gcc/dwarf2out.h

   1 /* dwarf2out.h - Various declarations for functions found in dwarf2out.c
   2    Copyright (C) 1998-2021 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef GCC_DWARF2OUT_H
  21 #define GCC_DWARF2OUT_H 1
  22
  23 #include "dwarf2.h"     /* ??? Remove this once only used by dwarf2foo.c.  */
  24
  25 typedef struct die_struct *dw_die_ref;
  26 typedef const struct die_struct *const_dw_die_ref;
  27
  28 typedef struct dw_val_node *dw_val_ref;
  29 typedef struct dw_cfi_node *dw_cfi_ref;
  30 typedef struct dw_loc_descr_node *dw_loc_descr_ref;
  31 typedef struct dw_loc_list_struct *dw_loc_list_ref;
  32 typedef struct dw_discr_list_node *dw_discr_list_ref;
  33 typedef wide_int *wide_int_ptr;
  34
  35
  36 /* Call frames are described using a sequence of Call Frame
  37    Information instructions.  The register number, offset
  38    and address fields are provided as possible operands;
  39    their use is selected by the opcode field.  */
  40
  41 enum dw_cfi_oprnd_type {
  42   dw_cfi_oprnd_unused,
  43   dw_cfi_oprnd_reg_num,
  44   dw_cfi_oprnd_offset,
  45   dw_cfi_oprnd_addr,
  46   dw_cfi_oprnd_loc,
  47   dw_cfi_oprnd_cfa_loc
  48 };
  49
  50 typedef union GTY(()) {
  51   unsigned int GTY ((tag ("dw_cfi_oprnd_reg_num"))) dw_cfi_reg_num;
  52   HOST_WIDE_INT GTY ((tag ("dw_cfi_oprnd_offset"))) dw_cfi_offset;
  53   const char * GTY ((tag ("dw_cfi_oprnd_addr"))) dw_cfi_addr;
  54   struct dw_loc_descr_node * GTY ((tag ("dw_cfi_oprnd_loc"))) dw_cfi_loc;
  55   struct dw_cfa_location * GTY ((tag ("dw_cfi_oprnd_cfa_loc")))
  56     dw_cfi_cfa_loc;
  57 } dw_cfi_oprnd;
  58
  59 struct GTY(()) dw_cfi_node {
  60   enum dwarf_call_frame_info dw_cfi_opc;
  61   dw_cfi_oprnd GTY ((desc ("dw_cfi_oprnd1_desc (%1.dw_cfi_opc)")))
  62     dw_cfi_oprnd1;
  63   dw_cfi_oprnd GTY ((desc ("dw_cfi_oprnd2_desc (%1.dw_cfi_opc)")))
  64     dw_cfi_oprnd2;
  65 };
  66
  67
  68 typedef vec<dw_cfi_ref, va_gc> *cfi_vec;
  69
  70 typedef struct dw_fde_node *dw_fde_ref;
  71
  72 /* All call frame descriptions (FDE's) in the GCC generated DWARF
  73    refer to a single Common Information Entry (CIE), defined at
  74    the beginning of the .debug_frame section.  This use of a single
  75    CIE obviates the need to keep track of multiple CIE's
  76    in the DWARF generation routines below.  */
  77
  78 struct GTY(()) dw_fde_node {
  79   tree decl;
  80   const char *dw_fde_begin;
  81   const char *dw_fde_current_label;
  82   const char *dw_fde_end;
  83   const char *dw_fde_vms_end_prologue;
  84   const char *dw_fde_vms_begin_epilogue;
  85   const char *dw_fde_second_begin;
  86   const char *dw_fde_second_end;
  87   cfi_vec dw_fde_cfi;
  88   int dw_fde_switch_cfi_index; /* Last CFI before switching sections.  */
  89   HOST_WIDE_INT stack_realignment;
  90
  91   unsigned funcdef_number;
  92   unsigned fde_index;
  93
  94   /* Dynamic realign argument pointer register.  */
  95   unsigned int drap_reg;
  96   /* Virtual dynamic realign argument pointer register.  */
  97   unsigned int vdrap_reg;
  98   /* These 3 flags are copied from rtl_data in function.h.  */
  99   unsigned all_throwers_are_sibcalls : 1;
 100   unsigned uses_eh_lsda : 1;
 101   unsigned nothrow : 1;
 102   /* Whether we did stack realign in this call frame.  */
 103   unsigned stack_realign : 1;
 104   /* Whether dynamic realign argument pointer register has been saved.  */
 105   unsigned drap_reg_saved: 1;
 106   /* True iff dw_fde_begin label is in text_section or cold_text_section.  */
 107   unsigned in_std_section : 1;
 108   /* True iff dw_fde_second_begin label is in text_section or
 109      cold_text_section.  */
 110   unsigned second_in_std_section : 1;
 111 };
 112
 113
 114 /* This is how we define the location of the CFA. We use to handle it
 115    as REG + OFFSET all the time,  but now it can be more complex.
 116    It can now be either REG + CFA_OFFSET or *(REG + BASE_OFFSET) + CFA_OFFSET.
 117    Instead of passing around REG and OFFSET, we pass a copy
 118    of this structure.  */
 119 struct GTY(()) dw_cfa_location {
 120   poly_int64_pod offset;
 121   poly_int64_pod base_offset;
 122   /* REG is in DWARF_FRAME_REGNUM space, *not* normal REGNO space.  */
 123   unsigned int reg;
 124   BOOL_BITFIELD indirect : 1;  /* 1 if CFA is accessed via a dereference.  */
 125   BOOL_BITFIELD in_use : 1;    /* 1 if a saved cfa is stored here.  */
 126 };
 127
 128
 129 /* Each DIE may have a series of attribute/value pairs.  Values
 130    can take on several forms.  The forms that are used in this
 131    implementation are listed below.  */
 132
 133 enum dw_val_class
 134 {
 135   dw_val_class_none,
 136   dw_val_class_addr,
 137   dw_val_class_offset,
 138   dw_val_class_loc,
 139   dw_val_class_loc_list,
 140   dw_val_class_range_list,
 141   dw_val_class_const,
 142   dw_val_class_unsigned_const,
 143   dw_val_class_const_double,
 144   dw_val_class_wide_int,
 145   dw_val_class_vec,
 146   dw_val_class_flag,
 147   dw_val_class_die_ref,
 148   dw_val_class_fde_ref,
 149   dw_val_class_lbl_id,
 150   dw_val_class_lineptr,
 151   dw_val_class_str,
 152   dw_val_class_macptr,
 153   dw_val_class_loclistsptr,
 154   dw_val_class_file,
 155   dw_val_class_data8,
 156   dw_val_class_decl_ref,
 157   dw_val_class_vms_delta,
 158   dw_val_class_high_pc,
 159   dw_val_class_discr_value,
 160   dw_val_class_discr_list,
 161   dw_val_class_const_implicit,
 162   dw_val_class_unsigned_const_implicit,
 163   dw_val_class_file_implicit,
 164   dw_val_class_view_list,
 165   dw_val_class_symview
 166 };
 167
 168 /* Describe a floating point constant value, or a vector constant value.  */
 169
 170 struct GTY(()) dw_vec_const {
 171   void * GTY((atomic)) array;
 172   unsigned length;
 173   unsigned elt_size;
 174 };
 175
 176 /* Describe a single value that a discriminant can match.
 177
 178    Discriminants (in the "record variant part" meaning) are scalars.
 179    dw_discr_list_ref and dw_discr_value are a mean to describe a set of
 180    discriminant values that are matched by a particular variant.
 181
 182    Discriminants can be signed or unsigned scalars, and can be discriminants
 183    values.  Both have to be consistent, though.  */
 184
 185 struct GTY(()) dw_discr_value {
 186   int pos; /* Whether the discriminant value is positive (unsigned).  */
 187   union
 188     {
 189       HOST_WIDE_INT GTY ((tag ("0"))) sval;
 190       unsigned HOST_WIDE_INT GTY ((tag ("1"))) uval;
 191     }
 192   GTY ((desc ("%1.pos"))) v;
 193 };
 194
 195 struct addr_table_entry;
 196
 197 /* The dw_val_node describes an attribute's value, as it is
 198    represented internally.  */
 199
 200 struct GTY(()) dw_val_node {
 201   enum dw_val_class val_class;
 202   struct addr_table_entry * GTY(()) val_entry;
 203   union dw_val_struct_union
 204     {
 205       rtx GTY ((tag ("dw_val_class_addr"))) val_addr;
 206       unsigned HOST_WIDE_INT GTY ((tag ("dw_val_class_offset"))) val_offset;
 207       dw_loc_list_ref GTY ((tag ("dw_val_class_loc_list"))) val_loc_list;
 208       dw_die_ref GTY ((tag ("dw_val_class_view_list"))) val_view_list;
 209       dw_loc_descr_ref GTY ((tag ("dw_val_class_loc"))) val_loc;
 210       HOST_WIDE_INT GTY ((default)) val_int;
 211       unsigned HOST_WIDE_INT
 212         GTY ((tag ("dw_val_class_unsigned_const"))) val_unsigned;
 213       double_int GTY ((tag ("dw_val_class_const_double"))) val_double;
 214       wide_int_ptr GTY ((tag ("dw_val_class_wide_int"))) val_wide;
 215       dw_vec_const GTY ((tag ("dw_val_class_vec"))) val_vec;
 216       struct dw_val_die_union
 217         {
 218           dw_die_ref die;
 219           int external;
 220         } GTY ((tag ("dw_val_class_die_ref"))) val_die_ref;
 221       unsigned GTY ((tag ("dw_val_class_fde_ref"))) val_fde_index;
 222       struct indirect_string_node * GTY ((tag ("dw_val_class_str"))) val_str;
 223       char * GTY ((tag ("dw_val_class_lbl_id"))) val_lbl_id;
 224       unsigned char GTY ((tag ("dw_val_class_flag"))) val_flag;
 225       struct dwarf_file_data * GTY ((tag ("dw_val_class_file"))) val_file;
 226       struct dwarf_file_data *
 227         GTY ((tag ("dw_val_class_file_implicit"))) val_file_implicit;
 228       unsigned char GTY ((tag ("dw_val_class_data8"))) val_data8[8];
 229       tree GTY ((tag ("dw_val_class_decl_ref"))) val_decl_ref;
 230       struct dw_val_vms_delta_union
 231         {
 232           char * lbl1;
 233           char * lbl2;
 234         } GTY ((tag ("dw_val_class_vms_delta"))) val_vms_delta;
 235       dw_discr_value GTY ((tag ("dw_val_class_discr_value"))) val_discr_value;
 236       dw_discr_list_ref GTY ((tag ("dw_val_class_discr_list"))) val_discr_list;
 237       char * GTY ((tag ("dw_val_class_symview"))) val_symbolic_view;
 238     }
 239   GTY ((desc ("%1.val_class"))) v;
 240 };
 241
 242 /* Locations in memory are described using a sequence of stack machine
 243    operations.  */
 244
 245 struct GTY((chain_next ("%h.dw_loc_next"))) dw_loc_descr_node {
 246   dw_loc_descr_ref dw_loc_next;
 247   ENUM_BITFIELD (dwarf_location_atom) dw_loc_opc : 8;
 248   /* Used to distinguish DW_OP_addr with a direct symbol relocation
 249      from DW_OP_addr with a dtp-relative symbol relocation.  */
 250   unsigned int dtprel : 1;
 251   /* For DW_OP_pick, DW_OP_dup and DW_OP_over operations: true iff.
 252      it targets a DWARF prodecure argument.  In this case, it needs to be
 253      relocated according to the current frame offset.  */
 254   unsigned int frame_offset_rel : 1;
 255   int dw_loc_addr;
 256   dw_val_node dw_loc_oprnd1;
 257   dw_val_node dw_loc_oprnd2;
 258 };
 259
 260 /* A variant (inside a record variant part) is selected when the corresponding
 261    discriminant matches its set of values (see the comment for dw_discr_value).
 262    The following datastructure holds such matching information.  */
 263
 264 struct GTY(()) dw_discr_list_node {
 265   dw_discr_list_ref dw_discr_next;
 266
 267   dw_discr_value dw_discr_lower_bound;
 268   dw_discr_value dw_discr_upper_bound;
 269   /* This node represents only the value in dw_discr_lower_bound when it's
 270      zero.  It represents the range between the two fields (bounds included)
 271      otherwise.  */
 272   int dw_discr_range;
 273 };
 274
 275 /* Interface from dwarf2out.c to dwarf2cfi.c.  */
 276 extern struct dw_loc_descr_node *build_cfa_loc
 277   (dw_cfa_location *, poly_int64);
 278 extern struct dw_loc_descr_node *build_cfa_aligned_loc
 279   (dw_cfa_location *, poly_int64, HOST_WIDE_INT);
 280 extern struct dw_loc_descr_node *mem_loc_descriptor
 281   (rtx, machine_mode mode, machine_mode mem_mode,
 282    enum var_init_status);
 283 extern bool loc_descr_equal_p (dw_loc_descr_ref, dw_loc_descr_ref);
 284 extern dw_fde_ref dwarf2out_alloc_current_fde (void);
 285
 286 extern unsigned long size_of_locs (dw_loc_descr_ref);
 287 extern void output_loc_sequence (dw_loc_descr_ref, int);
 288 extern void output_loc_sequence_raw (dw_loc_descr_ref);
 289
 290 /* Interface from dwarf2cfi.c to dwarf2out.c.  */
 291 extern void lookup_cfa_1 (dw_cfi_ref cfi, dw_cfa_location *loc,
 292                           dw_cfa_location *remember);
 293 extern bool cfa_equal_p (const dw_cfa_location *, const dw_cfa_location *);
 294
 295 extern void output_cfi (dw_cfi_ref, dw_fde_ref, int);
 296
 297 extern GTY(()) cfi_vec cie_cfi_vec;
 298
 299 /* Interface from dwarf2*.c to the rest of the compiler.  */
 300 extern enum dw_cfi_oprnd_type dw_cfi_oprnd1_desc
 301   (enum dwarf_call_frame_info cfi);
 302 extern enum dw_cfi_oprnd_type dw_cfi_oprnd2_desc
 303   (enum dwarf_call_frame_info cfi);
 304
 305 extern void output_cfi_directive (FILE *f, struct dw_cfi_node *cfi);
 306
 307 extern void dwarf2out_emit_cfi (dw_cfi_ref cfi);
 308
 309 extern void debug_dwarf (void);
 310 struct die_struct;
 311 extern void debug_dwarf_die (struct die_struct *);
 312 extern void debug_dwarf_loc_descr (dw_loc_descr_ref);
 313 extern void debug (die_struct &ref);
 314 extern void debug (die_struct *ptr);
 315 extern void dwarf2out_set_demangle_name_func (const char *(*) (const char *));
 316 #ifdef VMS_DEBUGGING_INFO
 317 extern void dwarf2out_vms_debug_main_pointer (void);
 318 #endif
 319
 320 enum array_descr_ordering
 321 {
 322   array_descr_ordering_default,
 323   array_descr_ordering_row_major,
 324   array_descr_ordering_column_major
 325 };
 326
 327 #define DWARF2OUT_ARRAY_DESCR_INFO_MAX_DIMEN 16
 328
 329 struct array_descr_info
 330 {
 331   int ndimensions;
 332   enum array_descr_ordering ordering;
 333   tree element_type;
 334   tree base_decl;
 335   tree data_location;
 336   tree allocated;
 337   tree associated;
 338   tree stride;
 339   tree rank;
 340   bool stride_in_bits;
 341   struct array_descr_dimen
 342     {
 343       /* GCC uses sizetype for array indices, so lower_bound and upper_bound
 344          will likely be "sizetype" values. However, bounds may have another
 345          type in the original source code.  */
 346       tree bounds_type;
 347       tree lower_bound;
 348       tree upper_bound;
 349
 350       /* Only Fortran uses more than one dimension for array types.  For other
 351          languages, the stride can be rather specified for the whole array.  */
 352       tree stride;
 353     } dimen[DWARF2OUT_ARRAY_DESCR_INFO_MAX_DIMEN];
 354 };
 355
 356 enum fixed_point_scale_factor
 357 {
 358   fixed_point_scale_factor_binary,
 359   fixed_point_scale_factor_decimal,
 360   fixed_point_scale_factor_arbitrary
 361 };
 362
 363 struct fixed_point_type_info
 364 {
 365   /* The scale factor is the value one has to multiply the actual data with
 366      to get the fixed point value.  We support three ways to encode it.  */
 367   enum fixed_point_scale_factor scale_factor_kind;
 368   union
 369     {
 370       /* For a binary scale factor, the scale factor is 2 ** binary.  */
 371       int binary;
 372       /* For a decimal scale factor, the scale factor is 10 ** decimal.  */
 373       int decimal;
 374       /* For an arbitrary scale factor, the scale factor is the ratio
 375          numerator / denominator.  */
 376       struct { tree numerator; tree denominator; } arbitrary;
 377     } scale_factor;
 378 };
 379
 380 void dwarf2out_c_finalize (void);
 381
 382 #endif /* GCC_DWARF2OUT_H */