gas/scfidw2gen.c

   1 /* scfidw2gen.c - Support for emission of synthesized Dwarf2 CFI.
   2    Copyright (C) 2023 Free Software Foundation, Inc.
   3
   4    This file is part of GAS, the GNU Assembler.
   5
   6    GAS is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3, or (at your option)
   9    any later version.
  10
  11    GAS is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with GAS; see the file COPYING.  If not, write to the Free
  18    Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
  19    02110-1301, USA.  */
  20
  21 #include "as.h"
  22 #include "ginsn.h"
  23 #include "scfi.h"
  24 #include "dw2gencfi.h"
  25 #include "subsegs.h"
  26 #include "scfidw2gen.h"
  27
  28 #if defined (TARGET_USE_SCFI) && defined (TARGET_USE_GINSN)
  29
  30 static bool scfi_ignore_warn_once;
  31
  32 static void
  33 dot_scfi_ignore (int ignored ATTRIBUTE_UNUSED)
  34 {
  35   gas_assert (flag_synth_cfi);
  36
  37   if (!scfi_ignore_warn_once)
  38     {
  39       as_warn (_("SCFI ignores most user-specified CFI directives"));
  40       scfi_ignore_warn_once = true;
  41     }
  42   ignore_rest_of_line ();
  43 }
  44
  45 static void
  46 scfi_process_cfi_label (void)
  47 {
  48   char *name;
  49   ginsnS *ginsn;
  50
  51   name = read_symbol_name ();
  52   if (name == NULL)
  53     return;
  54
  55   /* Add a new ginsn.  */
  56   ginsn = ginsn_new_phantom (symbol_temp_new_now ());
  57   frch_ginsn_data_append (ginsn);
  58
  59   scfi_op_add_cfi_label (ginsn, name);
  60   /* TODO.  */
  61   // free (name);
  62
  63   demand_empty_rest_of_line ();
  64 }
  65
  66 static void
  67 scfi_process_cfi_signal_frame (void)
  68 {
  69   ginsnS *ginsn;
  70
  71   ginsn = ginsn_new_phantom (symbol_temp_new_now ());
  72   frch_ginsn_data_append (ginsn);
  73
  74   scfi_op_add_signal_frame (ginsn);
  75 }
  76
  77 static void
  78 dot_scfi (int arg)
  79 {
  80   switch (arg)
  81     {
  82       case CFI_label:
  83         scfi_process_cfi_label ();
  84         break;
  85       case CFI_signal_frame:
  86         scfi_process_cfi_signal_frame ();
  87         break;
  88       default:
  89         abort ();
  90     }
  91 }
  92
  93 const pseudo_typeS scfi_pseudo_table[] =
  94   {
  95     { "cfi_sections", dot_cfi_sections, 0 }, /* No ignore.  */
  96     { "cfi_signal_frame", dot_scfi, CFI_signal_frame }, /* No ignore.  */
  97     { "cfi_label", dot_scfi, CFI_label }, /* No ignore.  */
  98     { "cfi_startproc", dot_scfi_ignore, 0 },
  99     { "cfi_endproc", dot_scfi_ignore, 0 },
 100     { "cfi_fde_data", dot_scfi_ignore, 0 },
 101     { "cfi_def_cfa", dot_scfi_ignore, 0 },
 102     { "cfi_def_cfa_register", dot_scfi_ignore, 0 },
 103     { "cfi_def_cfa_offset", dot_scfi_ignore, 0 },
 104     { "cfi_adjust_cfa_offset", dot_scfi_ignore, 0 },
 105     { "cfi_offset", dot_scfi_ignore, 0 },
 106     { "cfi_rel_offset", dot_scfi_ignore, 0 },
 107     { "cfi_register", dot_scfi_ignore, 0 },
 108     { "cfi_return_column", dot_scfi_ignore, 0 },
 109     { "cfi_restore", dot_scfi_ignore, 0 },
 110     { "cfi_undefined", dot_scfi_ignore, 0 },
 111     { "cfi_same_value", dot_scfi_ignore, 0 },
 112     { "cfi_remember_state", dot_scfi_ignore, 0 },
 113     { "cfi_restore_state", dot_scfi_ignore, 0 },
 114     { "cfi_window_save", dot_scfi_ignore, 0 },
 115     { "cfi_negate_ra_state", dot_scfi_ignore, 0 },
 116     { "cfi_escape", dot_scfi_ignore, 0 },
 117     { "cfi_personality", dot_scfi_ignore, 0 },
 118     { "cfi_personality_id", dot_scfi_ignore, 0 },
 119     { "cfi_lsda", dot_scfi_ignore, 0 },
 120     { "cfi_val_encoded_addr", dot_scfi_ignore, 0 },
 121     { "cfi_inline_lsda", dot_scfi_ignore, 0 },
 122     { "cfi_val_offset", dot_scfi_ignore, 0 },
 123     { NULL, NULL, 0 }
 124   };
 125
 126 void
 127 scfi_dot_cfi_startproc (const symbolS *start_sym)
 128 {
 129   if (frchain_now->frch_cfi_data != NULL)
 130     {
 131       as_bad (_("SCFI: missing previous SCFI endproc marker"));
 132       return;
 133     }
 134
 135   cfi_new_fde ((symbolS *)start_sym);
 136
 137   cfi_set_sections ();
 138
 139   frchain_now->frch_cfi_data->cur_cfa_offset = 0;
 140
 141   /* By default, SCFI machinery assumes .cfi_startproc is used without
 142      parameter simple.  */
 143   tc_cfi_frame_initial_instructions ();
 144
 145   if ((all_cfi_sections & CFI_EMIT_target) != 0)
 146     tc_cfi_startproc ();
 147 }
 148
 149 void
 150 scfi_dot_cfi_endproc (const symbolS *end_sym)
 151 {
 152   struct fde_entry *fde_last;
 153
 154   if (frchain_now->frch_cfi_data == NULL)
 155     {
 156       as_bad (_(".cfi_endproc without corresponding .cfi_startproc"));
 157       return;
 158     }
 159
 160   fde_last = frchain_now->frch_cfi_data->cur_fde_data;
 161   cfi_set_last_fde (fde_last);
 162
 163   cfi_end_fde ((symbolS *)end_sym);
 164
 165   if ((all_cfi_sections & CFI_EMIT_target) != 0)
 166     tc_cfi_endproc (fde_last);
 167 }
 168
 169 void
 170 scfi_dot_cfi (int arg, unsigned reg1, unsigned reg2, offsetT offset,
 171               const char *name, const symbolS *advloc)
 172 {
 173   if (frchain_now->frch_cfi_data == NULL)
 174     {
 175       as_bad (_("CFI instruction used without previous .cfi_startproc"));
 176       return;
 177     }
 178
 179   /* If the last address was not at the current PC, advance to current.  */
 180   if (frchain_now->frch_cfi_data->last_address != advloc)
 181     cfi_add_advance_loc ((symbolS *)advloc);
 182
 183   switch (arg)
 184     {
 185     case DW_CFA_offset:
 186       cfi_add_CFA_offset (reg1, offset);
 187       break;
 188
 189     case DW_CFA_val_offset:
 190       cfi_add_CFA_val_offset (reg1, offset);
 191       break;
 192
 193     case CFI_rel_offset:
 194       cfi_add_CFA_offset (reg1,
 195                           offset - frchain_now->frch_cfi_data->cur_cfa_offset);
 196       break;
 197
 198     case DW_CFA_def_cfa:
 199       cfi_add_CFA_def_cfa (reg1, offset);
 200       break;
 201
 202     case DW_CFA_register:
 203       cfi_add_CFA_register (reg1, reg2);
 204       break;
 205
 206     case DW_CFA_def_cfa_register:
 207       cfi_add_CFA_def_cfa_register (reg1);
 208       break;
 209
 210     case DW_CFA_def_cfa_offset:
 211       cfi_add_CFA_def_cfa_offset (offset);
 212       break;
 213
 214     case CFI_adjust_cfa_offset:
 215       cfi_add_CFA_def_cfa_offset (frchain_now->frch_cfi_data->cur_cfa_offset
 216                                   + offset);
 217       break;
 218
 219     case DW_CFA_restore:
 220       cfi_add_CFA_restore (reg1);
 221       break;
 222
 223     case DW_CFA_remember_state:
 224       cfi_add_CFA_remember_state ();
 225       break;
 226
 227     case DW_CFA_restore_state:
 228       cfi_add_CFA_restore_state ();
 229       break;
 230
 231     case CFI_label:
 232       cfi_add_label (name);
 233       break;
 234
 235     case CFI_signal_frame:
 236       frchain_now->frch_cfi_data->cur_fde_data->signal_frame = 1;
 237       break;
 238
 239 /*
 240     case DW_CFA_undefined:
 241       for (;;)
 242         {
 243           reg1 = cfi_parse_reg ();
 244           cfi_add_CFA_undefined (reg1);
 245           SKIP_WHITESPACE ();
 246           if (*input_line_pointer != ',')
 247             break;
 248           ++input_line_pointer;
 249         }
 250       break;
 251
 252     case DW_CFA_same_value:
 253       reg1 = cfi_parse_reg ();
 254       cfi_add_CFA_same_value (reg1);
 255       break;
 256
 257     case CFI_return_column:
 258       reg1 = cfi_parse_reg ();
 259       cfi_set_return_column (reg1);
 260       break;
 261
 262     case DW_CFA_GNU_window_save:
 263       cfi_add_CFA_insn (DW_CFA_GNU_window_save);
 264       break;
 265
 266 */
 267     default:
 268       abort ();
 269     }
 270 }
 271
 272 #endif