gcc/read-md.h

   1 /* MD reader definitions.
   2    Copyright (C) 1987-2023 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_READ_MD_H
  21 #define GCC_READ_MD_H
  22
  23 #include "obstack.h"
  24
  25 /* Records a position in the file.  */
  26 class file_location {
  27 public:
  28   file_location () {}
  29   file_location (const char *, int, int);
  30
  31   const char *filename;
  32   int lineno;
  33   int colno;
  34 };
  35
  36 inline file_location::file_location (const char *filename_in, int lineno_in, int colno_in)
  37 : filename (filename_in), lineno (lineno_in), colno (colno_in) {}
  38
  39 /* Holds one symbol or number in the .md file.  */
  40 struct md_name {
  41   /* The name as it appeared in the .md file.  Names are syntactically
  42      limited to the length of this buffer.  */
  43   char buffer[256];
  44
  45   /* The name that should actually be used by the generator programs.
  46      This is an expansion of NAME, after things like constant substitution.  */
  47   char *string;
  48 };
  49
  50 /* This structure represents a constant defined by define_constant,
  51    define_enum, or such-like.  */
  52 struct md_constant {
  53   /* The name of the constant.  */
  54   char *name;
  55
  56   /* The string to which the constants expands.  */
  57   char *value;
  58
  59   /* If the constant is associated with a enumeration, this field
  60      points to that enumeration, otherwise it is null.  */
  61   struct enum_type *parent_enum;
  62 };
  63
  64 /* This structure represents one value in an enum_type.  */
  65 struct enum_value {
  66   /* The next value in the enum, or null if this is the last.  */
  67   struct enum_value *next;
  68
  69   /* The name of the value as it appears in the .md file.  */
  70   char *name;
  71
  72   /* The definition of the related C value.  */
  73   struct md_constant *def;
  74 };
  75
  76 /* This structure represents an enum defined by define_enum or the like.  */
  77 struct enum_type {
  78   /* The C name of the enumeration.  */
  79   char *name;
  80
  81   /* True if this is an md-style enum (DEFINE_ENUM) rather than
  82      a C-style enum (DEFINE_C_ENUM).  */
  83   bool md_p;
  84
  85   /* The values of the enumeration.  There is always at least one.  */
  86   struct enum_value *values;
  87
  88   /* A pointer to the null terminator in VALUES.  */
  89   struct enum_value **tail_ptr;
  90
  91   /* The number of enumeration values.  */
  92   unsigned int num_values;
  93 };
  94
  95 /* Describes one instance of an overloaded_name.  */
  96 struct overloaded_instance {
  97   /* The next instance in the chain, or null if none.  */
  98   overloaded_instance *next;
  99
 100   /* The values that the overloaded_name arguments should have for this
 101      instance to be chosen.  Each value is a C token.  */
 102   vec<const char *> arg_values;
 103
 104   /* The full (non-overloaded) name of the pattern.  */
 105   const char *name;
 106
 107   /* The corresponding define_expand or define_insn.  */
 108   rtx insn;
 109 };
 110
 111 /* Describes a define_expand or define_insn whose name was preceded by '@'.
 112    Overloads are uniquely determined by their name and the types of their
 113    arguments; it's possible to have overloads with the same name but
 114    different argument types.  */
 115 struct overloaded_name {
 116   /* The next overloaded name in the chain.  */
 117   overloaded_name *next;
 118
 119   /* The overloaded name (i.e. the name with "@" character and
 120      "<...>" placeholders removed).  */
 121   const char *name;
 122
 123   /* The C types of the iterators that determine the underlying pattern,
 124      in the same order as in the pattern name.  E.g. "<mode>" in the
 125      pattern name would give a "machine_mode" argument here.  */
 126   vec<const char *> arg_types;
 127
 128   /* The first instance associated with this overloaded_name.  */
 129   overloaded_instance *first_instance;
 130
 131   /* Where to chain new overloaded_instances.  */
 132   overloaded_instance **next_instance_ptr;
 133 };
 134
 135 struct mapping;
 136
 137 /* A class for reading .md files and RTL dump files.
 138
 139    Implemented in read-md.cc.
 140
 141    This class has responsibility for reading chars from input files, and
 142    for certain common top-level directives including the "include"
 143    directive.
 144
 145    It does not handle parsing the hierarchically-nested expressions of
 146    rtl.def; for that see the rtx_reader subclass below (implemented in
 147    read-rtl.cc).  */
 148
 149 class md_reader
 150 {
 151  public:
 152   /* Associates PTR (which can be a string, etc.) with the file location
 153      specified by LOC.  */
 154   struct ptr_loc {
 155     const void *ptr;
 156     file_location loc;
 157   };
 158
 159   md_reader (bool compact);
 160   virtual ~md_reader ();
 161
 162   bool read_md_files (int, const char **, bool (*) (const char *));
 163   bool read_file (const char *filename);
 164   bool read_file_fragment (const char *filename,
 165                            int first_line,
 166                            int last_line);
 167
 168   /* A hook that handles a single .md-file directive, up to but not
 169      including the closing ')'.  It takes two arguments: the file position
 170      at which the directive started, and the name of the directive.  The next
 171      unread character is the optional space after the directive name.  */
 172   virtual void handle_unknown_directive (file_location, const char *) = 0;
 173
 174   file_location get_current_location () const;
 175
 176   bool is_compact () const { return m_compact; }
 177
 178   /* Defined in read-md.cc.  */
 179   int read_char (void);
 180   void unread_char (int ch);
 181   file_location read_name (struct md_name *name);
 182   file_location read_name_or_nil (struct md_name *);
 183   void read_escape ();
 184   char *read_quoted_string ();
 185   char *read_braced_string ();
 186   char *read_string (int star_if_braced);
 187   void read_skip_construct (int depth, file_location loc);
 188   void require_char (char expected);
 189   void require_char_ws (char expected);
 190   void require_word_ws (const char *expected);
 191   int peek_char (void);
 192
 193   void set_md_ptr_loc (const void *ptr, file_location);
 194   const struct ptr_loc *get_md_ptr_loc (const void *ptr);
 195   void copy_md_ptr_loc (const void *new_ptr, const void *old_ptr);
 196   void fprint_md_ptr_loc (FILE *outf, const void *ptr);
 197   void print_md_ptr_loc (const void *ptr);
 198
 199   struct enum_type *lookup_enum_type (const char *name);
 200   void traverse_enum_types (htab_trav callback, void *info);
 201
 202   void handle_constants ();
 203   void traverse_md_constants (htab_trav callback, void *info);
 204   void handle_enum (file_location loc, bool md_p);
 205
 206   const char *join_c_conditions (const char *cond1, const char *cond2);
 207   void fprint_c_condition (FILE *outf, const char *cond);
 208   void print_c_condition (const char *cond);
 209
 210   /* Defined in read-rtl.cc.  */
 211   const char *apply_iterator_to_string (const char *string);
 212   rtx copy_rtx_for_iterators (rtx original);
 213   void read_conditions ();
 214   void record_potential_iterator_use (struct iterator_group *group,
 215                                       file_location loc, rtx x,
 216                                       unsigned int index, const char *name);
 217   struct mapping *read_mapping (struct iterator_group *group, htab_t table);
 218   overloaded_name *handle_overloaded_name (rtx, vec<mapping *> *);
 219
 220   const char *get_top_level_filename () const { return m_toplevel_fname; }
 221   const char *get_filename () const { return m_read_md_filename; }
 222   int get_lineno () const { return m_read_md_lineno; }
 223   int get_colno () const { return m_read_md_colno; }
 224
 225   struct obstack *get_string_obstack () { return &m_string_obstack; }
 226   htab_t get_md_constants () { return m_md_constants; }
 227
 228   overloaded_name *get_overloads () const { return m_first_overload; }
 229
 230  private:
 231   /* A singly-linked list of filenames.  */
 232   struct file_name_list {
 233     struct file_name_list *next;
 234     const char *fname;
 235   };
 236
 237  private:
 238   void handle_file ();
 239   void handle_toplevel_file ();
 240   void handle_include (file_location loc);
 241   void add_include_path (const char *arg);
 242
 243   bool read_name_1 (struct md_name *name, file_location *out_loc);
 244
 245  private:
 246   /* Are we reading a compact dump?  */
 247   bool m_compact;
 248
 249   /* The name of the toplevel file that indirectly included
 250      m_read_md_file.  */
 251   const char *m_toplevel_fname;
 252
 253   /* The directory part of m_toplevel_fname
 254      NULL if m_toplevel_fname is a bare filename.  */
 255   char *m_base_dir;
 256
 257   /* The file we are reading.  */
 258   FILE *m_read_md_file;
 259
 260   /* The filename of m_read_md_file.  */
 261   const char *m_read_md_filename;
 262
 263   /* The current line number in m_read_md_file.  */
 264   int m_read_md_lineno;
 265
 266   /* The current column number in m_read_md_file.  */
 267   int m_read_md_colno;
 268
 269   /* The column number before the last newline, so that
 270      we can handle unread_char ('\n') at least once whilst
 271      retaining column information.  */
 272   int m_last_line_colno;
 273
 274   /* The first directory to search.  */
 275   file_name_list *m_first_dir_md_include;
 276
 277   /* A pointer to the null terminator of the md include chain.  */
 278   file_name_list **m_last_dir_md_include_ptr;
 279
 280   /* Obstack used for allocating MD strings.  */
 281   struct obstack m_string_obstack;
 282
 283   /* A table of ptr_locs, hashed on the PTR field.  */
 284   htab_t m_ptr_locs;
 285
 286   /* An obstack for the above.  Plain xmalloc is a bit heavyweight for a
 287      small structure like ptr_loc.  */
 288   struct obstack m_ptr_loc_obstack;
 289
 290   /* A hash table of triples (A, B, C), where each of A, B and C is a condition
 291      and A is equivalent to "B && C".  This is used to keep track of the source
 292      of conditions that are made up of separate MD strings (such as the split
 293      condition of a define_insn_and_split).  */
 294   htab_t m_joined_conditions;
 295
 296   /* An obstack for allocating joined_conditions entries.  */
 297   struct obstack m_joined_conditions_obstack;
 298
 299   /* A table of md_constant structures, hashed by name.  Null if no
 300      constant expansion should occur.  */
 301   htab_t m_md_constants;
 302
 303   /* A table of enum_type structures, hashed by name.  */
 304   htab_t m_enum_types;
 305
 306   /* If non-zero, filter the input to just this subset of lines.  */
 307   int m_first_line;
 308   int m_last_line;
 309
 310   /* The first overloaded_name.  */
 311   overloaded_name *m_first_overload;
 312
 313   /* Where to chain further overloaded_names,  */
 314   overloaded_name **m_next_overload_ptr;
 315
 316   /* A hash table of overloaded_names, keyed off their name and the types of
 317      their arguments.  */
 318   htab_t m_overloads_htab;
 319 };
 320
 321 /* Global singleton; constrast with rtx_reader_ptr below.  */
 322 extern md_reader *md_reader_ptr;
 323
 324 /* An md_reader subclass which skips unknown directives, for
 325    the gen* tools that purely use read-md.o.  */
 326
 327 class noop_reader : public md_reader
 328 {
 329  public:
 330   noop_reader () : md_reader (false) {}
 331
 332   /* A dummy implementation which skips unknown directives.  */
 333   void handle_unknown_directive (file_location, const char *) override;
 334 };
 335
 336 /* An md_reader subclass that actually handles full hierarchical
 337    rtx expressions.
 338
 339    Implemented in read-rtl.cc.  */
 340
 341 class rtx_reader : public md_reader
 342 {
 343  public:
 344   rtx_reader (bool compact);
 345   ~rtx_reader ();
 346
 347   bool read_rtx (const char *rtx_name, vec<rtx> *rtxen);
 348   rtx rtx_alloc_for_name (const char *);
 349   rtx read_rtx_code (const char *code_name);
 350   virtual rtx read_rtx_operand (rtx return_rtx, int idx);
 351   rtx read_nested_rtx ();
 352   rtx read_rtx_variadic (rtx form);
 353   char *read_until (const char *terminator_chars, bool consume_terminator);
 354
 355   virtual void handle_any_trailing_information (rtx) {}
 356   virtual rtx postprocess (rtx x) { return x; }
 357
 358   /* Hook to allow function_reader subclass to put STRINGBUF into gc-managed
 359      memory, rather than within an obstack.
 360      This base class implementation is a no-op.  */
 361   virtual const char *finalize_string (char *stringbuf) { return stringbuf; }
 362
 363  protected:
 364   /* Analogous to rtx_writer's m_in_call_function_usage.  */
 365   bool m_in_call_function_usage;
 366
 367   /* Support for "reuse_rtx" directives.  */
 368   auto_vec<rtx> m_reuse_rtx_by_id;
 369 };
 370
 371 /* Global singleton; constrast with md_reader_ptr above.  */
 372 extern rtx_reader *rtx_reader_ptr;
 373
 374 extern void (*include_callback) (const char *);
 375
 376 /* Read the next character from the MD file.  */
 377
 378 inline int
 379 read_char (void)
 380 {
 381   return md_reader_ptr->read_char ();
 382 }
 383
 384 /* Put back CH, which was the last character read from the MD file.  */
 385
 386 inline void
 387 unread_char (int ch)
 388 {
 389   md_reader_ptr->unread_char (ch);
 390 }
 391
 392 extern hashval_t leading_string_hash (const void *);
 393 extern int leading_string_eq_p (const void *, const void *);
 394 extern const char *join_c_conditions (const char *, const char *);
 395 extern void message_at (file_location, const char *, ...) ATTRIBUTE_PRINTF_2;
 396 extern void error_at (file_location, const char *, ...) ATTRIBUTE_PRINTF_2;
 397 extern void fatal_at (file_location, const char *, ...) ATTRIBUTE_PRINTF_2;
 398 extern void fatal_with_file_and_line (const char *, ...)
 399   ATTRIBUTE_PRINTF_1 ATTRIBUTE_NORETURN;
 400 extern void fatal_expected_char (int, int) ATTRIBUTE_NORETURN;
 401 extern int read_skip_spaces (void);
 402 extern int n_comma_elts (const char *);
 403 extern const char *scan_comma_elt (const char **);
 404 extern void upcase_string (char *);
 405 extern void traverse_enum_types (htab_trav, void *);
 406 extern struct enum_type *lookup_enum_type (const char *);
 407
 408 #endif /* GCC_READ_MD_H */