gcc/gimple-streamer-out.c

   1 /* Routines for emitting GIMPLE to a file stream.
   2
   3    Copyright (C) 2011-2015 Free Software Foundation, Inc.
   4    Contributed by Diego Novillo <dnovillo@google.com>
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 3, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22 #include "config.h"
  23 #include "system.h"
  24 #include "coretypes.h"
  25 #include "alias.h"
  26 #include "backend.h"
  27 #include "tree.h"
  28 #include "gimple.h"
  29 #include "hard-reg-set.h"
  30 #include "options.h"
  31 #include "fold-const.h"
  32 #include "internal-fn.h"
  33 #include "tree-eh.h"
  34 #include "gimple-iterator.h"
  35 #include "gimple-ssa.h"
  36 #include "cgraph.h"
  37 #include "gimple-streamer.h"
  38 #include "value-prof.h"
  39
  40 /* Output PHI function PHI to the main stream in OB.  */
  41
  42 static void
  43 output_phi (struct output_block *ob, gphi *phi)
  44 {
  45   unsigned i, len = gimple_phi_num_args (phi);
  46
  47   streamer_write_record_start (ob, lto_gimple_code_to_tag (GIMPLE_PHI));
  48   streamer_write_uhwi (ob, SSA_NAME_VERSION (PHI_RESULT (phi)));
  49
  50   for (i = 0; i < len; i++)
  51     {
  52       stream_write_tree (ob, gimple_phi_arg_def (phi, i), true);
  53       streamer_write_uhwi (ob, gimple_phi_arg_edge (phi, i)->src->index);
  54       bitpack_d bp = bitpack_create (ob->main_stream);
  55       stream_output_location (ob, &bp, gimple_phi_arg_location (phi, i));
  56       streamer_write_bitpack (&bp);
  57     }
  58 }
  59
  60
  61 /* Emit statement STMT on the main stream of output block OB.  */
  62
  63 static void
  64 output_gimple_stmt (struct output_block *ob, gimple stmt)
  65 {
  66   unsigned i;
  67   enum gimple_code code;
  68   enum LTO_tags tag;
  69   struct bitpack_d bp;
  70   histogram_value hist;
  71
  72   /* Emit identifying tag.  */
  73   code = gimple_code (stmt);
  74   tag = lto_gimple_code_to_tag (code);
  75   streamer_write_record_start (ob, tag);
  76
  77   /* Emit the tuple header.  */
  78   bp = bitpack_create (ob->main_stream);
  79   bp_pack_var_len_unsigned (&bp, gimple_num_ops (stmt));
  80   bp_pack_value (&bp, gimple_no_warning_p (stmt), 1);
  81   if (is_gimple_assign (stmt))
  82     bp_pack_value (&bp,
  83                    gimple_assign_nontemporal_move_p (
  84                      as_a <gassign *> (stmt)),
  85                    1);
  86   bp_pack_value (&bp, gimple_has_volatile_ops (stmt), 1);
  87   hist = gimple_histogram_value (cfun, stmt);
  88   bp_pack_value (&bp, hist != NULL, 1);
  89   bp_pack_var_len_unsigned (&bp, stmt->subcode);
  90
  91   /* Emit location information for the statement.  */
  92   stream_output_location (ob, &bp, LOCATION_LOCUS (gimple_location (stmt)));
  93   streamer_write_bitpack (&bp);
  94
  95   /* Emit the lexical block holding STMT.  */
  96   stream_write_tree (ob, gimple_block (stmt), true);
  97
  98   /* Emit the operands.  */
  99   switch (gimple_code (stmt))
 100     {
 101     case GIMPLE_RESX:
 102       streamer_write_hwi (ob, gimple_resx_region (as_a <gresx *> (stmt)));
 103       break;
 104
 105     case GIMPLE_EH_MUST_NOT_THROW:
 106       stream_write_tree (ob,
 107                          gimple_eh_must_not_throw_fndecl (
 108                            as_a <geh_mnt *> (stmt)),
 109                          true);
 110       break;
 111
 112     case GIMPLE_EH_DISPATCH:
 113       streamer_write_hwi (ob,
 114                           gimple_eh_dispatch_region (
 115                             as_a <geh_dispatch *> (stmt)));
 116       break;
 117
 118     case GIMPLE_ASM:
 119       {
 120         gasm *asm_stmt = as_a <gasm *> (stmt);
 121         streamer_write_uhwi (ob, gimple_asm_ninputs (asm_stmt));
 122         streamer_write_uhwi (ob, gimple_asm_noutputs (asm_stmt));
 123         streamer_write_uhwi (ob, gimple_asm_nclobbers (asm_stmt));
 124         streamer_write_uhwi (ob, gimple_asm_nlabels (asm_stmt));
 125         streamer_write_string (ob, ob->main_stream,
 126                                gimple_asm_string (asm_stmt), true);
 127       }
 128       /* Fallthru  */
 129
 130     case GIMPLE_ASSIGN:
 131     case GIMPLE_CALL:
 132     case GIMPLE_RETURN:
 133     case GIMPLE_SWITCH:
 134     case GIMPLE_LABEL:
 135     case GIMPLE_COND:
 136     case GIMPLE_GOTO:
 137     case GIMPLE_DEBUG:
 138       for (i = 0; i < gimple_num_ops (stmt); i++)
 139         {
 140           tree op = gimple_op (stmt, i);
 141           tree *basep = NULL;
 142           /* Wrap all uses of non-automatic variables inside MEM_REFs
 143              so that we do not have to deal with type mismatches on
 144              merged symbols during IL read in.  The first operand
 145              of GIMPLE_DEBUG must be a decl, not MEM_REF, though.  */
 146           if (op && (i || !is_gimple_debug (stmt)))
 147             {
 148               basep = &op;
 149               if (TREE_CODE (*basep) == ADDR_EXPR)
 150                 basep = &TREE_OPERAND (*basep, 0);
 151               while (handled_component_p (*basep))
 152                 basep = &TREE_OPERAND (*basep, 0);
 153               if (TREE_CODE (*basep) == VAR_DECL
 154                   && !auto_var_in_fn_p (*basep, current_function_decl)
 155                   && !DECL_REGISTER (*basep))
 156                 {
 157                   bool volatilep = TREE_THIS_VOLATILE (*basep);
 158                   tree ptrtype = build_pointer_type (TREE_TYPE (*basep));
 159                   *basep = build2 (MEM_REF, TREE_TYPE (*basep),
 160                                    build1 (ADDR_EXPR, ptrtype, *basep),
 161                                    build_int_cst (ptrtype, 0));
 162                   TREE_THIS_VOLATILE (*basep) = volatilep;
 163                 }
 164               else
 165                 basep = NULL;
 166             }
 167           stream_write_tree (ob, op, true);
 168           /* Restore the original base if we wrapped it inside a MEM_REF.  */
 169           if (basep)
 170             *basep = TREE_OPERAND (TREE_OPERAND (*basep, 0), 0);
 171         }
 172       if (is_gimple_call (stmt))
 173         {
 174           if (gimple_call_internal_p (stmt))
 175             streamer_write_enum (ob->main_stream, internal_fn,
 176                                  IFN_LAST, gimple_call_internal_fn (stmt));
 177           else
 178             stream_write_tree (ob, gimple_call_fntype (stmt), true);
 179         }
 180       break;
 181
 182     case GIMPLE_NOP:
 183     case GIMPLE_PREDICT:
 184       break;
 185
 186     case GIMPLE_TRANSACTION:
 187       {
 188         gtransaction *trans_stmt = as_a <gtransaction *> (stmt);
 189         gcc_assert (gimple_transaction_body (trans_stmt) == NULL);
 190         stream_write_tree (ob, gimple_transaction_label (trans_stmt), true);
 191       }
 192       break;
 193
 194     default:
 195       gcc_unreachable ();
 196     }
 197   if (hist)
 198     stream_out_histogram_value (ob, hist);
 199 }
 200
 201
 202 /* Output a basic block BB to the main stream in OB for this FN.  */
 203
 204 void
 205 output_bb (struct output_block *ob, basic_block bb, struct function *fn)
 206 {
 207   gimple_stmt_iterator bsi = gsi_start_bb (bb);
 208
 209   streamer_write_record_start (ob,
 210                                (!gsi_end_p (bsi)) || phi_nodes (bb)
 211                                 ? LTO_bb1
 212                                 : LTO_bb0);
 213
 214   streamer_write_uhwi (ob, bb->index);
 215   streamer_write_gcov_count (ob, bb->count);
 216   streamer_write_hwi (ob, bb->frequency);
 217   streamer_write_hwi (ob, bb->flags);
 218
 219   if (!gsi_end_p (bsi) || phi_nodes (bb))
 220     {
 221       /* Output the statements.  The list of statements is terminated
 222          with a zero.  */
 223       for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi))
 224         {
 225           int region;
 226           gimple stmt = gsi_stmt (bsi);
 227
 228           output_gimple_stmt (ob, stmt);
 229
 230           /* Emit the EH region holding STMT.  */
 231           region = lookup_stmt_eh_lp_fn (fn, stmt);
 232           if (region != 0)
 233             {
 234               streamer_write_record_start (ob, LTO_eh_region);
 235               streamer_write_hwi (ob, region);
 236             }
 237           else
 238             streamer_write_record_start (ob, LTO_null);
 239         }
 240
 241       streamer_write_record_start (ob, LTO_null);
 242
 243       for (gphi_iterator psi = gsi_start_phis (bb);
 244            !gsi_end_p (psi);
 245            gsi_next (&psi))
 246         {
 247           gphi *phi = psi.phi ();
 248
 249           /* Only emit PHIs for gimple registers.  PHI nodes for .MEM
 250              will be filled in on reading when the SSA form is
 251              updated.  */
 252           if (!virtual_operand_p (gimple_phi_result (phi)))
 253             output_phi (ob, phi);
 254         }
 255
 256       streamer_write_record_start (ob, LTO_null);
 257     }
 258 }