcfi_hash, name);
}

static struct dwcfi_seg_list *
dwcfi_hash_find_or_make (segT cseg, const char *base_name, int flags)
{
  struct dwcfi_seg_list *item;
  char *name;

  /* Initialize dwcfi_hash once.  */
  if (!dwcfi_hash)
    dwcfi_hash = hash_new ();

  name = get_debugseg_name (cseg, base_name);

  item = dwcfi_hash_find (name);
  if (!item)
    {
      item = alloc_debugseg_item (make_debug_seg (cseg, name, flags), 0, name);

      dwcfi_hash_insert (item->seg_name, item);
    }
  else
    free (name);

  return item;
}

/* ??? Share this with dwarf2cfg.c.  */
#ifndef TC_DWARF2_EMIT_OFFSET
#define TC_DWARF2_EMIT_OFFSET  generic_dwarf2_emit_offset

/* Create an offset to .dwarf2_*.  */

static void
generic_dwarf2_emit_offset (symbolS *symbol, unsigned int size)
{
  expressionS exp;

  exp.X_op = O_symbol;
  exp.X_add_symbol = symbol;
  exp.X_add_number = 0;
  emit_expr (&exp, size);
}
#endif

struct cfi_escape_data
{
  struct cfi_escape_data *next;
  expressionS exp;
};

struct cie_entry
{
  struct cie_entry *next;
#if SUPPORT_FRAME_LINKONCE
  segT cur_seg;
#endif
  symbolS *start_address;
  unsigned int return_column;
  unsigned int signal_frame;
  unsigned char per_encoding;
  unsigned char lsda_encoding;
  expressionS personality;
  struct cfi_insn_data *first, *last;
};

/* List of FDE entries.  */

struct fde_entry *all_fde_data;
static struct fde_entry **last_fde_data = &all_fde_data;

/* List of CIEs so that they could be reused.  */
static struct cie_entry *cie_root;

/* Stack of old CFI data, for save/restore.  */
struct cfa_save_data
{
  struct cfa_save_data *next;
  offsetT cfa_offset;
};

/* Current open FDE entry.  */
struct frch_cfi_data
{
  struct fde_entry *cur_fde_data;
  symbolS *last_address;
  offsetT cur_cfa_offset;
  struct cfa_save_data *cfa_save_stack;
};
\f
/* Construct a new FDE structure and add it to the end of the fde list.  */

static struct fde_entry *
alloc_fde_entry (void)
{
  struct fde_entry *fde = (struct fde_entry *)
      xcalloc (1, sizeof (struct fde_entry));

  frchain_now->frch_cfi_data = (struct frch_cfi_data *)
      xcalloc (1, sizeof (struct frch_cfi_data));
  frchain_now->frch_cfi_data->cur_fde_data = fde;
  *last_fde_data = fde;
  last_fde_data = &fde->next;
  SET_CUR_SEG (fde, is_now_linkonce_segment ());
  SET_HANDLED (fde, 0);
  fde->last = &fde->data;
  fde->return_column = DWARF2_DEFAULT_RETURN_COLUMN;
  fde->per_encoding = DW_EH_PE_omit;
  fde->lsda_encoding = DW_EH_PE_omit;

  return fde;
}

/* The following functions are available for a backend to construct its
   own unwind information, usually from legacy unwind directives.  */

/* Construct a new INSN structure and add it to the end of the insn list
   for the currently active FDE.  */

static struct cfi_insn_data *
alloc_cfi_insn_data (void)
{
  struct cfi_insn_data *insn = (struct cfi_insn_data *)
      xcalloc (1, sizeof (struct cfi_insn_data));
  struct fde_entry *cur_fde_data = frchain_now->frch_cfi_data->cur_fde_data;

  *cur_fde_data->last = insn;
  cur_fde_data->last = &insn->next;
  SET_CUR_SEG (insn, is_now_linkonce_segment ());
  return insn;
}

/* Construct a new FDE structure that begins at LABEL.  */

void
cfi_new_fde (symbolS *label)
{
  struct fde_entry *fde = alloc_fde_entry ();
  fde->start_address = label;
  frchain_now->frch_cfi_data->last_address = label;
}

/* End the currently open FDE.  */

void
cfi_end_fde (symbolS *label)
{
  frchain_now->frch_cfi_data->cur_fde_data->end_address = label;
  free (frchain_now->frch_cfi_data);
  frchain_now->frch_cfi_data = NULL;
}

/* Set the return column for the current FDE.  */

void
cfi_set_return_column (unsigned regno)
{
  frchain_now->frch_cfi_data->cur_fde_data->return_column = regno;
}

/* Universal functions to store new instructions.  */

static void
cfi_add_CFA_insn (int insn)
{
  struct cfi_insn_data *insn_ptr = alloc_cfi_insn_data ();

  insn_ptr->insn = insn;
}

static void
cfi_add_CFA_insn_reg (int insn, unsigned regno)
{
  struct cfi_insn_data *insn_ptr = alloc_cfi_insn_data ();

  insn_ptr->insn = insn;
  insn_ptr->u.r = regno;
}

static void
cfi_add_CFA_insn_offset (int insn, offsetT offset)
{
  struct cfi_insn_data *insn_ptr = alloc_cfi_insn_data ();

  insn_ptr->insn = insn;
  insn_ptr->u.i = offset;
}

static void
cfi_add_CFA_insn_reg_reg (int insn, unsigned reg1, unsigned reg2)
{
  struct cfi_insn_data *insn_ptr = alloc_cfi_insn_data ();

  insn_ptr->insn = insn;
  insn_ptr->u.rr.reg1 = reg1;
  insn_ptr->u.rr.reg2 = reg2;
}

static void
cfi_add_CFA_insn_reg_offset (int insn, unsigned regno, offsetT offset)
{
  struct cfi_insn_data *insn_ptr = alloc_cfi_insn_data ();

  insn_ptr->insn = insn;
  insn_ptr->u.ri.reg = regno;
  insn_ptr->u.ri.offset = offset;
}

/* Add a CFI insn to advance the PC from the last address to LABEL.  */

void
cfi_add_advance_loc (symbolS *label)
{
  struct cfi_insn_data *insn = alloc_cfi_insn_data ();

  insn->insn = DW_CFA_advance_loc;
  insn->u.ll.lab1 = frchain_now->frch_cfi_data->last_address;
  insn->u.ll.lab2 = label;

  frchain_now->frch_cfi_data->last_address = label;
}

/* Add a CFI insn to label the current position in the CFI segment.  */

void
cfi_add_label (const char *name)
{
  unsigned int len = strlen (name) + 1;
  struct cfi_insn_data *insn = alloc_cfi_insn_data ();

  insn->insn = CFI_label;
  obstack_grow (&notes, name, len);
  insn->u.sym_name = (char *) obstack_finish (&notes);
}

/* Add a DW_CFA_offset record to the CFI data.  */

void
cfi_add_CFA_offset (unsigned regno, offsetT offset)
{
  unsigned int abs_data_align;

  gas_assert (DWARF2_CIE_DATA_ALIGNMENT != 0);
  cfi_add_CFA_insn_reg_offset (DW_CFA_offset, regno, offset);

  abs_data_align = (DWARF2_CIE_DATA_ALIGNMENT < 0
                    ? -DWARF2_CIE_DATA_ALIGNMENT : DWARF2_CIE_DATA_ALIGNMENT);
  if (offset % abs_data_align)
    as_bad (_("register save offset not a multiple of %u"), abs_data_align);
}

/* Add a DW_CFA_def_cfa record to the CFI data.  */

void
cfi_add_CFA_def_cfa (unsigned regno, offsetT offset)
{
  cfi_add_CFA_insn_reg_offset (DW_CFA_def_cfa, regno, offset);
  frchain_now->frch_cfi_data->cur_cfa_offset = offset;
}

/* Add a DW_CFA_register record to the CFI data.  */

void
cfi_add_CFA_register (unsigned reg1, unsigned reg2)
{
  cfi_add_CFA_insn_reg_reg (DW_CFA_register, reg1, reg2);
}

/* Add a DW_CFA_def_cfa_register record to the CFI data.  */

void
cfi_add_CFA_def_cfa_register (unsigned regno)
{
  cfi_add_CFA_insn_reg (DW_CFA_def_cfa_register, regno);
}

/* Add a DW_CFA_def_cfa_offset record to the CFI data.  */

void
cfi_add_CFA_def_cfa_offset (offsetT offset)
{
  cfi_add_CFA_insn_offset (DW_CFA_def_cfa_offset, offset);
  frchain_now->frch_cfi_data->cur_cfa_offset = offset;
}

void
cfi_add_CFA_restore (unsigned regno)
{
  cfi_add_CFA_insn_reg (DW_CFA_restore, regno);
}

void
cfi_add_CFA_undefined (unsigned regno)
{
  cfi_add_CFA_insn_reg (DW_CFA_undefined, regno);
}

void
cfi_add_CFA_same_value (unsigned regno)
{
  cfi_add_CFA_insn_reg (DW_CFA_same_value, regno);
}

void
cfi_add_CFA_remember_state (void)
{
  struct cfa_save_data *p;

  cfi_add_CFA_insn (DW_CFA_remember_state);

  p = (struct cfa_save_data *) xmalloc (sizeof (*p));
  p->cfa_offset = frchain_now->frch_cfi_data->cur_cfa_offset;
  p->next = frchain_now->frch_cfi_data->cfa_save_stack;
  frchain_now->frch_cfi_data->cfa_save_stack = p;
}

void
cfi_add_CFA_restore_state (void)
{
  struct cfa_save_data *p;

  cfi_add_CFA_insn (DW_CFA_restore_state);

  p = frchain_now->frch_cfi_data->cfa_save_stack;
  if (p)
    {
      frchain_now->frch_cfi_data->cur_cfa_offset = p->cfa_offset;
      frchain_now->frch_cfi_data->cfa_save_stack = p->next;
      free (p);
    }
  else
    as_bad (_("CFI state restore without previous remember"));
}

\f
/* Parse CFI assembler directives.  */

static void dot_cfi (int);
static void dot_cfi_escape (int);
static void dot_cfi_sections (int);
static void dot_cfi_startproc (int);
static void dot_cfi_endproc (int);
static void dot_cfi_personality (int);
static void dot_cfi_lsda (int);
static void dot_cfi_val_encoded_addr (int);
static void dot_cfi_label (int);

const pseudo_typeS cfi_pseudo_table[] =
  {
    { "cfi_sections", dot_cfi_sections, 0 },
    { "cfi_startproc", dot_cfi_startproc, 0 },
    { "cfi_endproc", dot_cfi_endproc, 0 },
    { "cfi_def_cfa", dot_cfi, DW_CFA_def_cfa },
    { "cfi_def_cfa_register", dot_cfi, DW_CFA_def_cfa_register },
    { "cfi_def_cfa_offset", dot_cfi, DW_CFA_def_cfa_offset },
    { "cfi_adjust_cfa_offset", dot_cfi, CFI_adjust_cfa_offset },
    { "cfi_offset", dot_cfi, DW_CFA_offset },
    { "cfi_rel_offset", dot_cfi, CFI_rel_offset },
    { "cfi_register", dot_cfi, DW_CFA_register },
    { "cfi_return_column", dot_cfi, CFI_return_column },
    { "cfi_restore", dot_cfi, DW_CFA_restore },
    { "cfi_undefined", dot_cfi, DW_CFA_undefined },
    { "cfi_same_value", dot_cfi, DW_CFA_same_value },
    { "cfi_remember_state", dot_cfi, DW_CFA_remember_state },
    { "cfi_restore_state", dot_cfi, DW_CFA_restore_state },
    { "cfi_window_save", dot_cfi, DW_CFA_GNU_window_save },
    { "cfi_escape", dot_cfi_escape, 0 },
    { "cfi_signal_frame", dot_cfi, CFI_signal_frame },
    { "cfi_personality", dot_cfi_personality, 0 },
    { "cfi_lsda", dot_cfi_lsda, 0 },
    { "cfi_val_encoded_addr", dot_cfi_val_encoded_addr, 0 },
    { "cfi_label", dot_cfi_label, 0 },
    { NULL, NULL, 0 }
  };

static void
cfi_parse_separator (void)
{
  SKIP_WHITESPACE ();
  if (*input_line_pointer == ',')
    input_line_pointer++;
  else
    as_bad (_("missing separator"));
}

#ifndef tc_parse_to_dw2regnum
static void
tc_parse_to_dw2regnum (expressionS *exp)
{
# ifdef tc_regname_to_dw2regnum
  SKIP_WHITESPACE ();
  if (is_name_beginner (*input_line_pointer)
      || (*input_line_pointer == '%'
          && is_name_beginner (*++input_line_pointer)))
    {
      char *name, c;

      name = input_line_pointer;
      c = get_symbol_end ();

      exp->X_op = O_constant;
      exp->X_add_number = tc_regname_to_dw2regnum (name);

      *input_line_pointer = c;
    }
  else
# endif
    expression_and_evaluate (exp);
}
#endif

static unsigned
cfi_parse_reg (void)
{
  int regno;
  expressionS exp;

  tc_parse_to_dw2regnum (&exp);
  switch (exp.X_op)
    {
    case O_register:
    case O_constant:
      regno = exp.X_add_number;
      break;

    default:
      regno = -1;
      break;
    }

  if (regno < 0)
    {
      as_bad (_("bad register expression"));
      regno = 0;
    }

  return regno;
}

static offsetT
cfi_parse_const (void)
{
  return get_absolute_expression ();
}

static void
dot_cfi (int arg)
{
  offsetT offset;
  unsigned reg1, reg2;

  if (frchain_now->frch_cfi_data == NULL)
    {
      as_bad (_("CFI instruction used without previous .cfi_startproc"));
      ignore_rest_of_line ();
      return;
    }

  /* If the last address was not at the current PC, advance to current.  */
  if (symbol_get_frag (frchain_now->frch_cfi_data->last_address) != frag_now
      || S_GET_VALUE (frchain_now->frch_cfi_data->last_address)
         != frag_now_fix ())
    cfi_add_advance_loc (symbol_temp_new_now ());

  switch (arg)
    {
    case DW_CFA_offset:
      reg1 = cfi_parse_reg ();
      cfi_parse_separator ();
      offset = cfi_parse_const ();
      cfi_add_CFA_offset (reg1, offset);
      break;

    case CFI_rel_offset:
      reg1 = cfi_parse_reg ();
      cfi_parse_separator ();
      offset = cfi_parse_const ();
      cfi_add_CFA_offset (reg1,
                          offset - frchain_now->frch_cfi_data->cur_cfa_offset);
      break;

    case DW_CFA_def_cfa:
      reg1 = cfi_parse_reg ();
      cfi_parse_separator ();
      offset = cfi_parse_const ();
      cfi_add_CFA_def_cfa (reg1, offset);
      break;

    case DW_CFA_register:
      reg1 = cfi_parse_reg ();
      cfi_parse_separator ();
      reg2 = cfi_parse_reg ();
      cfi_add_CFA_register (reg1, reg2);
      break;

    case DW_CFA_def_cfa_register:
      reg1 = cfi_parse_reg ();
      cfi_add_CFA_def_cfa_register (reg1);
      break;

    case DW_CFA_def_cfa_offset:
      offset = cfi_parse_const ();
      cfi_add_CFA_def_cfa_offset (offset);
      break;

    case CFI_adjust_cfa_offset:
      offset = cfi_parse_const ();
      cfi_add_CFA_def_cfa_offset (frchain_now->frch_cfi_data->cur_cfa_offset
                                  + offset);
      break;

    case DW_CFA_restore:
      for (;;)
        {
          reg1 = cfi_parse_reg ();
          cfi_add_CFA_restore (reg1);
          SKIP_WHITESPACE ();
          if (*input_line_pointer != ',')
            break;
          ++input_line_pointer;
        }
      break;

    case DW_CFA_undefined:
      for (;;)
        {
          reg1 = cfi_parse_reg ();
          cfi_add_CFA_undefined (reg1);
          SKIP_WHITESPACE ();
          if (*input_line_pointer != ',')
            break;
          ++input_line_pointer;
        }
      break;

    case DW_CFA_same_value:
      reg1 = cfi_parse_reg ();
      cfi_add_CFA_same_value (reg1);
      break;

    case CFI_return_column:
      reg1 = cfi_parse_reg ();
      cfi_set_return_column (reg1);
      break;

    case DW_CFA_remember_state:
      cfi_add_CFA_remember_state ();
      break;

    case DW_CFA_restore_state:
      cfi_add_CFA_restore_state ();
      break;

    case DW_CFA_GNU_window_save:
      cfi_add_CFA_insn (DW_CFA_GNU_window_save);
      break;

    case CFI_signal_frame:
      frchain_now->frch_cfi_data->cur_fde_data->signal_frame = 1;
      break;

    default:
      abort ();
    }

  demand_empty_rest_of_line ();
}

static void
dot_cfi_escape (int ignored ATTRIBUTE_UNUSED)
{
  struct cfi_escape_data *head, **tail, *e;
  struct cfi_insn_data *insn;

  if (frchain_now->frch_cfi_data == NULL)
    {
      as_bad (_("CFI instruction used without previous .cfi_startproc"));
      ignore_rest_of_line ();
      return;
    }

  /* If the last address was not at the current PC, advance to current.  */
  if (symbol_get_frag (frchain_now->frch_cfi_data->last_address) != frag_now
      || S_GET_VALUE (frchain_now->frch_cfi_data->last_address)
         != frag_now_fix ())
    cfi_add_advance_loc (symbol_temp_new_now ());

  tail = &head;
  do
    {
      e = (struct cfi_escape_data *) xmalloc (sizeof (*e));
      do_parse_cons_expression (&e->exp, 1);
      *tail = e;
      tail = &e->next;
    }
  while (*input_line_pointer++ == ',');
  *tail = NULL;

  insn = alloc_cfi_insn_data ();
  insn->insn = CFI_escape;
  insn->u.esc = head;

  --input_line_pointer;
  demand_empty_rest_of_line ();
}

static void
dot_cfi_personality (int ignored ATTRIBUTE_UNUSED)
{
  struct fde_entry *fde;
  offsetT encoding;

  if (frchain_now->frch_cfi_data == NULL)
    {
      as_bad (_("CFI instruction used without previous .cfi_startproc"));
      ignore_rest_of_line ();
      return;
    }

  fde = frchain_now->frch_cfi_data->cur_fde_data;
  encoding = cfi_parse_const ();
  if (encoding == DW_EH_PE_omit)
    {
      demand_empty_rest_of_line ();
      fde->per_encoding = encoding;
      return;
    }

  if ((encoding & 0xff) != encoding
      || ((encoding & 0x70) != 0
#if CFI_DIFF_EXPR_OK || defined tc_cfi_emit_pcrel_expr
          && (encoding & 0x70) != DW_EH_PE_pcrel
#endif
          )
         /* leb128 can be handled, but does something actually need it?  */
      || (encoding & 7) == DW_EH_PE_uleb128
      || (encoding & 7) > DW_EH_PE_udata8)
    {
      as_bad (_("invalid or unsupported encoding in .cfi_personality"));
      ignore_rest_of_line ();
      return;
    }

  if (*input_line_pointer++ != ',')
    {
      as_bad (_(".cfi_personality requires encoding and symbol arguments"));
      ignore_rest_of_line ();
      return;
    }

  expression_and_evaluate (&fde->personality);
  switch (fde->personality.X_op)
    {
    case O_symbol:
      break;
    case O_constant:
      if ((encoding & 0x70) == DW_EH_PE_pcrel)
        encoding = DW_EH_PE_omit;
      break;
    default:
      encoding = DW_EH_PE_omit;
      break;
    }

  fde->per_encoding = encoding;

  if (encoding == DW_EH_PE_omit)
    {
      as_bad (_("wrong second argument to .cfi_personality"));
      ignore_rest_of_line ();
      return;
    }

  demand_empty_rest_of_line ();
}

static void
dot_cfi_lsda (int ignored ATTRIBUTE_UNUSED)
{
  struct fde_entry *fde;
  offsetT encoding;

  if (frchain_now->frch_cfi_data == NULL)
    {
      as_bad (_("CFI instruction used without previous .cfi_startproc"));
      ignore_rest_of_line ();
      return;
    }

  fde = frchain_now->frch_cfi_data->cur_fde_data;
  encoding = cfi_parse_const ();
  if (encoding == DW_EH_PE_omit)
    {
      demand_empty_rest_of_line ();
      fde->lsda_encoding = encoding;
      return;
    }

  if ((encoding & 0xff) != encoding
      || ((encoding & 0x70) != 0
#if CFI_DIFF_LSDA_OK || defined tc_cfi_emit_pcrel_expr
          && (encoding & 0x70) != DW_EH_PE_pcrel
#endif
          )
         /* leb128 can be handled, but does something actually need it?  */
      || (encoding & 7) == DW_EH_PE_uleb128
      || (encoding & 7) > DW_EH_PE_udata8)
    {
      as_bad (_("invalid or unsupported encoding in .cfi_lsda"));
      ignore_rest_of_line ();
      return;
    }

  if (*input_line_pointer++ != ',')
    {
      as_bad (_(".cfi_lsda requires encoding and symbol arguments"));
      ignore_rest_of_line ();
      return;
    }

  fde->lsda_encoding = encoding;

  expression_and_evaluate (&fde->lsda);
  switch (fde->lsda.X_op)
    {
    case O_symbol:
      break;
    case O_constant:
      if ((encoding & 0x70) == DW_EH_PE_pcrel)
        encoding = DW_EH_PE_omit;
      break;
    default:
      encoding = DW_EH_PE_omit;
      break;
    }

  fde->lsda_encoding = encoding;

  if (encoding == DW_EH_PE_omit)
    {
      as_bad (_("wrong second argument to .cfi_lsda"));
      ignore_rest_of_line ();
      return;
    }

  demand_empty_rest_of_line ();
}

static void
dot_cfi_val_encoded_addr (int ignored ATTRIBUTE_UNUSED)
{
  struct cfi_insn_data *insn_ptr;
  offsetT encoding;

  if (frchain_now->frch_cfi_data == NULL)
    {
      as_bad (_("CFI instruction used without previous .cfi_startproc"));
      ignore_rest_of_line ();
      return;
    }

  /* If the last address was not at the current PC, advance to current.  */
  if (symbol_get_frag (frchain_now->frch_cfi_data->last_address) != frag_now
      || S_GET_VALUE (frchain_now->frch_cfi_data->last_address)
         != frag_now_fix ())
    cfi_add_advance_loc (symbol_temp_new_now ());

  insn_ptr = alloc_cfi_insn_data ();
  insn_ptr->insn = CFI_val_encoded_addr;

  insn_ptr->u.ea.reg = cfi_parse_reg ();

  cfi_parse_separator ();
  encoding = cfi_parse_const ();
  if ((encoding & 0xff) != encoding
      || ((encoding & 0x70) != 0
#if CFI_DIFF_EXPR_OK || defined tc_cfi_emit_pcrel_expr
          && (encoding & 0x70) != DW_EH_PE_pcrel
#endif
          )
         /* leb128 can be handled, but does something actually need it?  */
      || (encoding & 7) == DW_EH_PE_uleb128
      || (encoding & 7) > DW_EH_PE_udata8)
    {
      as_bad (_("invalid or unsupported encoding in .cfi_lsda"));
      encoding = DW_EH_PE_omit;
    }

  cfi_parse_separator ();
  expression_and_evaluate (&insn_ptr->u.ea.exp);
  switch (insn_ptr->u.ea.exp.X_op)
    {
    case O_symbol:
      break;
    case O_constant:
      if ((encoding & 0x70) != DW_EH_PE_pcrel)
        break;
    default:
      encoding = DW_EH_PE_omit;
      break;
    }

  insn_ptr->u.ea.encoding = encoding;
  if (encoding == DW_EH_PE_omit)
    {
      as_bad (_("wrong third argument to .cfi_val_encoded_addr"));
      ignore_rest_of_line ();
      return;
    }

  demand_empty_rest_of_line ();
}

static void
dot_cfi_label (int ignored ATTRIBUTE_UNUSED)
{
  char *name = read_symbol_name ();

  if (name == NULL)
    return;

  /* If the last address was not at the current PC, advance to current.  */
  if (symbol_get_frag (frchain_now->frch_cfi_data->last_address) != frag_now
      || S_GET_VALUE (frchain_now->frch_cfi_data->last_address)
         != frag_now_fix ())
    cfi_add_advance_loc (symbol_temp_new_now ());

  cfi_add_label (name);

  demand_empty_rest_of_line ();
}

/* By default emit .eh_frame only, not .debug_frame.  */
#define CFI_EMIT_eh_frame       (1 << 0)
#define CFI_EMIT_debug_frame    (1 << 1)
#define CFI_EMIT_target         (1 << 2)
static int cfi_sections = CFI_EMIT_eh_frame;

static void
dot_cfi_sections (int ignored ATTRIBUTE_UNUSED)
{
  int sections = 0;

  SKIP_WHITESPACE ();
  if (is_name_beginner (*input_line_pointer))
    while (1)
      {
        char *name, c;

        name = input_line_pointer;
        c = get_symbol_end ();

        if (strncmp (name, ".eh_frame", sizeof ".eh_frame") == 0
            && name[9] != '_')
          sections |= CFI_EMIT_eh_frame;
        else if (strncmp (name, ".debug_frame", sizeof ".debug_frame") == 0)
          sections |= CFI_EMIT_debug_frame;
#ifdef tc_cfi_section_name
        else if (strcmp (name, tc_cfi_section_name) == 0)
          sections |= CFI_EMIT_target;
#endif
        else
          {
            *input_line_pointer = c;
            input_line_pointer = name;
            break;
          }

        *input_line_pointer = c;
        SKIP_WHITESPACE ();
        if (*input_line_pointer == ',')
          {
            name = input_line_pointer++;
            SKIP_WHITESPACE ();
            if (!is_name_beginner (*input_line_pointer))
              {
                input_line_pointer = name;
                break;
              }
          }
        else if (is_name_beginner (*input_line_pointer))
          break;
      }

  demand_empty_rest_of_line ();
  cfi_sections = sections;
}

static void
dot_cfi_startproc (int ignored ATTRIBUTE_UNUSED)
{
  int simple = 0;

  if (frchain_now->frch_cfi_data != NULL)
    {
      as_bad (_("previous CFI entry not closed (missing .cfi_endproc)"));
      ignore_rest_of_line ();
      return;
    }

  cfi_new_fde (symbol_temp_new_now ());

  SKIP_WHITESPACE ();
  if (is_name_beginner (*input_line_pointer))
    {
      char *name, c;

      name = input_line_pointer;
      c = get_symbol_end ();

      if (strcmp (name, "simple") == 0)
        {
          simple = 1;
          *input_line_pointer = c;
        }
      else
        input_line_pointer = name;
    }
  demand_empty_rest_of_line ();

  frchain_now->frch_cfi_data->cur_cfa_offset = 0;
  if (!simple)
    tc_cfi_frame_initial_instructions ();

  if ((cfi_sections & CFI_EMIT_target) != 0)
    tc_cfi_startproc ();
}

static void
dot_cfi_endproc (int ignored ATTRIBUTE_UNUSED)
{
  struct fde_entry *fde;

  if (frchain_now->frch_cfi_data == NULL)
    {
      as_bad (_(".cfi_endproc without corresponding .cfi_startproc"));
      ignore_rest_of_line ();
      return;
    }

  fde = frchain_now->frch_cfi_data->cur_fde_data;

  cfi_end_fde (symbol_temp_new_now ());

  demand_empty_rest_of_line ();

  if ((cfi_sections & CFI_EMIT_target) != 0)
    tc_cfi_endproc (fde);
}

\f
/* Emit a single byte into the current segment.  */

static inline void
out_one (int byte)
{
  FRAG_APPEND_1_CHAR (byte);
}

/* Emit a two-byte word into the current segment.  */

static inline void
out_two (int data)
{
  md_number_to_chars (frag_more (2), data, 2);
}

/* Emit a four byte word into the current segment.  */

static inline void
out_four (int data)
{
  md_number_to_chars (frag_more (4), data, 4);
}

/* Emit an unsigned "little-endian base 128" number.  */

static void
out_uleb128 (addressT value)
{
  output_leb128 (frag_more (sizeof_leb128 (value, 0)), value, 0);
}

/* Emit an unsigned "little-endian base 128" number.  */

static void
out_sleb128 (offsetT value)
{
  output_leb128 (frag_more (sizeof_leb128 (value, 1)), value, 1);
}

static void
output_cfi_insn (struct cfi_insn_data *insn)
{
  offsetT offset;
  unsigned int regno;

  switch (insn->insn)
    {
    case DW_CFA_advance_loc:
      {
        symbolS *from = insn->u.ll.lab1;
        symbolS *to = insn->u.ll.lab2;

        if (symbol_get_frag (to) == symbol_get_frag (from))
          {
            addressT delta = S_GET_VALUE (to) - S_GET_VALUE (from);
            addressT scaled = delta / DWARF2_LINE_MIN_INSN_LENGTH;

            if (scaled <= 0x3F)
              out_one (DW_CFA_advance_loc + scaled);
            else if (scaled <= 0xFF)
              {
                out_one (DW_CFA_advance_loc1);
                out_one (scaled);
              }
            else if (scaled <= 0xFFFF)
              {
                out_one (DW_CFA_advance_loc2);
                out_two (scaled);
              }
            else
              {
                out_one (DW_CFA_advance_loc4);
                out_four (scaled);
              }
          }
        else
          {
            expressionS exp;

            exp.X_op = O_subtract;
            exp.X_add_symbol = to;
            exp.X_op_symbol = from;
            exp.X_add_number = 0;

            /* The code in ehopt.c expects that one byte of the encoding
               is already allocated to the frag.  This comes from the way
               that it scans the .eh_frame section looking first for the
               .byte DW_CFA_advance_loc4.  */
            *frag_more (1) = DW_CFA_advance_loc4;

            frag_var (rs_cfa, 4, 0, DWARF2_LINE_MIN_INSN_LENGTH << 3,
                      make_expr_symbol (&exp), frag_now_fix () - 1,
                      (char *) frag_now);
          }
      }
      break;

    case DW_CFA_def_cfa:
      offset = insn->u.ri.offset;
      if (offset < 0)
        {
          out_one (DW_CFA_def_cfa_sf);
          out_uleb128 (insn->u.ri.reg);
          out_sleb128 (offset / DWARF2_CIE_DATA_ALIGNMENT);
        }
      else
        {
          out_one (DW_CFA_def_cfa);
          out_uleb128 (insn->u.ri.reg);
          out_uleb128 (offset);
        }
      break;

    case DW_CFA_def_cfa_register:
    case DW_CFA_undefined:
    case DW_CFA_same_value:
      out_one (insn->insn);
      out_uleb128 (insn->u.r);
      break;

    case DW_CFA_def_cfa_offset:
      offset = insn->u.i;
      if (offset < 0)
        {
          out_one (DW_CFA_def_cfa_offset_sf);
          out_sleb128 (offset / DWARF2_CIE_DATA_ALIGNMENT);
        }
      else
        {
          out_one (DW_CFA_def_cfa_offset);
          out_uleb128 (offset);
        }
      break;

    case DW_CFA_restore:
      regno = insn->u.r;
      if (regno <= 0x3F)
        {
          out_one (DW_CFA_restore + regno);
        }
      else
        {
          out_one (DW_CFA_restore_extended);
          out_uleb128 (regno);
        }
      break;

    case DW_CFA_offset:
      regno = insn->u.ri.reg;
      offset = insn->u.ri.offset / DWARF2_CIE_DATA_ALIGNMENT;
      if (offset < 0)
        {
          out_one (DW_CFA_offset_extended_sf);
          out_uleb128 (regno);
          out_sleb128 (offset);
        }
      else if (regno <= 0x3F)
        {
          out_one (DW_CFA_offset + regno);
          out_uleb128 (offset);
        }
      else
        {
          out_one (DW_CFA_offset_extended);
          out_uleb128 (regno);
          out_uleb128 (offset);
        }
      break;

    case DW_CFA_register:
      out_one (DW_CFA_register);
      out_uleb128 (insn->u.rr.reg1);
      out_uleb128 (insn->u.rr.reg2);
      break;

    case DW_CFA_remember_state:
    case DW_CFA_restore_state:
      out_one (insn->insn);
      break;

    case DW_CFA_GNU_window_save:
      out_one (DW_CFA_GNU_window_save);
      break;

    case CFI_escape:
      {
        struct cfi_escape_data *e;
        for (e = insn->u.esc; e ; e = e->next)
          emit_expr (&e->exp, 1);
        break;
      }

    case CFI_val_encoded_addr:
      {
        unsigned encoding = insn->u.ea.encoding;
        offsetT encoding_size;

        if (encoding == DW_EH_PE_omit)
          break;
        out_one (DW_CFA_val_expression);
        out_uleb128 (insn->u.ea.reg);

        switch (encoding & 0x7)
          {
          case DW_EH_PE_absptr:
            encoding_size = DWARF2_ADDR_SIZE (stdoutput);
            break;
          case DW_EH_PE_udata2:
            encoding_size = 2;
            break;
          case DW_EH_PE_udata4:
            encoding_size = 4;
            break;
          case DW_EH_PE_udata8:
            encoding_size = 8;
            break;
          default:
            abort ();
          }

        /* If the user has requested absolute encoding,
           then use the smaller DW_OP_addr encoding.  */
        if (insn->u.ea.encoding == DW_EH_PE_absptr)
          {
            out_uleb128 (1 + encoding_size);
            out_one (DW_OP_addr);
          }
        else
          {
            out_uleb128 (1 + 1 + encoding_size);
            out_one (DW_OP_GNU_encoded_addr);
            out_one (encoding);

            if ((encoding & 0x70) == DW_EH_PE_pcrel)
              {
#if CFI_DIFF_EXPR_OK
                insn->u.ea.exp.X_op = O_subtract;
                insn->u.ea.exp.X_op_symbol = symbol_temp_new_now ();
#elif defined (tc_cfi_emit_pcrel_expr)
                tc_cfi_emit_pcrel_expr (&insn->u.ea.exp, encoding_size);
                break;
#else
                abort ();
#endif
              }
          }
        emit_expr (&insn->u.ea.exp, encoding_size);
      }
      break;

    case CFI_label:
      colon (insn->u.sym_name);
      break;

    default:
      abort ();
    }
}

static offsetT
encoding_size (unsigned char encoding)
{
  if (encoding == DW_EH_PE_omit)
    return 0;
  switch (encoding & 0x7)
    {
    case 0:
      return bfd_get_arch_size (stdoutput) == 64 ? 8 : 4;
    case DW_EH_PE_udata2:
      return 2;
    case DW_EH_PE_udata4:
      return 4;
    case DW_EH_PE_udata8:
      return 8;
    default:
      abort ();
    }
}

static void
output_cie (struct cie_entry *cie, bfd_boolean eh_frame, int align)
{
  symbolS *after_size_address, *end_address;
  expressionS exp;
  struct cfi_insn_data *i;
  offsetT augmentation_size;
  int enc;
  enum dwarf2_format fmt = DWARF2_FORMAT (now_seg);

  cie->start_address = symbol_temp_new_now ();
  after_size_address = symbol_temp_make ();
  end_address = symbol_temp_make ();

  exp.X_op = O_subtract;
  exp.X_add_symbol = end_address;
  exp.X_op_symbol = after_size_address;
  exp.X_add_number = 0;

  if (eh_frame || fmt == dwarf2_format_32bit)
    emit_expr (&exp, 4);                        /* Length.  */
  else
    {
      if (fmt == dwarf2_format_64bit)
        out_four (-1);
      emit_expr (&exp, 8);                      /* Length.  */
    }
  symbol_set_value_now (after_size_address);
  if (eh_frame)
    out_four (0);                               /* CIE id.  */
  else
    {
      out_four (-1);                            /* CIE id.  */
      if (fmt != dwarf2_format_32bit)
        out_four (-1);
    }
  out_one (DW_CIE_VERSION);                     /* Version.  */
  if (eh_frame)
    {
      out_one ('z');                            /* Augmentation.  */
      if (cie->per_encoding != DW_EH_PE_omit)
        out_one ('P');
      if (cie->lsda_encoding != DW_EH_PE_omit)
        out_one ('L');
      out_one ('R');
    }
  if (cie->signal_frame)
    out_one ('S');
  out_one (0);
  out_uleb128 (DWARF2_LINE_MIN_INSN_LENGTH);    /* Code alignment.  */
  out_sleb128 (DWARF2_CIE_DATA_ALIGNMENT);      /* Data alignment.  */
  if (DW_CIE_VERSION == 1)                      /* Return column.  */
    out_one (cie->return_column);
  else
    out_uleb128 (cie->return_column);
  if (eh_frame)
    {
      augmentation_size = 1 + (cie->lsda_encoding != DW_EH_PE_omit);
      if (cie->per_encoding != DW_EH_PE_omit)
        augmentation_size += 1 + encoding_size (cie->per_encoding);
      out_uleb128 (augmentation_size);          /* Augmentation size.  */

      if (cie->per_encoding != DW_EH_PE_omit)
        {
          offsetT size = encoding_size (cie->per_encoding);
          out_one (cie->per_encoding);
          exp = cie->personality;
          if ((cie->per_encoding & 0x70) == DW_EH_PE_pcrel)
            {
#if CFI_DIFF_EXPR_OK
              exp.X_op = O_subtract;
              exp.X_op_symbol = symbol_temp_new_now ();
              emit_expr (&exp, size);
#elif defined (tc_cfi_emit_pcrel_expr)
              tc_cfi_emit_pcrel_expr (&exp, size);
#else
              abort ();
#endif
            }
          else
            emit_expr (&exp, size);
        }

      if (cie->lsda_encoding != DW_EH_PE_omit)
        out_one (cie->lsda_encoding);
    }

  switch (DWARF2_FDE_RELOC_SIZE)
    {
    case 2:
      enc = DW_EH_PE_sdata2;
      break;
    case 4:
      enc = DW_EH_PE_sdata4;
      break;
    case 8:
      enc = DW_EH_PE_sdata8;
      break;
    default:
      abort ();
    }
#if CFI_DIFF_EXPR_OK || defined tc_cfi_emit_pcrel_expr
  enc |= DW_EH_PE_pcrel;
#endif
  if (eh_frame)
    out_one (enc);

  if (cie->first)
    {
      for (i = cie->first; i != cie->last; i = i->next)
        {
          if (CUR_SEG (i) != CUR_SEG (cie))
            continue;
          output_cfi_insn (i);
        }
    }

  frag_align (align, DW_CFA_nop, 0);
  symbol_set_value_now (end_address);
}

static void
output_fde (struct fde_entry *fde, struct cie_entry *cie,
            bfd_boolean eh_frame, struct cfi_insn_data *first,
            int align)
{
  symbolS *after_size_address, *end_address;
  expressionS exp;
  offsetT augmentation_size;
  enum dwarf2_format fmt = DWARF2_FORMAT (now_seg);
  int offset_size;
  int addr_size;

  after_size_address = symbol_temp_make ();
  end_address = symbol_temp_make ();

  exp.X_op = O_subtract;
  exp.X_add_symbol = end_address;
  exp.X_op_symbol = after_size_address;
  exp.X_add_number = 0;
  if (eh_frame || fmt == dwarf2_format_32bit)
    offset_size = 4;
  else
    {
      if (fmt == dwarf2_format_64bit)
        out_four (-1);
      offset_size = 8;
    }
  emit_expr (&exp, offset_size);                /* Length.  */
  symbol_set_value_now (after_size_address);

  if (eh_frame)
    {
      exp.X_op = O_subtract;
      exp.X_add_symbol = after_size_address;
      exp.X_op_symbol = cie->start_address;
      exp.X_add_number = 0;
      emit_expr (&exp, offset_size);            /* CIE offset.  */
    }
  else
    {
      TC_DWARF2_EMIT_OFFSET (cie->start_address, offset_size);
    }

  if (eh_frame)
    {
      exp.X_op = O_subtract;
      exp.X_add_number = 0;
#if CFI_DIFF_EXPR_OK
      exp.X_add_symbol = fde->start_address;
      exp.X_op_symbol = symbol_temp_new_now ();
      emit_expr (&exp, DWARF2_FDE_RELOC_SIZE);  /* Code offset.  */
#else
      exp.X_op = O_symbol;
      exp.X_add_symbol = fde->start_address;
#ifdef tc_cfi_emit_pcrel_expr
      tc_cfi_emit_pcrel_expr (&exp, DWARF2_FDE_RELOC_SIZE);      /* Code offset.  */
#else
      emit_expr (&exp, DWARF2_FDE_RELOC_SIZE);  /* Code offset.  */
#endif
#endif
      addr_size = DWARF2_FDE_RELOC_SIZE;
    }
  else
    {
      exp.X_op = O_symbol;
      exp.X_add_symbol = fde->start_address;
      exp.X_add_number = 0;
      addr_size = DWARF2_ADDR_SIZE (stdoutput);
      emit_expr (&exp, addr_size);
    }

  exp.X_op = O_subtract;
  exp.X_add_symbol = fde->end_address;
  exp.X_op_symbol = fde->start_address;         /* Code length.  */
  exp.X_add_number = 0;
  emit_expr (&exp, addr_size);

  augmentation_size = encoding_size (fde->lsda_encoding);
  if (eh_frame)
    out_uleb128 (augmentation_size);            /* Augmentation size.  */

  if (fde->lsda_encoding != DW_EH_PE_omit)
    {
      exp = fde->lsda;
      if ((fde->lsda_encoding & 0x70) == DW_EH_PE_pcrel)
        {
#if CFI_DIFF_LSDA_OK
          exp.X_op = O_subtract;
          exp.X_op_symbol = symbol_temp_new_now ();
          emit_expr (&exp, augmentation_size);
#elif defined (tc_cfi_emit_pcrel_expr)
          tc_cfi_emit_pcrel_expr (&exp, augmentation_size);
#else
          abort ();
#endif
        }
      else
        emit_expr (&exp, augmentation_size);
    }

  for (; first; first = first->next)
    if (CUR_SEG (first) == CUR_SEG (fde))
      output_cfi_insn (first);

  frag_align (align, DW_CFA_nop, 0);
  symbol_set_value_now (end_address);
}

static struct cie_entry *
select_cie_for_fde (struct fde_entry *fde, bfd_boolean eh_frame,
                    struct cfi_insn_data **pfirst, int align)
{
  struct cfi_insn_data *i, *j;
  struct cie_entry *cie;

  for (cie = cie_root; cie; cie = cie->next)
    {
      if (CUR_SEG (cie) != CUR_SEG (fde))
        continue;
      if (cie->return_column != fde->return_column
          || cie->signal_frame != fde->signal_frame
          || cie->per_encoding != fde->per_encoding
          || cie->lsda_encoding != fde->lsda_encoding)
        continue;
      if (cie->per_encoding != DW_EH_PE_omit)
        {
          if (cie->personality.X_op != fde->personality.X_op
              || cie->personality.X_add_number
                 != fde->personality.X_add_number)
            continue;
          switch (cie->personality.X_op)
            {
            case O_constant:
              if (cie->personality.X_unsigned != fde->personality.X_unsigned)
                continue;
              break;
            case O_symbol:
              if (cie->personality.X_add_symbol
                  != fde->personality.X_add_symbol)
                continue;
              break;
            default:
              abort ();
            }
        }
      for (i = cie->first, j = fde->data;
           i != cie->last && j != NULL;
           i = i->next, j = j->next)
        {
          if (i->insn != j->insn)
            goto fail;
          switch (i->insn)
            {
            case DW_CFA_advance_loc:
            case DW_CFA_remember_state:
              /* We reached the first advance/remember in the FDE,
                 but did not reach the end of the CIE list.  */
              goto fail;

            case DW_CFA_offset:
            case DW_CFA_def_cfa:
              if (i->u.ri.reg != j->u.ri.reg)
                goto fail;
              if (i->u.ri.offset != j->u.ri.offset)
                goto fail;
              break;

            case DW_CFA_register:
              if (i->u.rr.reg1 != j->u.rr.reg1)
                goto fail;
              if (i->u.rr.reg2 != j->u.rr.reg2)
                goto fail;
              break;

            case DW_CFA_def_cfa_register:
            case DW_CFA_restore:
            case DW_CFA_undefined:
            case DW_CFA_same_value:
              if (i->u.r != j->u.r)
                goto fail;
              break;

            case DW_CFA_def_cfa_offset:
              if (i->u.i != j->u.i)
                goto fail;
              break;

            case CFI_escape:
            case CFI_val_encoded_addr:
            case CFI_label:
              /* Don't bother matching these for now.  */
              goto fail;

            default:
              abort ();
            }
        }

      /* Success if we reached the end of the CIE list, and we've either
         run out of FDE entries or we've encountered an advance,
         remember, or escape.  */
      if (i == cie->last
          && (!j
              || j->insn == DW_CFA_advance_loc
              || j->insn == DW_CFA_remember_state
              || j->insn == CFI_escape
              || j->insn == CFI_val_encoded_addr
              || j->insn == CFI_label))
        {
          *pfirst = j;
          return cie;
        }

    fail:;
    }

  cie = (struct cie_entry *) xmalloc (sizeof (struct cie_entry));
  cie->next = cie_root;
  cie_root = cie;
  SET_CUR_SEG (cie, CUR_SEG (fde));
  cie->return_column = fde->return_column;
  cie->signal_frame = fde->signal_frame;
  cie->per_encoding = fde->per_encoding;
  cie->lsda_encoding = fde->lsda_encoding;
  cie->personality = fde->personality;
  cie->first = fde->data;

  for (i = cie->first; i ; i = i->next)
    if (i->insn == DW_CFA_advance_loc
        || i->insn == DW_CFA_remember_state
        || i->insn == CFI_escape
        || i->insn == CFI_val_encoded_addr
        || i->insn == CFI_label)
      break;

  cie->last = i;
  *pfirst = i;

  output_cie (cie, eh_frame, align);

  return cie;
}

#ifdef md_reg_eh_frame_to_debug_frame
static void
cfi_change_reg_numbers (struct cfi_insn_data *insn, segT ccseg)
{
  for (; insn; insn = insn->next)
    {
      if (CUR_SEG (insn) != ccseg)
        continue;
      switch (insn->insn)
        {
        case DW_CFA_advance_loc:
        case DW_CFA_def_cfa_offset:
        case DW_CFA_remember_state:
        case DW_CFA_restore_state:
        case DW_CFA_GNU_window_save:
        case CFI_escape:
        case CFI_label:
          break;

        case DW_CFA_def_cfa:
        case DW_CFA_offset:
          insn->u.ri.reg = md_reg_eh_frame_to_debug_frame (insn->u.ri.reg);
          break;

        case DW_CFA_def_cfa_register:
        case DW_CFA_undefined:
        case DW_CFA_same_value:
        case DW_CFA_restore:
          insn->u.r = md_reg_eh_frame_to_debug_frame (insn->u.r);
          break;

        case DW_CFA_register:
          insn->u.rr.reg1 = md_reg_eh_frame_to_debug_frame (insn->u.rr.reg1);
          insn->u.rr.reg2 = md_reg_eh_frame_to_debug_frame (insn->u.rr.reg2);
          break;

        case CFI_val_encoded_addr:
          insn->u.ea.reg = md_reg_eh_frame_to_debug_frame (insn->u.ea.reg);
          break;

        default:
          abort ();
        }
    }
}
#else
#define cfi_change_reg_numbers(insn, cseg) do { } while (0)
#endif

static segT
get_cfi_seg (segT cseg, const char *base, flagword flags, int align)
{
  if (SUPPORT_FRAME_LINKONCE)
    {
      struct dwcfi_seg_list *l;

      l = dwcfi_hash_find_or_make (cseg, base, flags);

      cseg = l->seg;
      subseg_set (cseg, l->subseg);
    }
  else
    {
      cseg = subseg_new (base, 0);
      bfd_set_section_flags (stdoutput, cseg, flags);
    }
  record_alignment (cseg, align);
  return cseg;
}

void
cfi_finish (void)
{
  struct cie_entry *cie, *cie_next;
  segT cfi_seg, ccseg;
  struct fde_entry *fde;
  struct cfi_insn_data *first;
  int save_flag_traditional_format, seek_next_seg;

  if (all_fde_data == 0)
    return;

  if ((cfi_sections & CFI_EMIT_eh_frame) != 0)
    {
      /* Make sure check_eh_frame doesn't do anything with our output.  */
      save_flag_traditional_format = flag_traditional_format;
      flag_traditional_format = 1;

      if (!SUPPORT_FRAME_LINKONCE)
        {
          /* Open .eh_frame section.  */
          cfi_seg = get_cfi_seg (NULL, ".eh_frame",
                                 (SEC_ALLOC | SEC_LOAD | SEC_DATA
                                  | DWARF2_EH_FRAME_READ_ONLY),
                                 EH_FRAME_ALIGNMENT);
#ifdef md_fix_up_eh_frame
          md_fix_up_eh_frame (cfi_seg);
#else
          (void) cfi_seg;
#endif
        }

      do
        {
          ccseg = NULL;
          seek_next_seg = 0;

          for (cie = cie_root; cie; cie = cie_next)
            {
              cie_next = cie->next;
              free ((void *) cie);
            }
          cie_root = NULL;

          for (fde = all_fde_data; fde ; fde = fde->next)
            {
              if (SUPPORT_FRAME_LINKONCE)
                {
                  if (HANDLED (fde))
                    continue;
                  if (seek_next_seg && CUR_SEG (fde) != ccseg)
                    {
                      seek_next_seg = 2;
                      continue;
                    }
                  if (!seek_next_seg)
                    {
                      ccseg = CUR_SEG (fde);
                      /* Open .eh_frame section.  */
                      cfi_seg = get_cfi_seg (ccseg, ".eh_frame",
                                             (SEC_ALLOC | SEC_LOAD | SEC_DATA
                                              | DWARF2_EH_FRAME_READ_ONLY),
                                             EH_FRAME_ALIGNMENT);
#ifdef md_fix_up_eh_frame
                      md_fix_up_eh_frame (cfi_seg);
#else
                      (void) cfi_seg;
#endif
                      seek_next_seg = 1;
                    }
                  SET_HANDLED (fde, 1);
                }

              if (fde->end_address == NULL)
                {
                  as_bad (_("open CFI at the end of file; missing .cfi_endproc directive"));
                  fde->end_address = fde->start_address;
                }

              cie = select_cie_for_fde (fde, TRUE, &first, 2);
              output_fde (fde, cie, TRUE, first,
                          fde->next == NULL ? EH_FRAME_ALIGNMENT : 2);
            }
        }
      while (SUPPORT_FRAME_LINKONCE && seek_next_seg == 2);

      if (SUPPORT_FRAME_LINKONCE)
        for (fde = all_fde_data; fde ; fde = fde->next)
          SET_HANDLED (fde, 0);

      flag_traditional_format = save_flag_traditional_format;
    }

  if ((cfi_sections & CFI_EMIT_debug_frame) != 0)
    {
      int alignment = ffs (DWARF2_ADDR_SIZE (stdoutput)) - 1;

      if (!SUPPORT_FRAME_LINKONCE)
        get_cfi_seg (NULL, ".debug_frame",
                     SEC_READONLY | SEC_DEBUGGING,
                     alignment);

      do
        {
          ccseg = NULL;
          seek_next_seg = 0;

          for (cie = cie_root; cie; cie = cie_next)
            {
              cie_next = cie->next;
              free ((void *) cie);
            }
          cie_root = NULL;

          for (fde = all_fde_data; fde ; fde = fde->next)
            {
              if (SUPPORT_FRAME_LINKONCE)
                {
                  if (HANDLED (fde))
                    continue;
                  if (seek_next_seg && CUR_SEG (fde) != ccseg)
                    {
                      seek_next_seg = 2;
                      continue;
                    }
                  if (!seek_next_seg)
                    {
                      ccseg = CUR_SEG (fde);
                      /* Open .debug_frame section.  */
                      get_cfi_seg (ccseg, ".debug_frame",
                                   SEC_READONLY | SEC_DEBUGGING,
                                   alignment);
                      seek_next_seg = 1;
                    }
                  SET_HANDLED (fde, 1);
                }
              if (fde->end_address == NULL)
                {
                  as_bad (_("open CFI at the end of file; missing .cfi_endproc directive"));
                  fde->end_address = fde->start_address;
                }

              fde->per_encoding = DW_EH_PE_omit;
              fde->lsda_encoding = DW_EH_PE_omit;
              cfi_change_reg_numbers (fde->data, ccseg);
              cie = select_cie_for_fde (fde, FALSE, &first, alignment);
              output_fde (fde, cie, FALSE, first, alignment);
            }
        }
      while (SUPPORT_FRAME_LINKONCE && seek_next_seg == 2);

      if (SUPPORT_FRAME_LINKONCE)
        for (fde = all_fde_data; fde ; fde = fde->next)
          SET_HANDLED (fde, 0);
    }
}

#else /* TARGET_USE_CFIPOP */

/* Emit an intelligible error message for missing support.  */

static void
dot_cfi_dummy (int ignored ATTRIBUTE_UNUSED)
{
  as_bad (_("CFI is not supported for this target"));
  ignore_rest_of_line ();
}

const pseudo_typeS cfi_pseudo_table[] =
  {
    { "cfi_sections", dot_cfi_dummy, 0 },
    { "cfi_startproc", dot_cfi_dummy, 0 },
    { "cfi_endproc", dot_cfi_dummy, 0 },
    { "cfi_def_cfa", dot_cfi_dummy, 0 },
    { "cfi_def_cfa_register", dot_cfi_dummy, 0 },
    { "cfi_def_cfa_offset", dot_cfi_dummy, 0 },
    { "cfi_adjust_cfa_offset", dot_cfi_dummy, 0 },
    { "cfi_offset", dot_cfi_dummy, 0 },
    { "cfi_rel_offset", dot_cfi_dummy, 0 },
    { "cfi_register", dot_cfi_dummy, 0 },
    { "cfi_return_column", dot_cfi_dummy, 0 },
    { "cfi_restore", dot_cfi_dummy, 0 },
    { "cfi_undefined", dot_cfi_dummy, 0 },
    { "cfi_same_value", dot_cfi_dummy, 0 },
    { "cfi_remember_state", dot_cfi_dummy, 0 },
    { "cfi_restore_state", dot_cfi_dummy, 0 },
    { "cfi_window_save", dot_cfi_dummy, 0 },
    { "cfi_escape", dot_cfi_dummy, 0 },
    { "cfi_signal_frame", dot_cfi_dummy, 0 },
    { "cfi_personality", dot_cfi_dummy, 0 },
    { "cfi_lsda", dot_cfi_dummy, 0 },
    { "cfi_val_encoded_addr", dot_cfi_dummy, 0 },
    { "cfi_label", dot_cfi_dummy, 0 },
    { NULL, NULL, 0 }
  };

void
cfi_finish (void)
{
}
#endif /* TARGET_USE_CFIPOP */