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, 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20
  21 /* Number of bits in each actual element of a regset.  */
  22
  23 #define REGSET_ELT_BITS HOST_BITS_PER_WIDE_INT
  24
  25 /* Type to use for a regset element.  Note that lots of code assumes
  26    that the initial part of a regset that contains information on the
  27    hard registers is the same format as a HARD_REG_SET.  */
  28
  29 #define REGSET_ELT_TYPE unsigned HOST_WIDE_INT
  30
  31 /* Define the type for a pointer to a set with a bit for each
  32    (hard or pseudo) register.  */
  33
  34 typedef REGSET_ELT_TYPE *regset;
  35
  36 /* Size of a regset for the current function,
  37    in (1) bytes and (2) elements.  */
  38
  39 extern int regset_bytes;
  40 extern int regset_size;
  41
  42 /* Number of basic blocks in the current function.  */
  43
  44 extern int n_basic_blocks;
  45
  46 /* Index by basic block number, get first insn in the block.  */
  47
  48 extern rtx *basic_block_head;
  49
  50 /* Index by basic block number, get last insn in the block.  */
  51
  52 extern rtx *basic_block_end;
  53
  54 /* Index by basic block number, get address of regset
  55    describing the registers live at the start of that block.  */
  56
  57 extern regset *basic_block_live_at_start;
  58
  59 /* Indexed by n, gives number of basic block that  (REG n) is used in.
  60    If the value is REG_BLOCK_GLOBAL (-2),
  61    it means (REG n) is used in more than one basic block.
  62    REG_BLOCK_UNKNOWN (-1) means it hasn't been seen yet so we don't know.
  63    This information remains valid for the rest of the compilation
  64    of the current function; it is used to control register allocation.  */
  65
  66 #define REG_BLOCK_UNKNOWN -1
  67 #define REG_BLOCK_GLOBAL -2
  68 extern int *reg_basic_block;