gcc/ssaexpand.h

   1 /* Routines for expanding from SSA form to RTL.
   2    Copyright (C) 2009 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
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 3, or (at your option)
   9 any later version.
  10
  11 GCC 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 GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20
  21 #ifndef _SSAEXPAND_H
  22 #define _SSAEXPAND_H 1
  23
  24 #include "tree-ssa-live.h"
  25
  26 /* This structure (of which only a singleton SA exists) is used to
  27    pass around information between the outof-SSA functions, cfgexpand
  28    and expand itself.  */
  29 struct ssaexpand
  30 {
  31   /* The computed partitions of SSA names are stored here.  */
  32   var_map map;
  33
  34   /* For an SSA name version V bit V is set iff TER decided that
  35      its definition should be forwarded.  */
  36   bitmap values;
  37
  38   /* For a partition number I partition_to_pseudo[I] contains the
  39      RTL expression of the allocated space of it (either a MEM or
  40      a pseudos REG).  */
  41   rtx *partition_to_pseudo;
  42
  43   /* If partition I contains an SSA name that has a default def,
  44      bit I will be set in this bitmap.  */
  45   bitmap partition_has_default_def;
  46 };
  47
  48 /* This is the singleton described above.  */
  49 extern struct ssaexpand SA;
  50
  51 /* Returns the RTX expression representing the storage of the outof-SSA
  52    partition that the SSA name EXP is a member of.  */
  53 static inline rtx
  54 get_rtx_for_ssa_name (tree exp)
  55 {
  56   int p = partition_find (SA.map->var_partition, SSA_NAME_VERSION (exp));
  57   if (SA.map->partition_to_view)
  58     p = SA.map->partition_to_view[p];
  59   gcc_assert (p != NO_PARTITION);
  60   return SA.partition_to_pseudo[p];
  61 }
  62
  63 /* If TER decided to forward the definition of SSA name EXP this function
  64    returns the defining statement, otherwise NULL.  */
  65 static inline gimple
  66 get_gimple_for_ssa_name (tree exp)
  67 {
  68   int v = SSA_NAME_VERSION (exp);
  69   if (SA.values && bitmap_bit_p (SA.values, v))
  70     return SSA_NAME_DEF_STMT (exp);
  71   return NULL;
  72 }
  73
  74 /* In tree-outof-ssa.c.  */
  75 void finish_out_of_ssa (struct ssaexpand *sa);
  76 unsigned int rewrite_out_of_ssa (struct ssaexpand *sa);
  77 void expand_phi_nodes (struct ssaexpand *sa);
  78
  79 #endif