gcc/ipa-ref.h

   1 /* IPA reference lists.
   2    Copyright (C) 2010-2021 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 struct varpool_node;
  26 struct symtab_node;
  27
  28
  29 /* How the reference is done.  */
  30 enum 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 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 reference 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   /* speculative id is used to link direct calls with their corresponding
  64      IPA_REF_ADDR references when representing speculative calls.  */
  65   unsigned int speculative_id : 16;
  66   ENUM_BITFIELD (ipa_ref_use) use:3;
  67   unsigned int speculative:1;
  68 };
  69
  70 typedef struct ipa_ref ipa_ref_t;
  71
  72
  73 /* List of references.  This is stored in both callgraph and varpool nodes.  */
  74 struct ipa_ref_list
  75 {
  76 public:
  77   /* Return first reference in list or NULL if empty.  */
  78   struct ipa_ref *first_reference (void)
  79   {
  80     if (!references.length ())
  81       return NULL;
  82     return &references[0];
  83   }
  84
  85   /* Return first referring ref in list or NULL if empty.  */
  86   struct ipa_ref *first_referring (void)
  87   {
  88     if (!referring.length ())
  89       return NULL;
  90     return referring[0];
  91   }
  92
  93   /* Return first referring alias.  */
  94   struct ipa_ref *first_alias (void)
  95   {
  96     struct ipa_ref *r = first_referring ();
  97
  98     return r && r->use == IPA_REF_ALIAS ? r : NULL;
  99   }
 100
 101   /* Return last referring alias.  */
 102   struct ipa_ref *last_alias (void)
 103   {
 104     unsigned int i = 0;
 105
 106     for(i = 0; i < referring.length (); i++)
 107       if (referring[i]->use != IPA_REF_ALIAS)
 108         break;
 109
 110     return i == 0 ? NULL : referring[i - 1];
 111   }
 112
 113   /* Return true if the symbol has an alias.  */
 114   bool inline has_aliases_p (void)
 115   {
 116     return first_alias ();
 117   }
 118
 119   /* Clear reference list.  */
 120   void clear (void)
 121   {
 122     referring.create (0);
 123     references.create (0);
 124   }
 125
 126   /* Return number of references.  */
 127   unsigned int nreferences (void)
 128   {
 129     return references.length ();
 130   }
 131
 132   /* Store actual references in references vector.  */
 133   vec<ipa_ref_t, va_heap, vl_ptr> references;
 134   /* Referring is vector of pointers to references.  It must not live in GGC space
 135      or GGC will try to mark middle of references vectors.  */
 136   vec<ipa_ref_t *, va_heap, vl_ptr> referring;
 137 };
 138
 139 #endif /* GCC_IPA_REF_H */