gcc/read-md.h

   1 /* MD reader definitions.
   2    Copyright (C) 1987-2019 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 struct file_location {
  27   file_location () {}
  28   file_location (const char *, int, int);
  29
  30   const char *filename;
  31   int lineno;
  32   int colno;
  33 };
  34
  35 inline file_location::file_location (const char *filename_in, int lineno_in, int colno_in)
  36 : filename (filename_in), lineno (lineno_in), colno (colno_in) {}
  37
  38 /* Holds one symbol or number in the .md file.  */
  39 struct md_name {
  40   /* The name as it appeared in the .md file.  Names are syntactically
  41      limited to the length of this buffer.  */
  42   char buffer[256];
  43
  44   /* The name that should actually be used by the generator programs.
  45      This is an expansion of NAME, after things like constant substitution.  */
  46   char *string;
  47 };
  48
  49 /* This structure represents a constant defined by define_constant,
  50    define_enum, or such-like.  */
  51 struct md_constant {
  52   /* The name of the constant.  */
  53   char *name;
  54
  55   /* The string to which the constants expands.  */
  56   char *value;
  57
  58   /* If the constant is associated with a enumeration, this field
  59      points to that enumeration, otherwise it is null.  */
  60   struct enum_type *parent_enum;
  61 };
  62
  63 /* This structure represents one value in an enum_type.  */
  64 struct enum_value {
  65   /* The next value in the enum, or null if this is the last.  */
  66   struct enum_value *next;
  67
  68   /* The name of the value as it appears in the .md file.  */
  69   char *name;
  70
  71   /* The definition of the related C value.  */
  72   struct md_constant *def;
  73 };
  74
  75 /* This structure represents an enum defined by define_enum or the like.  */
  76 struct enum_type {
  77   /* The C name of the enumeration.  */
  78   char *name;
  79
  80   /* True if this is an md-style enum (DEFINE_ENUM) rather than
  81      a C-style enum (DEFINE_C_ENUM).  */
  82   bool md_p;
  83
  84   /* The values of the enumeration.  There is always at least one.  */
  85   struct enum_value *values;
  86
  87   /* A pointer to the null terminator in VALUES.  */
  88   struct enum_value **tail_ptr;
  89
  90   /* The number of enumeration values.  */
  91   unsigned int num_values;
  92 };
  93
  94 /* Describes one instance of an overloaded_name.  */
  95 struct overloaded_instance {
  96   /* The next instance in the chain, or null if none.  */
  97   overloaded_instance *next;
  98
  99   /* The values that the overloaded_name arguments should have for this
 100      instance to be chosen.  Each value is a C token.  */
 101   vec<const char *> arg_values;
 102
 103   /* The full (non-overloaded) name of the pattern.  */
 104   const char *name;
 105
 106   /* The corresponding define_expand or define_insn.  */
 107   rtx insn;
 108 };
 109
 110 /* Describes a define_expand or define_insn whose name was preceded by '@'.
 111    Overloads are uniquely determined by their name and the types of their
 112    arguments; it's possible to have overloads with the same name but
 113    different argument types.  */
 114 struct overloaded_name {
 115   /* The next overloaded name in the chain.  */
 116   overloaded_name *next;
 117
 118   /* The overloaded name (i.e. the name with "@" character and
 119      "<...>" placeholders removed).  */
 120   const char *name;
 121
 122   /* The C types of the iterators that determine the underlying pattern,
 123      in the same order as in the pattern name.  E.g. "<mode>" in the
 124      pattern name would give a "machine_mode" argument here.  */
 125   vec<const char *> arg_types;
 126
 127   /* The first instance associated with this overloaded_name.  */
 128   overloaded_instance *first_instance;
 129
 130   /* Where to chain new overloaded_instances.  */
 131   overloaded_instance **next_instance_ptr;
 132 };
 133
 134 struct mapping;
 135
 136 /* A class for reading .md files and RTL dump files.
 137
 138    Implemented in read-md.c.
 139
 140    This class has responsibility for reading chars from input files, and
 141    for certain common top-level directives including the "include"
 142    directive.
 143
 144    It does not handle parsing the hierarchically-nested expressions of
 145    rtl.def; for that see the rtx_reader subclass below (implemented in
 146    read-rtl.c).  */
 147
 148 class md_reader
 149 {
 150  public:
 151   md_reader (bool compact);
 152   virtual ~md_reader ();
 153
 154   bool read_md_files (int, const char **, bool (*) (const char *));
 155   bool read_file (const char *filename);
 156   bool read_file_fragment (const char *filename,
 157                            int first_line,
 158                            int last_line);
 159
 160   /* A hook that handles a single .md-file directive, up to but not
 161      including the closing ')'.  It takes two arguments: the file position
 162      at which the directive started, and the name of the directive.  The next
 163      unread character is the optional space after the directive name.  */
 164   virtual void handle_unknown_directive (file_location, const char *) = 0;
 165
 166   file_location get_current_location () const;
 167
 168   bool is_compact () const { return m_compact; }
 169
 170   /* Defined in read-md.c.  */
 171   int read_char (void);
 172   void unread_char (int ch);
 173   file_location read_name (struct md_name *name);
 174   file_location read_name_or_nil (struct md_name *);
 175   void read_escape ();
 176   char *read_quoted_string ();
 177   char *read_braced_string ();
 178   char *read_string (int star_if_braced);
 179   void read_skip_construct (int depth, file_location loc);
 180   void require_char (char expected);
 181   void require_char_ws (char expected);
 182   void require_word_ws (const char *expected);
 183   int peek_char (void);
 184
 185   void set_md_ptr_loc (const void *ptr, const char *filename, int lineno);
 186   const struct ptr_loc *get_md_ptr_loc (const void *ptr);
 187   void copy_md_ptr_loc (const void *new_ptr, const void *old_ptr);
 188   void fprint_md_ptr_loc (FILE *outf, const void *ptr);
 189   void print_md_ptr_loc (const void *ptr);
 190
 191   struct enum_type *lookup_enum_type (const char *name);
 192   void traverse_enum_types (htab_trav callback, void *info);
 193
 194   void handle_constants ();
 195   void traverse_md_constants (htab_trav callback, void *info);
 196   void handle_enum (file_location loc, bool md_p);
 197
 198   const char *join_c_conditions (const char *cond1, const char *cond2);
 199   void fprint_c_condition (FILE *outf, const char *cond);
 200   void print_c_condition (const char *cond);
 201
 202   /* Defined in read-rtl.c.  */
 203   const char *apply_iterator_to_string (const char *string);
 204   rtx copy_rtx_for_iterators (rtx original);
 205   void read_conditions ();
 206   void record_potential_iterator_use (struct iterator_group *group,
 207                                       rtx x, unsigned int index,
 208                                       const char *name);
 209   struct mapping *read_mapping (struct iterator_group *group, htab_t table);
 210   overloaded_name *handle_overloaded_name (rtx, vec<mapping *> *);
 211
 212   const char *get_top_level_filename () const { return m_toplevel_fname; }
 213   const char *get_filename () const { return m_read_md_filename; }
 214   int get_lineno () const { return m_read_md_lineno; }
 215   int get_colno () const { return m_read_md_colno; }
 216
 217   struct obstack *get_string_obstack () { return &m_string_obstack; }
 218   htab_t get_md_constants () { return m_md_constants; }
 219
 220   overloaded_name *get_overloads () const { return m_first_overload; }
 221
 222  private:
 223   /* A singly-linked list of filenames.  */
 224   struct file_name_list {
 225     struct file_name_list *next;
 226     const char *fname;
 227   };
 228
 229  private:
 230   void handle_file ();
 231   void handle_toplevel_file ();
 232   void handle_include (file_location loc);
 233   void add_include_path (const char *arg);
 234
 235   bool read_name_1 (struct md_name *name, file_location *out_loc);
 236
 237  private:
 238   /* Are we reading a compact dump?  */
 239   bool m_compact;
 240
 241   /* The name of the toplevel file that indirectly included
 242      m_read_md_file.  */
 243   const char *m_toplevel_fname;
 244
 245   /* The directory part of m_toplevel_fname
 246      NULL if m_toplevel_fname is a bare filename.  */
 247   char *m_base_dir;
 248
 249   /* The file we are reading.  */
 250   FILE *m_read_md_file;
 251
 252   /* The filename of m_read_md_file.  */
 253   const char *m_read_md_filename;
 254
 255   /* The current line number in m_read_md_file.  */
 256   int m_read_md_lineno;
 257
 258   /* The current column number in m_read_md_file.  */
 259   int m_read_md_colno;
 260
 261   /* The column number before the last newline, so that
 262      we can handle unread_char ('\n') at least once whilst
 263      retaining column information.  */
 264   int m_last_line_colno;
 265
 266   /* The first directory to search.  */
 267   file_name_list *m_first_dir_md_include;
 268
 269   /* A pointer to the null terminator of the md include chain.  */
 270   file_name_list **m_last_dir_md_include_ptr;
 271
 272   /* Obstack used for allocating MD strings.  */
 273   struct obstack m_string_obstack;
 274
 275   /* A table of ptr_locs, hashed on the PTR field.  */
 276   htab_t m_ptr_locs;
 277
 278   /* An obstack for the above.  Plain xmalloc is a bit heavyweight for a
 279      small structure like ptr_loc.  */
 280   struct obstack m_ptr_loc_obstack;
 281
 282   /* A hash table of triples (A, B, C), where each of A, B and C is a condition
 283      and A is equivalent to "B && C".  This is used to keep track of the source
 284      of conditions that are made up of separate MD strings (such as the split
 285      condition of a define_insn_and_split).  */
 286   htab_t m_joined_conditions;
 287
 288   /* An obstack for allocating joined_conditions entries.  */
 289   struct obstack m_joined_conditions_obstack;
 290
 291   /* A table of md_constant structures, hashed by name.  Null if no
 292      constant expansion should occur.  */
 293   htab_t m_md_constants;
 294
 295   /* A table of enum_type structures, hashed by name.  */
 296   htab_t m_enum_types;
 297
 298   /* If non-zero, filter the input to just this subset of lines.  */
 299   int m_first_line;
 300   int m_last_line;
 301
 302   /* The first overloaded_name.  */
 303   overloaded_name *m_first_overload;
 304
 305   /* Where to chain further overloaded_names,  */
 306   overloaded_name **m_next_overload_ptr;
 307
 308   /* A hash table of overloaded_names, keyed off their name and the types of
 309      their arguments.  */
 310   htab_t m_overloads_htab;
 311 };
 312
 313 /* Global singleton; constrast with rtx_reader_ptr below.  */
 314 extern md_reader *md_reader_ptr;
 315
 316 /* An md_reader subclass which skips unknown directives, for
 317    the gen* tools that purely use read-md.o.  */
 318
 319 class noop_reader : public md_reader
 320 {
 321  public:
 322   noop_reader () : md_reader (false) {}
 323
 324   /* A dummy implementation which skips unknown directives.  */
 325   void handle_unknown_directive (file_location, const char *);
 326 };
 327
 328 /* An md_reader subclass that actually handles full hierarchical
 329    rtx expressions.
 330
 331    Implemented in read-rtl.c.  */
 332
 333 class rtx_reader : public md_reader
 334 {
 335  public:
 336   rtx_reader (bool compact);
 337   ~rtx_reader ();
 338
 339   bool read_rtx (const char *rtx_name, vec<rtx> *rtxen);
 340   rtx read_rtx_code (const char *code_name);
 341   virtual rtx read_rtx_operand (rtx return_rtx, int idx);
 342   rtx read_nested_rtx ();
 343   rtx read_rtx_variadic (rtx form);
 344   char *read_until (const char *terminator_chars, bool consume_terminator);
 345
 346   virtual void handle_any_trailing_information (rtx) {}
 347   virtual rtx postprocess (rtx x) { return x; }
 348
 349   /* Hook to allow function_reader subclass to put STRINGBUF into gc-managed
 350      memory, rather than within an obstack.
 351      This base class implementation is a no-op.  */
 352   virtual const char *finalize_string (char *stringbuf) { return stringbuf; }
 353
 354  protected:
 355   /* Analogous to rtx_writer's m_in_call_function_usage.  */
 356   bool m_in_call_function_usage;
 357
 358   /* Support for "reuse_rtx" directives.  */
 359   auto_vec<rtx> m_reuse_rtx_by_id;
 360 };
 361
 362 /* Global singleton; constrast with md_reader_ptr above.  */
 363 extern rtx_reader *rtx_reader_ptr;
 364
 365 extern void (*include_callback) (const char *);
 366
 367 /* Read the next character from the MD file.  */
 368
 369 static inline int
 370 read_char (void)
 371 {
 372   return md_reader_ptr->read_char ();
 373 }
 374
 375 /* Put back CH, which was the last character read from the MD file.  */
 376
 377 static inline void
 378 unread_char (int ch)
 379 {
 380   md_reader_ptr->unread_char (ch);
 381 }
 382
 383 extern hashval_t leading_string_hash (const void *);
 384 extern int leading_string_eq_p (const void *, const void *);
 385 extern const char *join_c_conditions (const char *, const char *);
 386 extern void message_at (file_location, const char *, ...) ATTRIBUTE_PRINTF_2;
 387 extern void error_at (file_location, const char *, ...) ATTRIBUTE_PRINTF_2;
 388 extern void fatal_at (file_location, const char *, ...) ATTRIBUTE_PRINTF_2;
 389 extern void fatal_with_file_and_line (const char *, ...)
 390   ATTRIBUTE_PRINTF_1 ATTRIBUTE_NORETURN;
 391 extern void fatal_expected_char (int, int) ATTRIBUTE_NORETURN;
 392 extern int read_skip_spaces (void);
 393 extern int n_comma_elts (const char *);
 394 extern const char *scan_comma_elt (const char **);
 395 extern void upcase_string (char *);
 396 extern void traverse_enum_types (htab_trav, void *);
 397 extern struct enum_type *lookup_enum_type (const char *);
 398
 399 #endif /* GCC_READ_MD_H */