gcc/ipa-ref.h

   1 /* IPA reference lists.
   2    Copyright (C) 2010-2017 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 true if refernece may be used in address compare.  */
  51   bool address_matters_p ();
  52
  53   /* Return reference list this reference is in.  */
  54   struct ipa_ref_list * referring_ref_list (void);
  55
  56   /* Return reference list this reference is in.  */
  57   struct ipa_ref_list * referred_ref_list (void);
  58
  59   symtab_node *referring;
  60   symtab_node *referred;
  61   gimple *stmt;
  62   unsigned int lto_stmt_uid;
  63   unsigned int referred_index;
  64   ENUM_BITFIELD (ipa_ref_use) use:3;
  65   unsigned int speculative:1;
  66 };
  67
  68 typedef struct ipa_ref ipa_ref_t;
  69 typedef struct ipa_ref *ipa_ref_ptr;
  70
  71
  72 /* List of references.  This is stored in both callgraph and varpool nodes.  */
  73 struct GTY(()) ipa_ref_list
  74 {
  75 public:
  76   /* Return first reference in list or NULL if empty.  */
  77   struct ipa_ref *first_reference (void)
  78   {
  79     if (!vec_safe_length (references))
  80       return NULL;
  81     return &(*references)[0];
  82   }
  83
  84   /* Return first referring ref in list or NULL if empty.  */
  85   struct ipa_ref *first_referring (void)
  86   {
  87     if (!referring.length ())
  88       return NULL;
  89     return referring[0];
  90   }
  91
  92   /* Return first referring alias.  */
  93   struct ipa_ref *first_alias (void)
  94   {
  95     struct ipa_ref *r = first_referring ();
  96
  97     return r && r->use == IPA_REF_ALIAS ? r : NULL;
  98   }
  99
 100   /* Return last referring alias.  */
 101   struct ipa_ref *last_alias (void)
 102   {
 103     unsigned int i = 0;
 104
 105     for(i = 0; i < referring.length (); i++)
 106       if (referring[i]->use != IPA_REF_ALIAS)
 107         break;
 108
 109     return i == 0 ? NULL : referring[i - 1];
 110   }
 111
 112   /* Return true if the symbol has an alias.  */
 113   bool inline has_aliases_p (void)
 114   {
 115     return first_alias ();
 116   }
 117
 118   /* Clear reference list.  */
 119   void clear (void)
 120   {
 121     referring.create (0);
 122     references = NULL;
 123   }
 124
 125   /* Return number of references.  */
 126   unsigned int nreferences (void)
 127   {
 128     return vec_safe_length (references);
 129   }
 130
 131   /* Store actual references in references vector.  */
 132   vec<ipa_ref_t, va_gc> *references;
 133   /* Referring is vector of pointers to references.  It must not live in GGC space
 134      or GGC will try to mark middle of references vectors.  */
 135   vec<ipa_ref_ptr>  GTY((skip)) referring;
 136 };
 137
 138 #endif /* GCC_IPA_REF_H */