gcc/ipa-ref.h

   1 /* IPA reference lists.
   2    Copyright (C) 2010-2018 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 true if refernece may be used in address compare.  */
  50   bool address_matters_p ();
  51
  52   /* Return reference list this reference is in.  */
  53   struct ipa_ref_list * referring_ref_list (void);
  54
  55   /* Return reference list this reference is in.  */
  56   struct ipa_ref_list * referred_ref_list (void);
  57
  58   symtab_node *referring;
  59   symtab_node *referred;
  60   gimple *stmt;
  61   unsigned int lto_stmt_uid;
  62   unsigned int referred_index;
  63   ENUM_BITFIELD (ipa_ref_use) use:3;
  64   unsigned int speculative:1;
  65 };
  66
  67 typedef struct ipa_ref ipa_ref_t;
  68 typedef struct ipa_ref *ipa_ref_ptr;
  69
  70
  71 /* List of references.  This is stored in both callgraph and varpool nodes.  */
  72 struct GTY(()) ipa_ref_list
  73 {
  74 public:
  75   /* Return first reference in list or NULL if empty.  */
  76   struct ipa_ref *first_reference (void)
  77   {
  78     if (!vec_safe_length (references))
  79       return NULL;
  80     return &(*references)[0];
  81   }
  82
  83   /* Return first referring ref in list or NULL if empty.  */
  84   struct ipa_ref *first_referring (void)
  85   {
  86     if (!referring.length ())
  87       return NULL;
  88     return referring[0];
  89   }
  90
  91   /* Return first referring alias.  */
  92   struct ipa_ref *first_alias (void)
  93   {
  94     struct ipa_ref *r = first_referring ();
  95
  96     return r && r->use == IPA_REF_ALIAS ? r : NULL;
  97   }
  98
  99   /* Return last referring alias.  */
 100   struct ipa_ref *last_alias (void)
 101   {
 102     unsigned int i = 0;
 103
 104     for(i = 0; i < referring.length (); i++)
 105       if (referring[i]->use != IPA_REF_ALIAS)
 106         break;
 107
 108     return i == 0 ? NULL : referring[i - 1];
 109   }
 110
 111   /* Return true if the symbol has an alias.  */
 112   bool inline has_aliases_p (void)
 113   {
 114     return first_alias ();
 115   }
 116
 117   /* Clear reference list.  */
 118   void clear (void)
 119   {
 120     referring.create (0);
 121     references = NULL;
 122   }
 123
 124   /* Return number of references.  */
 125   unsigned int nreferences (void)
 126   {
 127     return vec_safe_length (references);
 128   }
 129
 130   /* Store actual references in references vector.  */
 131   vec<ipa_ref_t, va_gc> *references;
 132   /* Referring is vector of pointers to references.  It must not live in GGC space
 133      or GGC will try to mark middle of references vectors.  */
 134   vec<ipa_ref_ptr>  GTY((skip)) referring;
 135 };
 136
 137 #endif /* GCC_IPA_REF_H */