gcc/gimple-ssa.h

   1 /* Header file for routines that straddle the border between GIMPLE and
   2    SSA in gimple.
   3    Copyright (C) 2009-2015 Free Software Foundation, Inc.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 3, or (at your option)
  10 any later version.
  11
  12 GCC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License 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_GIMPLE_SSA_H
  22 #define GCC_GIMPLE_SSA_H
  23
  24 #include "tree-ssa-operands.h"
  25
  26 /* This structure is used to map a gimple statement to a label,
  27    or list of labels to represent transaction restart.  */
  28
  29 struct GTY((for_user)) tm_restart_node {
  30   gimple *stmt;
  31   tree label_or_list;
  32 };
  33
  34 /* Hasher for tm_restart_node.  */
  35
  36 struct tm_restart_hasher : ggc_ptr_hash<tm_restart_node>
  37 {
  38   static hashval_t hash (tm_restart_node *n) { return htab_hash_pointer (n); }
  39
  40   static bool
  41   equal (tm_restart_node *a, tm_restart_node *b)
  42   {
  43     return a == b;
  44   }
  45 };
  46
  47 struct ssa_name_hasher : ggc_ptr_hash<tree_node>
  48 {
  49   /* Hash a tree in a uid_decl_map.  */
  50
  51   static hashval_t
  52   hash (tree item)
  53   {
  54     return item->ssa_name.var->decl_minimal.uid;
  55   }
  56
  57   /* Return true if the DECL_UID in both trees are equal.  */
  58
  59   static bool
  60   equal (tree a, tree b)
  61 {
  62   return (a->ssa_name.var->decl_minimal.uid == b->ssa_name.var->decl_minimal.uid);
  63 }
  64 };
  65
  66 /* Gimple dataflow datastructure. All publicly available fields shall have
  67    gimple_ accessor defined, all publicly modifiable fields should have
  68    gimple_set accessor.  */
  69 struct GTY(()) gimple_df {
  70   /* A vector of all the noreturn calls passed to modify_stmt.
  71      cleanup_control_flow uses it to detect cases where a mid-block
  72      indirect call has been turned into a noreturn call.  When this
  73      happens, all the instructions after the call are no longer
  74      reachable and must be deleted as dead.  */
  75   vec<gimple *, va_gc> *modified_noreturn_calls;
  76
  77   /* Array of all SSA_NAMEs used in the function.  */
  78   vec<tree, va_gc> *ssa_names;
  79
  80   /* Artificial variable used for the virtual operand FUD chain.  */
  81   tree vop;
  82
  83   /* The PTA solution for the ESCAPED artificial variable.  */
  84   struct pt_solution escaped;
  85
  86   /* A map of decls to artificial ssa-names that point to the partition
  87      of the decl.  */
  88   hash_map<tree, tree> * GTY((skip(""))) decls_to_pointers;
  89
  90   /* Free list of SSA_NAMEs.  */
  91   vec<tree, va_gc> *free_ssanames;
  92
  93   /* Queue of SSA_NAMEs to be freed at the next opportunity.  */
  94   vec<tree, va_gc> *free_ssanames_queue;
  95
  96   /* Hashtable holding definition for symbol.  If this field is not NULL, it
  97      means that the first reference to this variable in the function is a
  98      USE or a VUSE.  In those cases, the SSA renamer creates an SSA name
  99      for this variable with an empty defining statement.  */
 100   hash_table<ssa_name_hasher> *default_defs;
 101
 102   /* True if there are any symbols that need to be renamed.  */
 103   unsigned int ssa_renaming_needed : 1;
 104
 105   /* True if all virtual operands need to be renamed.  */
 106   unsigned int rename_vops : 1;
 107
 108   /* True if the code is in ssa form.  */
 109   unsigned int in_ssa_p : 1;
 110
 111   /* True if IPA points-to information was computed for this function.  */
 112   unsigned int ipa_pta : 1;
 113
 114   struct ssa_operands ssa_operands;
 115
 116   /* Map gimple stmt to tree label (or list of labels) for transaction
 117      restart and abort.  */
 118   hash_table<tm_restart_hasher> *tm_restart;
 119 };
 120
 121
 122 /* Return true when gimple SSA form was built.
 123    gimple_in_ssa_p is queried by gimplifier in various early stages before SSA
 124    infrastructure is initialized.  Check for presence of the datastructures
 125    at first place.  */
 126 static inline bool
 127 gimple_in_ssa_p (const struct function *fun)
 128 {
 129   return fun && fun->gimple_df && fun->gimple_df->in_ssa_p;
 130 }
 131
 132 /* Artificial variable used for the virtual operand FUD chain.  */
 133 static inline tree
 134 gimple_vop (const struct function *fun)
 135 {
 136   gcc_checking_assert (fun && fun->gimple_df);
 137   return fun->gimple_df->vop;
 138 }
 139
 140 /* Return the set of VUSE operand for statement G.  */
 141
 142 static inline use_operand_p
 143 gimple_vuse_op (const gimple *g)
 144 {
 145   struct use_optype_d *ops;
 146   const gimple_statement_with_memory_ops *mem_ops_stmt =
 147      dyn_cast <const gimple_statement_with_memory_ops *> (g);
 148   if (!mem_ops_stmt)
 149     return NULL_USE_OPERAND_P;
 150   ops = mem_ops_stmt->use_ops;
 151   if (ops
 152       && USE_OP_PTR (ops)->use == &mem_ops_stmt->vuse)
 153     return USE_OP_PTR (ops);
 154   return NULL_USE_OPERAND_P;
 155 }
 156
 157 /* Return the set of VDEF operand for statement G.  */
 158
 159 static inline def_operand_p
 160 gimple_vdef_op (gimple *g)
 161 {
 162   gimple_statement_with_memory_ops *mem_ops_stmt =
 163      dyn_cast <gimple_statement_with_memory_ops *> (g);
 164   if (!mem_ops_stmt)
 165     return NULL_DEF_OPERAND_P;
 166   if (mem_ops_stmt->vdef)
 167     return &mem_ops_stmt->vdef;
 168   return NULL_DEF_OPERAND_P;
 169 }
 170
 171 /* Mark statement S as modified, and update it.  */
 172
 173 static inline void
 174 update_stmt (gimple *s)
 175 {
 176   if (gimple_has_ops (s))
 177     {
 178       gimple_set_modified (s, true);
 179       update_stmt_operands (cfun, s);
 180     }
 181 }
 182
 183 /* Update statement S if it has been optimized.  */
 184
 185 static inline void
 186 update_stmt_if_modified (gimple *s)
 187 {
 188   if (gimple_modified_p (s))
 189     update_stmt_operands (cfun, s);
 190 }
 191
 192 /* Mark statement S as modified, and update it.  */
 193
 194 static inline void
 195 update_stmt_fn (struct function *fn, gimple *s)
 196 {
 197   if (gimple_has_ops (s))
 198     {
 199       gimple_set_modified (s, true);
 200       update_stmt_operands (fn, s);
 201     }
 202 }
 203
 204
 205 #endif /* GCC_GIMPLE_SSA_H */