gcc/ipa-ref.h

   1 /* IPA reference lists.
   2    Copyright (C) 2010-2015 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   IPA_REF_CHKP
  37 };
  38
  39 /* Record of reference in callgraph or varpool.  */
  40 struct GTY(()) ipa_ref
  41 {
  42 public:
  43   /* Remove reference.  */
  44   void remove_reference ();
  45
  46   /* Return true when execution of reference can lead to return from
  47      function.  */
  48   bool cannot_lead_to_return ();
  49
  50   /* Return reference list this reference is in.  */
  51   struct ipa_ref_list * referring_ref_list (void);
  52
  53   /* Return reference list this reference is in.  */
  54   struct ipa_ref_list * referred_ref_list (void);
  55
  56   symtab_node *referring;
  57   symtab_node *referred;
  58   gimple stmt;
  59   unsigned int lto_stmt_uid;
  60   unsigned int referred_index;
  61   ENUM_BITFIELD (ipa_ref_use) use:3;
  62   unsigned int speculative:1;
  63 };
  64
  65 typedef struct ipa_ref ipa_ref_t;
  66 typedef struct ipa_ref *ipa_ref_ptr;
  67
  68
  69 /* List of references.  This is stored in both callgraph and varpool nodes.  */
  70 struct GTY(()) ipa_ref_list
  71 {
  72 public:
  73   /* Return first reference in list or NULL if empty.  */
  74   struct ipa_ref *first_reference (void)
  75   {
  76     if (!vec_safe_length (references))
  77       return NULL;
  78     return &(*references)[0];
  79   }
  80
  81   /* Return first referring ref in list or NULL if empty.  */
  82   struct ipa_ref *first_referring (void)
  83   {
  84     if (!referring.length ())
  85       return NULL;
  86     return referring[0];
  87   }
  88
  89   /* Return first referring alias.  */
  90   struct ipa_ref *first_alias (void)
  91   {
  92     struct ipa_ref *r = first_referring ();
  93
  94     return r && r->use == IPA_REF_ALIAS ? r : NULL;
  95   }
  96
  97   /* Return last referring alias.  */
  98   struct ipa_ref *last_alias (void)
  99   {
 100     unsigned int i = 0;
 101
 102     for(i = 0; i < referring.length (); i++)
 103       if (referring[i]->use != IPA_REF_ALIAS)
 104         break;
 105
 106     return i == 0 ? NULL : referring[i - 1];
 107   }
 108
 109   /* Return true if the symbol has an alias.  */
 110   bool inline has_aliases_p (void)
 111   {
 112     return first_alias ();
 113   }
 114
 115   /* Clear reference list.  */
 116   void clear (void)
 117   {
 118     referring.create (0);
 119     references = NULL;
 120   }
 121
 122   /* Return number of references.  */
 123   unsigned int nreferences (void)
 124   {
 125     return vec_safe_length (references);
 126   }
 127
 128   /* Store actual references in references vector.  */
 129   vec<ipa_ref_t, va_gc> *references;
 130   /* Referring is vector of pointers to references.  It must not live in GGC space
 131      or GGC will try to mark middle of references vectors.  */
 132   vec<ipa_ref_ptr>  GTY((skip)) referring;
 133 };
 134
 135 #endif /* GCC_IPA_REF_H */