gcc/basic-block.h

   1 /* Define control and data flow tables, and regsets.
   2    Copyright (C) 1987, 1997, 1998, 1999 Free Software Foundation, Inc.
   3
   4 This file is part of GNU CC.
   5
   6 GNU CC 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 2, or (at your option)
   9 any later version.
  10
  11 GNU CC 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 GNU CC; see the file COPYING.  If not, write to
  18 the Free Software Foundation, 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21
  22 #include "bitmap.h"
  23 #include "sbitmap.h"
  24 #include "varray.h"
  25
  26 typedef bitmap regset;          /* Head of register set linked list.  */
  27
  28 /* Clear a register set by freeing up the linked list.  */
  29 #define CLEAR_REG_SET(HEAD) bitmap_clear (HEAD)
  30
  31 /* Copy a register set to another register set.  */
  32 #define COPY_REG_SET(TO, FROM) bitmap_copy (TO, FROM)
  33
  34 /* `and' a register set with a second register set.  */
  35 #define AND_REG_SET(TO, FROM) bitmap_operation (TO, TO, FROM, BITMAP_AND)
  36
  37 /* `and' the complement of a register set with a register set.  */
  38 #define AND_COMPL_REG_SET(TO, FROM) \
  39   bitmap_operation (TO, TO, FROM, BITMAP_AND_COMPL)
  40
  41 /* Inclusive or a register set with a second register set.  */
  42 #define IOR_REG_SET(TO, FROM) bitmap_operation (TO, TO, FROM, BITMAP_IOR)
  43
  44 /* Or into TO the register set FROM1 `and'ed with the complement of FROM2.  */
  45 #define IOR_AND_COMPL_REG_SET(TO, FROM1, FROM2) \
  46   bitmap_ior_and_compl (TO, FROM1, FROM2)
  47
  48 /* Clear a single register in a register set.  */
  49 #define CLEAR_REGNO_REG_SET(HEAD, REG) bitmap_clear_bit (HEAD, REG)
  50
  51 /* Set a single register in a register set.  */
  52 #define SET_REGNO_REG_SET(HEAD, REG) bitmap_set_bit (HEAD, REG)
  53
  54 /* Return true if a register is set in a register set.  */
  55 #define REGNO_REG_SET_P(TO, REG) bitmap_bit_p (TO, REG)
  56
  57 /* Copy the hard registers in a register set to the hard register set.  */
  58 #define REG_SET_TO_HARD_REG_SET(TO, FROM)                               \
  59 do {                                                                    \
  60   int i_;                                                               \
  61   CLEAR_HARD_REG_SET (TO);                                              \
  62   for (i_ = 0; i_ < FIRST_PSEUDO_REGISTER; i_++)                        \
  63     if (REGNO_REG_SET_P (FROM, i_))                                     \
  64       SET_HARD_REG_BIT (TO, i_);                                        \
  65 } while (0)
  66
  67 /* Loop over all registers in REGSET, starting with MIN, setting REGNUM to the
  68    register number and executing CODE for all registers that are set. */
  69 #define EXECUTE_IF_SET_IN_REG_SET(REGSET, MIN, REGNUM, CODE)            \
  70   EXECUTE_IF_SET_IN_BITMAP (REGSET, MIN, REGNUM, CODE)
  71
  72 /* Loop over all registers in REGSET1 and REGSET2, starting with MIN, setting
  73    REGNUM to the register number and executing CODE for all registers that are
  74    set in the first regset and not set in the second. */
  75 #define EXECUTE_IF_AND_COMPL_IN_REG_SET(REGSET1, REGSET2, MIN, REGNUM, CODE) \
  76   EXECUTE_IF_AND_COMPL_IN_BITMAP (REGSET1, REGSET2, MIN, REGNUM, CODE)
  77
  78 /* Loop over all registers in REGSET1 and REGSET2, starting with MIN, setting
  79    REGNUM to the register number and executing CODE for all registers that are
  80    set in both regsets. */
  81 #define EXECUTE_IF_AND_IN_REG_SET(REGSET1, REGSET2, MIN, REGNUM, CODE) \
  82   EXECUTE_IF_AND_IN_BITMAP (REGSET1, REGSET2, MIN, REGNUM, CODE)
  83
  84 /* Allocate a register set with oballoc.  */
  85 #define OBSTACK_ALLOC_REG_SET(OBSTACK) BITMAP_OBSTACK_ALLOC (OBSTACK)
  86
  87 /* Allocate a register set with alloca.  */
  88 #define ALLOCA_REG_SET() BITMAP_ALLOCA ()
  89
  90 /* Do any cleanup needed on a regset when it is no longer used.  */
  91 #define FREE_REG_SET(REGSET) BITMAP_FREE(REGSET)
  92
  93 /* Do any one-time initializations needed for regsets.  */
  94 #define INIT_ONCE_REG_SET() BITMAP_INIT_ONCE ()
  95
  96 /* Grow any tables needed when the number of registers is calculated
  97    or extended.  For the linked list allocation, nothing needs to
  98    be done, other than zero the statistics on the first allocation.  */
  99 #define MAX_REGNO_REG_SET(NUM_REGS, NEW_P, RENUMBER_P)
 100
 101 /* Control flow edge information.  */
 102 typedef struct edge_def {
 103   /* Links through the predecessor and successor lists.  */
 104   struct edge_def *pred_next, *succ_next;
 105
 106   /* The two blocks at the ends of the edge.  */
 107   struct basic_block_def *src, *dest;
 108
 109   /* Instructions queued on the edge.  */
 110   rtx insns;
 111
 112   /* Auxiliary info specific to a pass.  */
 113   void *aux;
 114
 115   int flags;                    /* see EDGE_* below  */
 116   int probability;              /* biased by REG_BR_PROB_BASE */
 117 } *edge;
 118
 119 #define EDGE_FALLTHRU           1
 120 #define EDGE_CRITICAL           2
 121 #define EDGE_ABNORMAL           4
 122 #define EDGE_ABNORMAL_CALL      8
 123 #define EDGE_EH                 16
 124 #define EDGE_FAKE               32
 125
 126
 127 /* Basic block information indexed by block number.  */
 128 typedef struct basic_block_def {
 129   /* The first and last insns of the block.  */
 130   rtx head, end;
 131
 132   /* The edges into and out of the block.  */
 133   edge pred, succ;
 134
 135   /* Liveness info.  */
 136   regset local_set;
 137   regset global_live_at_start;
 138   regset global_live_at_end;
 139
 140   /* Auxiliary info specific to a pass.  */
 141   void *aux;
 142
 143   /* The index of this block.  */
 144   int index;
 145   /* The loop depth of this block plus one.  */
 146   int loop_depth;
 147
 148   /* The active eh region before head and after end.  */
 149   int eh_beg, eh_end;
 150 } *basic_block;
 151
 152 /* Number of basic blocks in the current function.  */
 153
 154 extern int n_basic_blocks;
 155
 156 /* Index by basic block number, get basic block struct info.  */
 157
 158 extern varray_type basic_block_info;
 159
 160 #define BASIC_BLOCK(N)  (VARRAY_BB (basic_block_info, (N)))
 161
 162 /* What registers are live at the setjmp call.  */
 163
 164 extern regset regs_live_at_setjmp;
 165
 166 /* Indexed by n, gives number of basic block that  (REG n) is used in.
 167    If the value is REG_BLOCK_GLOBAL (-2),
 168    it means (REG n) is used in more than one basic block.
 169    REG_BLOCK_UNKNOWN (-1) means it hasn't been seen yet so we don't know.
 170    This information remains valid for the rest of the compilation
 171    of the current function; it is used to control register allocation.  */
 172
 173 #define REG_BLOCK_UNKNOWN -1
 174 #define REG_BLOCK_GLOBAL -2
 175
 176 #define REG_BASIC_BLOCK(N) (VARRAY_REG (reg_n_info, N)->basic_block)
 177
 178 /* List of integers.
 179    These are used for storing things like predecessors, etc.
 180
 181    This scheme isn't very space efficient, especially on 64 bit machines.
 182    The interface is designed so that the implementation can be replaced with
 183    something more efficient if desirable.  */
 184
 185 typedef struct int_list {
 186   struct int_list *next;
 187   int val;
 188 } int_list;
 189
 190 typedef int_list *int_list_ptr;
 191
 192 /* Integer list elements are allocated in blocks to reduce the frequency
 193    of calls to malloc and to reduce the associated space overhead.  */
 194
 195 typedef struct int_list_block {
 196   struct int_list_block *next;
 197   int nodes_left;
 198 #define INT_LIST_NODES_IN_BLK 500
 199   struct int_list nodes[INT_LIST_NODES_IN_BLK];
 200 } int_list_block;
 201
 202 /* Given a pointer to the list, return pointer to first element.  */
 203 #define INT_LIST_FIRST(il) (il)
 204
 205 /* Given a pointer to a list element, return pointer to next element.  */
 206 #define INT_LIST_NEXT(p) ((p)->next)
 207
 208 /* Return non-zero if P points to the end of the list.  */
 209 #define INT_LIST_END(p) ((p) == NULL)
 210
 211 /* Return element pointed to by P.  */
 212 #define INT_LIST_VAL(p) ((p)->val)
 213
 214 #define INT_LIST_SET_VAL(p, new_val) ((p)->val = (new_val))
 215
 216 extern void free_int_list               PROTO ((int_list_block **));
 217 \f
 218 /* Stuff for recording basic block info.  */
 219
 220 #define BLOCK_HEAD(B)      (BASIC_BLOCK (B)->head)
 221 #define BLOCK_END(B)       (BASIC_BLOCK (B)->end)
 222
 223 /* Special block numbers [markers] for entry and exit.  */
 224 #define ENTRY_BLOCK (-1)
 225 #define EXIT_BLOCK (-2)
 226
 227 /* Similarly, block pointers for the edge list.  */
 228 extern struct basic_block_def entry_exit_blocks[2];
 229 #define ENTRY_BLOCK_PTR (&entry_exit_blocks[0])
 230 #define EXIT_BLOCK_PTR  (&entry_exit_blocks[1])
 231
 232 /* from flow.c */
 233 extern void free_regset_vector          PROTO ((regset *, int nelts));
 234
 235 extern varray_type basic_block_for_insn;
 236 #define BLOCK_FOR_INSN(INSN)  VARRAY_BB (basic_block_for_insn, INSN_UID (INSN))
 237 #define BLOCK_NUM(INSN)       (BLOCK_FOR_INSN (INSN)->index + 0)
 238
 239 extern void compute_bb_for_insn         PROTO ((int));
 240 extern void set_block_for_insn          PROTO ((rtx, basic_block));
 241
 242 extern void dump_bb_data                PROTO ((FILE *, int_list_ptr *,
 243                                                 int_list_ptr *, int));
 244 extern void free_bb_mem                 PROTO ((void));
 245 extern void free_basic_block_vars       PROTO ((int));
 246
 247 extern basic_block split_edge           PROTO ((edge));
 248 extern void insert_insn_on_edge         PROTO ((rtx, edge));
 249 extern void commit_edge_insertions      PROTO ((void));
 250 extern void remove_fake_edges           PROTO ((void));
 251 extern void add_noreturn_fake_exit_edges        PROTO ((void));
 252
 253 /* This structure maintains an edge list vector.  */
 254 struct edge_list
 255 {
 256   int num_blocks;
 257   int num_edges;
 258   edge *index_to_edge;
 259 };
 260
 261 /* This is the value which indicates no edge is present.  */
 262 #define EDGE_INDEX_NO_EDGE      -1
 263
 264 /* EDGE_INDEX returns an integer index for an edge, or EDGE_INDEX_NO_EDGE
 265    if there is no edge between the 2 basic blocks.  */
 266 #define EDGE_INDEX(el, pred, succ) (find_edge_index ((el), (pred), (succ)))
 267
 268 /* INDEX_EDGE_PRED_BB and INDEX_EDGE_SUCC_BB return a pointer to the basic
 269    block which is either the pred or succ end of the indexed edge.  */
 270 #define INDEX_EDGE_PRED_BB(el, index)   ((el)->index_to_edge[(index)]->src)
 271 #define INDEX_EDGE_SUCC_BB(el, index)   ((el)->index_to_edge[(index)]->dest)
 272
 273 /* INDEX_EDGE returns a pointer to the edge.  */
 274 #define INDEX_EDGE(el, index)           ((el)->index_to_edge[(index)])
 275
 276 /* Number of edges in the compressed edge list.  */
 277 #define NUM_EDGES(el)                   ((el)->num_edges)
 278
 279 struct edge_list * create_edge_list     PROTO ((void));
 280 void free_edge_list                     PROTO ((struct edge_list *));
 281 void print_edge_list                    PROTO ((FILE *, struct edge_list *));
 282 void verify_edge_list                   PROTO ((FILE *, struct edge_list *));
 283 int find_edge_index                     PROTO ((struct edge_list *,
 284                                                 basic_block, basic_block));
 285
 286 extern void compute_preds_succs         PROTO ((int_list_ptr *, int_list_ptr *,
 287                                                 int *, int *));
 288 extern void compute_dominators          PROTO ((sbitmap *, sbitmap *,
 289                                                 int_list_ptr *,
 290                                                 int_list_ptr *));
 291 extern void compute_flow_dominators     PROTO ((sbitmap *, sbitmap *));
 292 extern void compute_immediate_dominators        PROTO ((int *, sbitmap *));
 293
 294 /* In lcm.c */
 295 extern void pre_lcm                     PROTO ((int, int, int_list_ptr *,
 296                                                 int_list_ptr *,
 297                                                 sbitmap *, sbitmap *,
 298                                                 sbitmap *, sbitmap *));
 299 extern void pre_rev_lcm                 PROTO ((int, int, int_list_ptr *,
 300                                                 int_list_ptr *,
 301                                                 sbitmap *, sbitmap *,
 302                                                 sbitmap *, sbitmap *));