gcc/gimple-streamer-out.c

   1 /* Routines for emitting GIMPLE to a file stream.
   2
   3    Copyright (C) 2011-2017 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 "backend.h"
  26 #include "tree.h"
  27 #include "gimple.h"
  28 #include "gimple-ssa.h"
  29 #include "gimple-streamer.h"
  30 #include "tree-eh.h"
  31 #include "gimple-iterator.h"
  32 #include "cgraph.h"
  33 #include "value-prof.h"
  34
  35 /* Output PHI function PHI to the main stream in OB.  */
  36
  37 static void
  38 output_phi (struct output_block *ob, gphi *phi)
  39 {
  40   unsigned i, len = gimple_phi_num_args (phi);
  41
  42   streamer_write_record_start (ob, lto_gimple_code_to_tag (GIMPLE_PHI));
  43   streamer_write_uhwi (ob, SSA_NAME_VERSION (PHI_RESULT (phi)));
  44
  45   for (i = 0; i < len; i++)
  46     {
  47       stream_write_tree (ob, gimple_phi_arg_def (phi, i), true);
  48       streamer_write_uhwi (ob, gimple_phi_arg_edge (phi, i)->src->index);
  49       bitpack_d bp = bitpack_create (ob->main_stream);
  50       stream_output_location (ob, &bp, gimple_phi_arg_location (phi, i));
  51       streamer_write_bitpack (&bp);
  52     }
  53 }
  54
  55
  56 /* Emit statement STMT on the main stream of output block OB.  */
  57
  58 static void
  59 output_gimple_stmt (struct output_block *ob, gimple *stmt)
  60 {
  61   unsigned i;
  62   enum gimple_code code;
  63   enum LTO_tags tag;
  64   struct bitpack_d bp;
  65   histogram_value hist;
  66
  67   /* Emit identifying tag.  */
  68   code = gimple_code (stmt);
  69   tag = lto_gimple_code_to_tag (code);
  70   streamer_write_record_start (ob, tag);
  71
  72   /* Emit the tuple header.  */
  73   bp = bitpack_create (ob->main_stream);
  74   bp_pack_var_len_unsigned (&bp, gimple_num_ops (stmt));
  75   bp_pack_value (&bp, gimple_no_warning_p (stmt), 1);
  76   if (is_gimple_assign (stmt))
  77     bp_pack_value (&bp,
  78                    gimple_assign_nontemporal_move_p (
  79                      as_a <gassign *> (stmt)),
  80                    1);
  81   bp_pack_value (&bp, gimple_has_volatile_ops (stmt), 1);
  82   hist = gimple_histogram_value (cfun, stmt);
  83   bp_pack_value (&bp, hist != NULL, 1);
  84   bp_pack_var_len_unsigned (&bp, stmt->subcode);
  85
  86   /* Emit location information for the statement.  */
  87   stream_output_location (ob, &bp, LOCATION_LOCUS (gimple_location (stmt)));
  88   streamer_write_bitpack (&bp);
  89
  90   /* Emit the lexical block holding STMT.  */
  91   stream_write_tree (ob, gimple_block (stmt), true);
  92
  93   /* Emit the operands.  */
  94   switch (gimple_code (stmt))
  95     {
  96     case GIMPLE_RESX:
  97       streamer_write_hwi (ob, gimple_resx_region (as_a <gresx *> (stmt)));
  98       break;
  99
 100     case GIMPLE_EH_MUST_NOT_THROW:
 101       stream_write_tree (ob,
 102                          gimple_eh_must_not_throw_fndecl (
 103                            as_a <geh_mnt *> (stmt)),
 104                          true);
 105       break;
 106
 107     case GIMPLE_EH_DISPATCH:
 108       streamer_write_hwi (ob,
 109                           gimple_eh_dispatch_region (
 110                             as_a <geh_dispatch *> (stmt)));
 111       break;
 112
 113     case GIMPLE_ASM:
 114       {
 115         gasm *asm_stmt = as_a <gasm *> (stmt);
 116         streamer_write_uhwi (ob, gimple_asm_ninputs (asm_stmt));
 117         streamer_write_uhwi (ob, gimple_asm_noutputs (asm_stmt));
 118         streamer_write_uhwi (ob, gimple_asm_nclobbers (asm_stmt));
 119         streamer_write_uhwi (ob, gimple_asm_nlabels (asm_stmt));
 120         streamer_write_string (ob, ob->main_stream,
 121                                gimple_asm_string (asm_stmt), true);
 122       }
 123       /* Fallthru  */
 124
 125     case GIMPLE_ASSIGN:
 126     case GIMPLE_CALL:
 127     case GIMPLE_RETURN:
 128     case GIMPLE_SWITCH:
 129     case GIMPLE_LABEL:
 130     case GIMPLE_COND:
 131     case GIMPLE_GOTO:
 132     case GIMPLE_DEBUG:
 133       for (i = 0; i < gimple_num_ops (stmt); i++)
 134         {
 135           tree op = gimple_op (stmt, i);
 136           tree *basep = NULL;
 137           /* Wrap all uses of non-automatic variables inside MEM_REFs
 138              so that we do not have to deal with type mismatches on
 139              merged symbols during IL read in.  The first operand
 140              of GIMPLE_DEBUG must be a decl, not MEM_REF, though.  */
 141           if (op && (i || !is_gimple_debug (stmt)))
 142             {
 143               basep = &op;
 144               if (TREE_CODE (*basep) == ADDR_EXPR)
 145                 basep = &TREE_OPERAND (*basep, 0);
 146               while (handled_component_p (*basep))
 147                 basep = &TREE_OPERAND (*basep, 0);
 148               if (VAR_P (*basep)
 149                   && !auto_var_in_fn_p (*basep, current_function_decl)
 150                   && !DECL_REGISTER (*basep))
 151                 {
 152                   bool volatilep = TREE_THIS_VOLATILE (*basep);
 153                   tree ptrtype = build_pointer_type (TREE_TYPE (*basep));
 154                   *basep = build2 (MEM_REF, TREE_TYPE (*basep),
 155                                    build1 (ADDR_EXPR, ptrtype, *basep),
 156                                    build_int_cst (ptrtype, 0));
 157                   TREE_THIS_VOLATILE (*basep) = volatilep;
 158                 }
 159               else
 160                 basep = NULL;
 161             }
 162           stream_write_tree (ob, op, true);
 163           /* Restore the original base if we wrapped it inside a MEM_REF.  */
 164           if (basep)
 165             *basep = TREE_OPERAND (TREE_OPERAND (*basep, 0), 0);
 166         }
 167       if (is_gimple_call (stmt))
 168         {
 169           if (gimple_call_internal_p (stmt))
 170             streamer_write_enum (ob->main_stream, internal_fn,
 171                                  IFN_LAST, gimple_call_internal_fn (stmt));
 172           else
 173             stream_write_tree (ob, gimple_call_fntype (stmt), true);
 174         }
 175       break;
 176
 177     case GIMPLE_NOP:
 178     case GIMPLE_PREDICT:
 179       break;
 180
 181     case GIMPLE_TRANSACTION:
 182       {
 183         gtransaction *txn = as_a <gtransaction *> (stmt);
 184         gcc_assert (gimple_transaction_body (txn) == NULL);
 185         stream_write_tree (ob, gimple_transaction_label_norm (txn), true);
 186         stream_write_tree (ob, gimple_transaction_label_uninst (txn), true);
 187         stream_write_tree (ob, gimple_transaction_label_over (txn), true);
 188       }
 189       break;
 190
 191     default:
 192       gcc_unreachable ();
 193     }
 194   if (hist)
 195     stream_out_histogram_value (ob, hist);
 196 }
 197
 198
 199 /* Output a basic block BB to the main stream in OB for this FN.  */
 200
 201 void
 202 output_bb (struct output_block *ob, basic_block bb, struct function *fn)
 203 {
 204   gimple_stmt_iterator bsi = gsi_start_bb (bb);
 205
 206   streamer_write_record_start (ob,
 207                                (!gsi_end_p (bsi)) || phi_nodes (bb)
 208                                 ? LTO_bb1
 209                                 : LTO_bb0);
 210
 211   streamer_write_uhwi (ob, bb->index);
 212   bb->count.stream_out (ob);
 213   streamer_write_hwi (ob, bb->flags);
 214
 215   if (!gsi_end_p (bsi) || phi_nodes (bb))
 216     {
 217       /* Output the statements.  The list of statements is terminated
 218          with a zero.  */
 219       for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi))
 220         {
 221           int region;
 222           gimple *stmt = gsi_stmt (bsi);
 223
 224           output_gimple_stmt (ob, stmt);
 225
 226           /* Emit the EH region holding STMT.  */
 227           region = lookup_stmt_eh_lp_fn (fn, stmt);
 228           if (region != 0)
 229             {
 230               streamer_write_record_start (ob, LTO_eh_region);
 231               streamer_write_hwi (ob, region);
 232             }
 233           else
 234             streamer_write_record_start (ob, LTO_null);
 235         }
 236
 237       streamer_write_record_start (ob, LTO_null);
 238
 239       for (gphi_iterator psi = gsi_start_phis (bb);
 240            !gsi_end_p (psi);
 241            gsi_next (&psi))
 242         {
 243           gphi *phi = psi.phi ();
 244
 245           /* Only emit PHIs for gimple registers.  PHI nodes for .MEM
 246              will be filled in on reading when the SSA form is
 247              updated.  */
 248           if (!virtual_operand_p (gimple_phi_result (phi)))
 249             output_phi (ob, phi);
 250         }
 251
 252       streamer_write_record_start (ob, LTO_null);
 253     }
 254 }