gcc/tree-alias-common.h

   1 /* Tree based points-to analysis
   2    Copyright (C) 2002, 2003 Free Software Foundation, Inc.
   3    Contributed by Daniel Berlin <dberlin@dberlin.org>
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify
   8 under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2 of the License, or
  10 (at your option) any later version.
  11
  12 GCC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; if not, write to the Free Software
  19 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20 */
  21
  22 #ifndef TREE_ALIAS_COMMON
  23 #define TREE_ALIAS_COMMON
  24
  25 #include "tree-alias-type.h"
  26
  27 /* Alias analysis function pointers.
  28    Functions implemented by the actual alias analysis algorithms in
  29    order for them to work with the common points-to structure.  */
  30 struct tree_alias_ops
  31 {
  32   /* Initialization.
  33      Called right before we start using the other functions.  */
  34   void (*init) (struct tree_alias_ops *);
  35
  36   /* Cleanup.
  37      Called when we are finished with the alias analyzer.  */
  38   void (*cleanup) (struct tree_alias_ops *);
  39
  40   /* Add variable.
  41      Called when we want to inform the alias analyzer about a new
  42      variable we've found.  */
  43   alias_var (*add_var) (struct tree_alias_ops *, tree);
  44
  45   /* Add variable equivalent to existing one.
  46      Called when we want to inform the alias analyzer about a new
  47      variable that has the same points-to set as an existing
  48      variable.  */
  49   alias_var (*add_var_same) (struct tree_alias_ops *, tree,
  50                                  alias_var);
  51
  52   /* Process a simple assignment (a = b).
  53      Called to process simple assignment statements of the form a = b,
  54      where a and b are both variables.  */
  55   void (*simple_assign) (struct tree_alias_ops *, alias_var,
  56                          alias_var);
  57   /* Process an address assignment (a = &b).
  58      Called to process address assignment statements of the form a =
  59      &b, where a and b are both variables.  */
  60   void (*addr_assign) (struct tree_alias_ops *, alias_var, alias_var);
  61
  62   /* Process a pointer assignment (a = *b).
  63      Called to process pointer assignment statements of the form a =
  64      *b, where a and b are both variables.  */
  65   void (*ptr_assign) (struct tree_alias_ops *, alias_var, alias_var);
  66
  67   /* Process an operator assignment (a = op (...))
  68      Called to process operators of the form a = op(...), where a is a
  69      variable.  */
  70   void (*op_assign) (struct tree_alias_ops *, alias_var, varray_type,
  71                      tree, bitmap);
  72   /* Process a heap assignment (a = alloc (...))
  73      Called to process a heap assignment of the form a = alloc
  74      (...), where a is a variable, and *alloc is a function that
  75      returns new memory.  */
  76   void (*heap_assign) (struct tree_alias_ops *, alias_var);
  77
  78   /* Process an assignment to a pointer (*a = b)
  79      Called to process assignment to pointer statements of the form
  80      *a = b, where a and b are both variables.  */
  81   void (*assign_ptr) (struct tree_alias_ops *, alias_var, alias_var);
  82
  83   /* Process a function definition.
  84      Called to inform the alias analyzer about a new function
  85      definition.  */
  86   void (*function_def) (struct tree_alias_ops *, alias_var,
  87                         varray_type, alias_var);
  88
  89   /* Process a function call.
  90      Return 1 if we need to assume conservative side-effects.  */
  91   int (*function_call) (struct tree_alias_ops *, alias_var,
  92                         alias_var, varray_type, bitmap);
  93
  94   /* Determine if two alias variables may alias.   */
  95   bool (*may_alias) (struct tree_alias_ops *, alias_var, alias_var);
  96
  97   /* Determine if two alias variables have the same points-to set.  */
  98   bool (*same_points_to_set) (struct tree_alias_ops *, alias_var,
  99                               alias_var);
 100
 101   /* Determine if the alias variable has an empty points-to set.  */
 102   bool (*empty_points_to_set) (struct tree_alias_ops *, alias_var);
 103
 104   /* Private data.  */
 105   void *data;
 106
 107   /* Interprocedural.  */
 108   unsigned int ip:1;
 109
 110   /* Can do conservative interprocedural analysis if we save the
 111    * info.  */
 112   unsigned int ip_partial:1;
 113
 114 };
 115
 116 extern struct tree_alias_ops *current_alias_ops;
 117 extern void init_alias_vars (void);
 118 extern bool ptr_may_alias_var (tree, tree);
 119 extern bool same_points_to_set (tree, tree);
 120 extern bool empty_points_to_set (tree);
 121 extern const char *alias_get_name (tree);
 122
 123 #endif /* TREE_ALIAS_COMMON */