gcc/genattr.c

   1 /* Generate attribute information (insn-attr.h) from machine description.
   2    Copyright (C) 1991, 1994, 1996, 1998, 1999, 2000, 2003, 2004, 2007, 2008,
   3    2010  Free Software Foundation, Inc.
   4    Contributed by Richard Kenner (kenner@vlsi1.ultra.nyu.edu)
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 3, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22
  23 #include "bconfig.h"
  24 #include "system.h"
  25 #include "coretypes.h"
  26 #include "tm.h"
  27 #include "rtl.h"
  28 #include "errors.h"
  29 #include "read-md.h"
  30 #include "gensupport.h"
  31
  32
  33 static void write_upcase (const char *);
  34 static void gen_attr (rtx);
  35
  36 static void
  37 write_upcase (const char *str)
  38 {
  39   for (; *str; str++)
  40     putchar (TOUPPER(*str));
  41 }
  42
  43 static VEC (rtx, heap) *const_attrs, *reservations;
  44
  45
  46 static void
  47 gen_attr (rtx attr)
  48 {
  49   const char *p, *tag;
  50   int is_const = GET_CODE (XEXP (attr, 2)) == CONST;
  51
  52   if (is_const)
  53     VEC_safe_push (rtx, heap, const_attrs, attr);
  54
  55   printf ("#define HAVE_ATTR_%s\n", XSTR (attr, 0));
  56
  57   /* If numeric attribute, don't need to write an enum.  */
  58   if (GET_CODE (attr) == DEFINE_ENUM_ATTR)
  59     printf ("extern enum %s get_attr_%s (%s);\n\n",
  60             XSTR (attr, 1), XSTR (attr, 0), (is_const ? "void" : "rtx"));
  61   else
  62     {
  63       p = XSTR (attr, 1);
  64       if (*p == '\0')
  65         printf ("extern int get_attr_%s (%s);\n", XSTR (attr, 0),
  66                 (is_const ? "void" : "rtx"));
  67       else
  68         {
  69           printf ("enum attr_%s {", XSTR (attr, 0));
  70
  71           while ((tag = scan_comma_elt (&p)) != 0)
  72             {
  73               write_upcase (XSTR (attr, 0));
  74               putchar ('_');
  75               while (tag != p)
  76                 putchar (TOUPPER (*tag++));
  77               if (*p == ',')
  78                 fputs (", ", stdout);
  79             }
  80           fputs ("};\n", stdout);
  81
  82           printf ("extern enum attr_%s get_attr_%s (%s);\n\n",
  83                   XSTR (attr, 0), XSTR (attr, 0), (is_const ? "void" : "rtx"));
  84         }
  85     }
  86
  87   /* If `length' attribute, write additional function definitions and define
  88      variables used by `insn_current_length'.  */
  89   if (! strcmp (XSTR (attr, 0), "length"))
  90     {
  91       puts ("\
  92 extern void shorten_branches (rtx);\n\
  93 extern int insn_default_length (rtx);\n\
  94 extern int insn_min_length (rtx);\n\
  95 extern int insn_variable_length_p (rtx);\n\
  96 extern int insn_current_length (rtx);\n\n\
  97 #include \"insn-addr.h\"\n");
  98     }
  99 }
 100
 101 /* Check that attribute NAME is used in define_insn_reservation condition
 102    EXP.  Return true if it is.  */
 103 static bool
 104 check_tune_attr (const char *name, rtx exp)
 105 {
 106   switch (GET_CODE (exp))
 107     {
 108     case AND:
 109       if (check_tune_attr (name, XEXP (exp, 0)))
 110         return true;
 111       return check_tune_attr (name, XEXP (exp, 1));
 112
 113     case IOR:
 114       return (check_tune_attr (name, XEXP (exp, 0))
 115               && check_tune_attr (name, XEXP (exp, 1)));
 116
 117     case EQ_ATTR:
 118       return strcmp (XSTR (exp, 0), name) == 0;
 119
 120     default:
 121       return false;
 122     }
 123 }
 124
 125 /* Try to find a const attribute (usually cpu or tune) that is used
 126    in all define_insn_reservation conditions.  */
 127 static bool
 128 find_tune_attr (rtx exp)
 129 {
 130   unsigned int i;
 131   rtx attr;
 132
 133   switch (GET_CODE (exp))
 134     {
 135     case AND:
 136     case IOR:
 137       if (find_tune_attr (XEXP (exp, 0)))
 138         return true;
 139       return find_tune_attr (XEXP (exp, 1));
 140
 141     case EQ_ATTR:
 142       if (strcmp (XSTR (exp, 0), "alternative") == 0)
 143         return false;
 144
 145       FOR_EACH_VEC_ELT (rtx, const_attrs, i, attr)
 146         if (strcmp (XSTR (attr, 0), XSTR (exp, 0)) == 0)
 147           {
 148             unsigned int j;
 149             rtx resv;
 150
 151             FOR_EACH_VEC_ELT (rtx, reservations, j, resv)
 152               if (! check_tune_attr (XSTR (attr, 0), XEXP (resv, 2)))
 153                 return false;
 154             return true;
 155           }
 156       return false;
 157
 158     default:
 159       return false;
 160     }
 161 }
 162
 163 int
 164 main (int argc, char **argv)
 165 {
 166   rtx desc;
 167   int have_delay = 0;
 168   int have_annul_true = 0;
 169   int have_annul_false = 0;
 170   int num_insn_reservations = 0;
 171   int i;
 172
 173   progname = "genattr";
 174
 175   if (!init_rtx_reader_args (argc, argv))
 176     return (FATAL_EXIT_CODE);
 177
 178   puts ("/* Generated automatically by the program `genattr'");
 179   puts ("   from the machine description file `md'.  */\n");
 180   puts ("#ifndef GCC_INSN_ATTR_H");
 181   puts ("#define GCC_INSN_ATTR_H\n");
 182
 183   /* For compatibility, define the attribute `alternative', which is just
 184      a reference to the variable `which_alternative'.  */
 185
 186   puts ("#define HAVE_ATTR_alternative");
 187   puts ("#define get_attr_alternative(insn) which_alternative");
 188
 189   /* Read the machine description.  */
 190
 191   while (1)
 192     {
 193       int line_no, insn_code_number;
 194
 195       desc = read_md_rtx (&line_no, &insn_code_number);
 196       if (desc == NULL)
 197         break;
 198
 199       if (GET_CODE (desc) == DEFINE_ATTR
 200           || GET_CODE (desc) == DEFINE_ENUM_ATTR)
 201         gen_attr (desc);
 202
 203       else if (GET_CODE (desc) == DEFINE_DELAY)
 204         {
 205           if (! have_delay)
 206             {
 207               printf ("#define DELAY_SLOTS\n");
 208               printf ("extern int num_delay_slots (rtx);\n");
 209               printf ("extern int eligible_for_delay (rtx, int, rtx, int);\n\n");
 210               printf ("extern int const_num_delay_slots (rtx);\n\n");
 211               have_delay = 1;
 212             }
 213
 214           for (i = 0; i < XVECLEN (desc, 1); i += 3)
 215             {
 216               if (XVECEXP (desc, 1, i + 1) && ! have_annul_true)
 217                 {
 218                   printf ("#define ANNUL_IFTRUE_SLOTS\n");
 219                   printf ("extern int eligible_for_annul_true (rtx, int, rtx, int);\n");
 220                   have_annul_true = 1;
 221                 }
 222
 223               if (XVECEXP (desc, 1, i + 2) && ! have_annul_false)
 224                 {
 225                   printf ("#define ANNUL_IFFALSE_SLOTS\n");
 226                   printf ("extern int eligible_for_annul_false (rtx, int, rtx, int);\n");
 227                   have_annul_false = 1;
 228                 }
 229             }
 230         }
 231
 232       else if (GET_CODE (desc) == DEFINE_INSN_RESERVATION)
 233         {
 234           num_insn_reservations++;
 235           VEC_safe_push (rtx, heap, reservations, desc);
 236         }
 237     }
 238
 239   if (num_insn_reservations > 0)
 240     {
 241       bool has_tune_attr
 242         = find_tune_attr (XEXP (VEC_index (rtx, reservations, 0), 2));
 243       /* Output interface for pipeline hazards recognition based on
 244          DFA (deterministic finite state automata.  */
 245       printf ("\n#define INSN_SCHEDULING\n");
 246       printf ("\n/* DFA based pipeline interface.  */");
 247       printf ("\n#ifndef AUTOMATON_ALTS\n");
 248       printf ("#define AUTOMATON_ALTS 0\n");
 249       printf ("#endif\n\n");
 250       printf ("\n#ifndef AUTOMATON_STATE_ALTS\n");
 251       printf ("#define AUTOMATON_STATE_ALTS 0\n");
 252       printf ("#endif\n\n");
 253       printf ("#ifndef CPU_UNITS_QUERY\n");
 254       printf ("#define CPU_UNITS_QUERY 0\n");
 255       printf ("#endif\n\n");
 256       /* Interface itself: */
 257       if (has_tune_attr)
 258         {
 259           printf ("/* Initialize fn pointers for internal_dfa_insn_code\n");
 260           printf ("   and insn_default_latency.  */\n");
 261           printf ("extern void init_sched_attrs (void);\n\n");
 262           printf ("/* Internal insn code number used by automata.  */\n");
 263           printf ("extern int (*internal_dfa_insn_code) (rtx);\n\n");
 264           printf ("/* Insn latency time defined in define_insn_reservation. */\n");
 265           printf ("extern int (*insn_default_latency) (rtx);\n\n");
 266         }
 267       else
 268         {
 269           printf ("#define init_sched_attrs() do { } while (0)\n\n");
 270           printf ("/* Internal insn code number used by automata.  */\n");
 271           printf ("extern int internal_dfa_insn_code (rtx);\n\n");
 272           printf ("/* Insn latency time defined in define_insn_reservation. */\n");
 273           printf ("extern int insn_default_latency (rtx);\n\n");
 274         }
 275       printf ("/* Return nonzero if there is a bypass for given insn\n");
 276       printf ("   which is a data producer.  */\n");
 277       printf ("extern int bypass_p (rtx);\n\n");
 278       printf ("/* Insn latency time on data consumed by the 2nd insn.\n");
 279       printf ("   Use the function if bypass_p returns nonzero for\n");
 280       printf ("   the 1st insn. */\n");
 281       printf ("extern int insn_latency (rtx, rtx);\n\n");
 282       printf ("/* Maximal insn latency time possible of all bypasses for this insn.\n");
 283       printf ("   Use the function if bypass_p returns nonzero for\n");
 284       printf ("   the 1st insn. */\n");
 285       printf ("extern int maximal_insn_latency (rtx);\n\n");
 286       printf ("\n#if AUTOMATON_ALTS\n");
 287       printf ("/* The following function returns number of alternative\n");
 288       printf ("   reservations of given insn.  It may be used for better\n");
 289       printf ("   insns scheduling heuristics. */\n");
 290       printf ("extern int insn_alts (rtx);\n\n");
 291       printf ("#endif\n\n");
 292       printf ("/* Maximal possible number of insns waiting results being\n");
 293       printf ("   produced by insns whose execution is not finished. */\n");
 294       printf ("extern const int max_insn_queue_index;\n\n");
 295       printf ("/* Pointer to data describing current state of DFA.  */\n");
 296       printf ("typedef void *state_t;\n\n");
 297       printf ("/* Size of the data in bytes.  */\n");
 298       printf ("extern int state_size (void);\n\n");
 299       printf ("/* Initiate given DFA state, i.e. Set up the state\n");
 300       printf ("   as all functional units were not reserved.  */\n");
 301       printf ("extern void state_reset (state_t);\n");
 302       printf ("/* The following function returns negative value if given\n");
 303       printf ("   insn can be issued in processor state described by given\n");
 304       printf ("   DFA state.  In this case, the DFA state is changed to\n");
 305       printf ("   reflect the current and future reservations by given\n");
 306       printf ("   insn.  Otherwise the function returns minimal time\n");
 307       printf ("   delay to issue the insn.  This delay may be zero\n");
 308       printf ("   for superscalar or VLIW processors.  If the second\n");
 309       printf ("   parameter is NULL the function changes given DFA state\n");
 310       printf ("   as new processor cycle started.  */\n");
 311       printf ("extern int state_transition (state_t, rtx);\n");
 312       printf ("\n#if AUTOMATON_STATE_ALTS\n");
 313       printf ("/* The following function returns number of possible\n");
 314       printf ("   alternative reservations of given insn in given\n");
 315       printf ("   DFA state.  It may be used for better insns scheduling\n");
 316       printf ("   heuristics.  By default the function is defined if\n");
 317       printf ("   macro AUTOMATON_STATE_ALTS is defined because its\n");
 318       printf ("   implementation may require much memory.  */\n");
 319       printf ("extern int state_alts (state_t, rtx);\n");
 320       printf ("#endif\n\n");
 321       printf ("extern int min_issue_delay (state_t, rtx);\n");
 322       printf ("/* The following function returns nonzero if no one insn\n");
 323       printf ("   can be issued in current DFA state. */\n");
 324       printf ("extern int state_dead_lock_p (state_t);\n");
 325       printf ("/* The function returns minimal delay of issue of the 2nd\n");
 326       printf ("   insn after issuing the 1st insn in given DFA state.\n");
 327       printf ("   The 1st insn should be issued in given state (i.e.\n");
 328       printf ("    state_transition should return negative value for\n");
 329       printf ("    the insn and the state).  Data dependencies between\n");
 330       printf ("    the insns are ignored by the function.  */\n");
 331       printf
 332         ("extern int min_insn_conflict_delay (state_t, rtx, rtx);\n");
 333       printf ("/* The following function outputs reservations for given\n");
 334       printf ("   insn as they are described in the corresponding\n");
 335       printf ("   define_insn_reservation.  */\n");
 336       printf ("extern void print_reservation (FILE *, rtx);\n");
 337       printf ("\n#if CPU_UNITS_QUERY\n");
 338       printf ("/* The following function returns code of functional unit\n");
 339       printf ("   with given name (see define_cpu_unit). */\n");
 340       printf ("extern int get_cpu_unit_code (const char *);\n");
 341       printf ("/* The following function returns nonzero if functional\n");
 342       printf ("   unit with given code is currently reserved in given\n");
 343       printf ("   DFA state.  */\n");
 344       printf ("extern int cpu_unit_reservation_p (state_t, int);\n");
 345       printf ("#endif\n\n");
 346       printf ("/* The following function returns true if insn\n");
 347       printf ("   has a dfa reservation.  */\n");
 348       printf ("extern bool insn_has_dfa_reservation_p (rtx);\n\n");
 349       printf ("/* Clean insn code cache.  It should be called if there\n");
 350       printf ("   is a chance that condition value in a\n");
 351       printf ("   define_insn_reservation will be changed after\n");
 352       printf ("   last call of dfa_start.  */\n");
 353       printf ("extern void dfa_clean_insn_cache (void);\n\n");
 354       printf ("extern void dfa_clear_single_insn_cache (rtx);\n\n");
 355       printf ("/* Initiate and finish work with DFA.  They should be\n");
 356       printf ("   called as the first and the last interface\n");
 357       printf ("   functions.  */\n");
 358       printf ("extern void dfa_start (void);\n");
 359       printf ("extern void dfa_finish (void);\n");
 360     }
 361   else
 362     {
 363       /* Otherwise we do no scheduling, but we need these typedefs
 364          in order to avoid uglifying other code with more ifdefs.  */
 365       printf ("typedef void *state_t;\n\n");
 366     }
 367
 368   /* Output flag masks for use by reorg.
 369
 370      Flags are used to hold branch direction and prediction information
 371      for use by eligible_for_...  */
 372   printf("\n#define ATTR_FLAG_forward\t0x1\n");
 373   printf("#define ATTR_FLAG_backward\t0x2\n");
 374   printf("#define ATTR_FLAG_likely\t0x4\n");
 375   printf("#define ATTR_FLAG_very_likely\t0x8\n");
 376   printf("#define ATTR_FLAG_unlikely\t0x10\n");
 377   printf("#define ATTR_FLAG_very_unlikely\t0x20\n");
 378
 379   puts("\n#endif /* GCC_INSN_ATTR_H */");
 380
 381   if (ferror (stdout) || fflush (stdout) || fclose (stdout))
 382     return FATAL_EXIT_CODE;
 383
 384   return SUCCESS_EXIT_CODE;
 385 }