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   /* Hashtable holding definition for symbol.  If this field is not NULL, it
  94      means that the first reference to this variable in the function is a
  95      USE or a VUSE.  In those cases, the SSA renamer creates an SSA name
  96      for this variable with an empty defining statement.  */
  97   hash_table<ssa_name_hasher> *default_defs;
  98
  99   /* True if there are any symbols that need to be renamed.  */
 100   unsigned int ssa_renaming_needed : 1;
 101
 102   /* True if all virtual operands need to be renamed.  */
 103   unsigned int rename_vops : 1;
 104
 105   /* True if the code is in ssa form.  */
 106   unsigned int in_ssa_p : 1;
 107
 108   /* True if IPA points-to information was computed for this function.  */
 109   unsigned int ipa_pta : 1;
 110
 111   struct ssa_operands ssa_operands;
 112
 113   /* Map gimple stmt to tree label (or list of labels) for transaction
 114      restart and abort.  */
 115   hash_table<tm_restart_hasher> *tm_restart;
 116 };
 117
 118
 119 /* Return true when gimple SSA form was built.
 120    gimple_in_ssa_p is queried by gimplifier in various early stages before SSA
 121    infrastructure is initialized.  Check for presence of the datastructures
 122    at first place.  */
 123 static inline bool
 124 gimple_in_ssa_p (const struct function *fun)
 125 {
 126   return fun && fun->gimple_df && fun->gimple_df->in_ssa_p;
 127 }
 128
 129 /* Artificial variable used for the virtual operand FUD chain.  */
 130 static inline tree
 131 gimple_vop (const struct function *fun)
 132 {
 133   gcc_checking_assert (fun && fun->gimple_df);
 134   return fun->gimple_df->vop;
 135 }
 136
 137 /* Return the set of VUSE operand for statement G.  */
 138
 139 static inline use_operand_p
 140 gimple_vuse_op (const_gimple g)
 141 {
 142   struct use_optype_d *ops;
 143   const gimple_statement_with_memory_ops *mem_ops_stmt =
 144      dyn_cast <const gimple_statement_with_memory_ops *> (g);
 145   if (!mem_ops_stmt)
 146     return NULL_USE_OPERAND_P;
 147   ops = mem_ops_stmt->use_ops;
 148   if (ops
 149       && USE_OP_PTR (ops)->use == &mem_ops_stmt->vuse)
 150     return USE_OP_PTR (ops);
 151   return NULL_USE_OPERAND_P;
 152 }
 153
 154 /* Return the set of VDEF operand for statement G.  */
 155
 156 static inline def_operand_p
 157 gimple_vdef_op (gimple g)
 158 {
 159   gimple_statement_with_memory_ops *mem_ops_stmt =
 160      dyn_cast <gimple_statement_with_memory_ops *> (g);
 161   if (!mem_ops_stmt)
 162     return NULL_DEF_OPERAND_P;
 163   if (mem_ops_stmt->vdef)
 164     return &mem_ops_stmt->vdef;
 165   return NULL_DEF_OPERAND_P;
 166 }
 167
 168 /* Mark statement S as modified, and update it.  */
 169
 170 static inline void
 171 update_stmt (gimple s)
 172 {
 173   if (gimple_has_ops (s))
 174     {
 175       gimple_set_modified (s, true);
 176       update_stmt_operands (cfun, s);
 177     }
 178 }
 179
 180 /* Update statement S if it has been optimized.  */
 181
 182 static inline void
 183 update_stmt_if_modified (gimple s)
 184 {
 185   if (gimple_modified_p (s))
 186     update_stmt_operands (cfun, s);
 187 }
 188
 189 /* Mark statement S as modified, and update it.  */
 190
 191 static inline void
 192 update_stmt_fn (struct function *fn, gimple s)
 193 {
 194   if (gimple_has_ops (s))
 195     {
 196       gimple_set_modified (s, true);
 197       update_stmt_operands (fn, s);
 198     }
 199 }
 200
 201
 202 #endif /* GCC_GIMPLE_SSA_H */