gcc/ipa-ref.h

   1 /* IPA reference lists.
   2    Copyright (C) 2010-2014 Free Software Foundation, Inc.
   3    Contributed by Jan Hubicka
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 3, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 #ifndef GCC_IPA_REF_H
  22 #define GCC_IPA_REF_H
  23
  24 struct cgraph_node;
  25 class varpool_node;
  26 class symtab_node;
  27
  28
  29 /* How the reference is done.  */
  30 enum GTY(()) ipa_ref_use
  31 {
  32   IPA_REF_LOAD,
  33   IPA_REF_STORE,
  34   IPA_REF_ADDR,
  35   IPA_REF_ALIAS
  36 };
  37
  38 /* Record of reference in callgraph or varpool.  */
  39 struct GTY(()) ipa_ref
  40 {
  41 public:
  42   /* Remove reference.  */
  43   void remove_reference ();
  44
  45   /* Return true when execution of reference can lead to return from
  46      function.  */
  47   bool cannot_lead_to_return ();
  48
  49   /* Return reference list this reference is in.  */
  50   struct ipa_ref_list * referring_ref_list (void);
  51
  52   /* Return reference list this reference is in.  */
  53   struct ipa_ref_list * referred_ref_list (void);
  54
  55   symtab_node *referring;
  56   symtab_node *referred;
  57   gimple stmt;
  58   unsigned int lto_stmt_uid;
  59   unsigned int referred_index;
  60   ENUM_BITFIELD (ipa_ref_use) use:2;
  61   unsigned int speculative:1;
  62 };
  63
  64 typedef struct ipa_ref ipa_ref_t;
  65 typedef struct ipa_ref *ipa_ref_ptr;
  66
  67
  68 /* List of references.  This is stored in both callgraph and varpool nodes.  */
  69 struct GTY(()) ipa_ref_list
  70 {
  71 public:
  72   /* Return first reference in list or NULL if empty.  */
  73   struct ipa_ref *first_reference (void)
  74   {
  75     if (!vec_safe_length (references))
  76       return NULL;
  77     return &(*references)[0];
  78   }
  79
  80   /* Return first referring ref in list or NULL if empty.  */
  81   struct ipa_ref *first_referring (void)
  82   {
  83     if (!referring.length ())
  84       return NULL;
  85     return referring[0];
  86   }
  87
  88   /* Return first referring alias.  */
  89   struct ipa_ref *first_alias (void)
  90   {
  91     struct ipa_ref *r = first_referring ();
  92
  93     return r && r->use == IPA_REF_ALIAS ? r : NULL;
  94   }
  95
  96   /* Return last referring alias.  */
  97   struct ipa_ref *last_alias (void)
  98   {
  99     unsigned int i = 0;
 100
 101     for(i = 0; i < referring.length (); i++)
 102       if (referring[i]->use != IPA_REF_ALIAS)
 103         break;
 104
 105     return i == 0 ? NULL : referring[i - 1];
 106   }
 107
 108   /* Return true if the symbol has an alias.  */
 109   bool inline has_aliases_p (void)
 110   {
 111     return first_alias ();
 112   }
 113
 114   /* Clear reference list.  */
 115   void clear (void)
 116   {
 117     referring.create (0);
 118     references = NULL;
 119   }
 120
 121   /* Return number of references.  */
 122   unsigned int nreferences (void)
 123   {
 124     return vec_safe_length (references);
 125   }
 126
 127   /* Store actual references in references vector.  */
 128   vec<ipa_ref_t, va_gc> *references;
 129   /* Referring is vector of pointers to references.  It must not live in GGC space
 130      or GGC will try to mark middle of references vectors.  */
 131   vec<ipa_ref_ptr>  GTY((skip)) referring;
 132 };
 133
 134 #endif /* GCC_IPA_REF_H */