gcc/gimple-ssa.h

   1 /* Header file for routines that straddle the border between GIMPLE and
   2    SSA in gimple.
   3    Copyright (C) 2009-2014 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 "hash-map.h"
  25 #include "tree-hasher.h"
  26 #include "tree-ssa-operands.h"
  27
  28 /* This structure is used to map a gimple statement to a label,
  29    or list of labels to represent transaction restart.  */
  30
  31 struct GTY(()) tm_restart_node {
  32   gimple stmt;
  33   tree label_or_list;
  34 };
  35
  36 struct ssa_name_hasher : ggc_hasher<tree>
  37 {
  38   /* Hash a tree in a uid_decl_map.  */
  39
  40   static hashval_t
  41   hash (tree item)
  42   {
  43     return item->ssa_name.var->decl_minimal.uid;
  44   }
  45
  46   /* Return true if the DECL_UID in both trees are equal.  */
  47
  48   static bool
  49   equal (tree a, tree b)
  50 {
  51   return (a->ssa_name.var->decl_minimal.uid == b->ssa_name.var->decl_minimal.uid);
  52 }
  53 };
  54
  55 /* Gimple dataflow datastructure. All publicly available fields shall have
  56    gimple_ accessor defined, all publicly modifiable fields should have
  57    gimple_set accessor.  */
  58 struct GTY(()) gimple_df {
  59   /* A vector of all the noreturn calls passed to modify_stmt.
  60      cleanup_control_flow uses it to detect cases where a mid-block
  61      indirect call has been turned into a noreturn call.  When this
  62      happens, all the instructions after the call are no longer
  63      reachable and must be deleted as dead.  */
  64   vec<gimple, va_gc> *modified_noreturn_calls;
  65
  66   /* Array of all SSA_NAMEs used in the function.  */
  67   vec<tree, va_gc> *ssa_names;
  68
  69   /* Artificial variable used for the virtual operand FUD chain.  */
  70   tree vop;
  71
  72   /* The PTA solution for the ESCAPED artificial variable.  */
  73   struct pt_solution escaped;
  74
  75   /* A map of decls to artificial ssa-names that point to the partition
  76      of the decl.  */
  77   hash_map<tree, tree> * GTY((skip(""))) decls_to_pointers;
  78
  79   /* Free list of SSA_NAMEs.  */
  80   vec<tree, va_gc> *free_ssanames;
  81
  82   /* Hashtable holding definition for symbol.  If this field is not NULL, it
  83      means that the first reference to this variable in the function is a
  84      USE or a VUSE.  In those cases, the SSA renamer creates an SSA name
  85      for this variable with an empty defining statement.  */
  86   hash_table<ssa_name_hasher> *default_defs;
  87
  88   /* True if there are any symbols that need to be renamed.  */
  89   unsigned int ssa_renaming_needed : 1;
  90
  91   /* True if all virtual operands need to be renamed.  */
  92   unsigned int rename_vops : 1;
  93
  94   /* True if the code is in ssa form.  */
  95   unsigned int in_ssa_p : 1;
  96
  97   /* True if IPA points-to information was computed for this function.  */
  98   unsigned int ipa_pta : 1;
  99
 100   struct ssa_operands ssa_operands;
 101
 102   /* Map gimple stmt to tree label (or list of labels) for transaction
 103      restart and abort.  */
 104   htab_t GTY ((param_is (struct tm_restart_node))) tm_restart;
 105 };
 106
 107
 108 /* Return true when gimple SSA form was built.
 109    gimple_in_ssa_p is queried by gimplifier in various early stages before SSA
 110    infrastructure is initialized.  Check for presence of the datastructures
 111    at first place.  */
 112 static inline bool
 113 gimple_in_ssa_p (const struct function *fun)
 114 {
 115   return fun && fun->gimple_df && fun->gimple_df->in_ssa_p;
 116 }
 117
 118 /* Artificial variable used for the virtual operand FUD chain.  */
 119 static inline tree
 120 gimple_vop (const struct function *fun)
 121 {
 122   gcc_checking_assert (fun && fun->gimple_df);
 123   return fun->gimple_df->vop;
 124 }
 125
 126 /* Return the set of VUSE operand for statement G.  */
 127
 128 static inline use_operand_p
 129 gimple_vuse_op (const_gimple g)
 130 {
 131   struct use_optype_d *ops;
 132   const gimple_statement_with_memory_ops *mem_ops_stmt =
 133      dyn_cast <const gimple_statement_with_memory_ops *> (g);
 134   if (!mem_ops_stmt)
 135     return NULL_USE_OPERAND_P;
 136   ops = mem_ops_stmt->use_ops;
 137   if (ops
 138       && USE_OP_PTR (ops)->use == &mem_ops_stmt->vuse)
 139     return USE_OP_PTR (ops);
 140   return NULL_USE_OPERAND_P;
 141 }
 142
 143 /* Return the set of VDEF operand for statement G.  */
 144
 145 static inline def_operand_p
 146 gimple_vdef_op (gimple g)
 147 {
 148   gimple_statement_with_memory_ops *mem_ops_stmt =
 149      dyn_cast <gimple_statement_with_memory_ops *> (g);
 150   if (!mem_ops_stmt)
 151     return NULL_DEF_OPERAND_P;
 152   if (mem_ops_stmt->vdef)
 153     return &mem_ops_stmt->vdef;
 154   return NULL_DEF_OPERAND_P;
 155 }
 156
 157 /* Mark statement S as modified, and update it.  */
 158
 159 static inline void
 160 update_stmt (gimple s)
 161 {
 162   if (gimple_has_ops (s))
 163     {
 164       gimple_set_modified (s, true);
 165       update_stmt_operands (cfun, s);
 166     }
 167 }
 168
 169 /* Update statement S if it has been optimized.  */
 170
 171 static inline void
 172 update_stmt_if_modified (gimple s)
 173 {
 174   if (gimple_modified_p (s))
 175     update_stmt_operands (cfun, s);
 176 }
 177
 178 /* Mark statement S as modified, and update it.  */
 179
 180 static inline void
 181 update_stmt_fn (struct function *fn, gimple s)
 182 {
 183   if (gimple_has_ops (s))
 184     {
 185       gimple_set_modified (s, true);
 186       update_stmt_operands (fn, s);
 187     }
 188 }
 189
 190
 191 #endif /* GCC_GIMPLE_SSA_H */