gcc/basic-block.h

   1 /* Define control and data flow tables, and regsets.
   2    Copyright (C) 1987 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 /* Number of bits in each actual element of a regset.  */
  23
  24 #define REGSET_ELT_BITS HOST_BITS_PER_WIDE_INT
  25
  26 /* Type to use for a regset element.  Note that lots of code assumes
  27    that the initial part of a regset that contains information on the
  28    hard registers is the same format as a HARD_REG_SET.  */
  29
  30 #define REGSET_ELT_TYPE unsigned HOST_WIDE_INT
  31
  32 /* Define the type for a pointer to a set with a bit for each
  33    (hard or pseudo) register.  */
  34
  35 typedef REGSET_ELT_TYPE *regset;
  36
  37 /* Size of a regset for the current function,
  38    in (1) bytes and (2) elements.  */
  39
  40 extern int regset_bytes;
  41 extern int regset_size;
  42
  43 /* Number of basic blocks in the current function.  */
  44
  45 extern int n_basic_blocks;
  46
  47 /* Index by basic block number, get first insn in the block.  */
  48
  49 extern rtx *basic_block_head;
  50
  51 /* Index by basic block number, get last insn in the block.  */
  52
  53 extern rtx *basic_block_end;
  54
  55 /* Index by basic block number, get address of regset
  56    describing the registers live at the start of that block.  */
  57
  58 extern regset *basic_block_live_at_start;
  59
  60 /* Indexed by n, gives number of basic block that  (REG n) is used in.
  61    If the value is REG_BLOCK_GLOBAL (-2),
  62    it means (REG n) is used in more than one basic block.
  63    REG_BLOCK_UNKNOWN (-1) means it hasn't been seen yet so we don't know.
  64    This information remains valid for the rest of the compilation
  65    of the current function; it is used to control register allocation.  */
  66
  67 #define REG_BLOCK_UNKNOWN -1
  68 #define REG_BLOCK_GLOBAL -2
  69 extern int *reg_basic_block;