gcc/ipa-ref.h

   1 /* IPA reference lists.
   2    Copyright (C) 2010-2020 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 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 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   /* speculative id is used to link direct calls with their corresponding
  63      IPA_REF_ADDR references when representing speculative calls.  */
  64   unsigned int speculative_id : 16;
  65   unsigned int referred_index;
  66   ENUM_BITFIELD (ipa_ref_use) use:3;
  67   unsigned int speculative:1;
  68 };
  69
  70 typedef struct ipa_ref ipa_ref_t;
  71 typedef struct ipa_ref *ipa_ref_ptr;
  72
  73
  74 /* List of references.  This is stored in both callgraph and varpool nodes.  */
  75 struct GTY(()) ipa_ref_list
  76 {
  77 public:
  78   /* Return first reference in list or NULL if empty.  */
  79   struct ipa_ref *first_reference (void)
  80   {
  81     if (!vec_safe_length (references))
  82       return NULL;
  83     return &(*references)[0];
  84   }
  85
  86   /* Return first referring ref in list or NULL if empty.  */
  87   struct ipa_ref *first_referring (void)
  88   {
  89     if (!referring.length ())
  90       return NULL;
  91     return referring[0];
  92   }
  93
  94   /* Return first referring alias.  */
  95   struct ipa_ref *first_alias (void)
  96   {
  97     struct ipa_ref *r = first_referring ();
  98
  99     return r && r->use == IPA_REF_ALIAS ? r : NULL;
 100   }
 101
 102   /* Return last referring alias.  */
 103   struct ipa_ref *last_alias (void)
 104   {
 105     unsigned int i = 0;
 106
 107     for(i = 0; i < referring.length (); i++)
 108       if (referring[i]->use != IPA_REF_ALIAS)
 109         break;
 110
 111     return i == 0 ? NULL : referring[i - 1];
 112   }
 113
 114   /* Return true if the symbol has an alias.  */
 115   bool inline has_aliases_p (void)
 116   {
 117     return first_alias ();
 118   }
 119
 120   /* Clear reference list.  */
 121   void clear (void)
 122   {
 123     referring.create (0);
 124     references = NULL;
 125   }
 126
 127   /* Return number of references.  */
 128   unsigned int nreferences (void)
 129   {
 130     return vec_safe_length (references);
 131   }
 132
 133   /* Store actual references in references vector.  */
 134   vec<ipa_ref_t, va_gc> *references;
 135   /* Referring is vector of pointers to references.  It must not live in GGC space
 136      or GGC will try to mark middle of references vectors.  */
 137   vec<ipa_ref_ptr>  GTY((skip)) referring;
 138 };
 139
 140 #endif /* GCC_IPA_REF_H */