gcc/gimple-streamer-out.c

   1 /* Routines for emitting GIMPLE to a file stream.
   2
   3    Copyright (C) 2011-2020 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 #include "gimple-pretty-print.h"
  35
  36 /* Output PHI function PHI to the main stream in OB.  */
  37
  38 static void
  39 output_phi (struct output_block *ob, gphi *phi)
  40 {
  41   unsigned i, len = gimple_phi_num_args (phi);
  42
  43   streamer_write_record_start (ob, lto_gimple_code_to_tag (GIMPLE_PHI));
  44   streamer_write_uhwi (ob, SSA_NAME_VERSION (PHI_RESULT (phi)));
  45
  46   for (i = 0; i < len; i++)
  47     {
  48       stream_write_tree (ob, gimple_phi_arg_def (phi, i), true);
  49       streamer_write_uhwi (ob, gimple_phi_arg_edge (phi, i)->src->index);
  50       bitpack_d bp = bitpack_create (ob->main_stream);
  51       stream_output_location (ob, &bp, gimple_phi_arg_location (phi, i));
  52       streamer_write_bitpack (&bp);
  53     }
  54 }
  55
  56
  57 /* Emit statement STMT on the main stream of output block OB.  */
  58
  59 static void
  60 output_gimple_stmt (struct output_block *ob, struct function *fn, gimple *stmt)
  61 {
  62   unsigned i;
  63   enum gimple_code code;
  64   enum LTO_tags tag;
  65   struct bitpack_d bp;
  66   histogram_value hist;
  67
  68   /* Emit identifying tag.  */
  69   code = gimple_code (stmt);
  70   tag = lto_gimple_code_to_tag (code);
  71   streamer_write_record_start (ob, tag);
  72
  73   /* Emit the tuple header.  */
  74   bp = bitpack_create (ob->main_stream);
  75   bp_pack_var_len_unsigned (&bp, gimple_num_ops (stmt));
  76   bp_pack_value (&bp, gimple_no_warning_p (stmt), 1);
  77   if (is_gimple_assign (stmt))
  78     bp_pack_value (&bp,
  79                    gimple_assign_nontemporal_move_p (
  80                      as_a <gassign *> (stmt)),
  81                    1);
  82   bp_pack_value (&bp, gimple_has_volatile_ops (stmt), 1);
  83   hist = gimple_histogram_value (fn, stmt);
  84   bp_pack_value (&bp, hist != NULL, 1);
  85   bp_pack_var_len_unsigned (&bp, stmt->subcode);
  86
  87   /* Emit location information for the statement.  */
  88   stream_output_location (ob, &bp, LOCATION_LOCUS (gimple_location (stmt)));
  89   streamer_write_bitpack (&bp);
  90
  91   /* Emit the lexical block holding STMT.  */
  92   stream_write_tree (ob, gimple_block (stmt), true);
  93
  94   /* Emit the operands.  */
  95   switch (gimple_code (stmt))
  96     {
  97     case GIMPLE_RESX:
  98       streamer_write_hwi (ob, gimple_resx_region (as_a <gresx *> (stmt)));
  99       break;
 100
 101     case GIMPLE_EH_MUST_NOT_THROW:
 102       stream_write_tree (ob,
 103                          gimple_eh_must_not_throw_fndecl (
 104                            as_a <geh_mnt *> (stmt)),
 105                          true);
 106       break;
 107
 108     case GIMPLE_EH_DISPATCH:
 109       streamer_write_hwi (ob,
 110                           gimple_eh_dispatch_region (
 111                             as_a <geh_dispatch *> (stmt)));
 112       break;
 113
 114     case GIMPLE_ASM:
 115       {
 116         gasm *asm_stmt = as_a <gasm *> (stmt);
 117         streamer_write_uhwi (ob, gimple_asm_ninputs (asm_stmt));
 118         streamer_write_uhwi (ob, gimple_asm_noutputs (asm_stmt));
 119         streamer_write_uhwi (ob, gimple_asm_nclobbers (asm_stmt));
 120         streamer_write_uhwi (ob, gimple_asm_nlabels (asm_stmt));
 121         streamer_write_string (ob, ob->main_stream,
 122                                gimple_asm_string (asm_stmt), true);
 123       }
 124       /* Fallthru  */
 125
 126     case GIMPLE_ASSIGN:
 127     case GIMPLE_CALL:
 128     case GIMPLE_RETURN:
 129     case GIMPLE_SWITCH:
 130     case GIMPLE_LABEL:
 131     case GIMPLE_COND:
 132     case GIMPLE_GOTO:
 133     case GIMPLE_DEBUG:
 134       for (i = 0; i < gimple_num_ops (stmt); i++)
 135         {
 136           tree op = gimple_op (stmt, i);
 137           tree *basep = NULL;
 138           /* Wrap all uses of non-automatic variables inside MEM_REFs
 139              so that we do not have to deal with type mismatches on
 140              merged symbols during IL read in.  The first operand
 141              of GIMPLE_DEBUG must be a decl, not MEM_REF, though.  */
 142           if (!flag_wpa && op && (i || !is_gimple_debug (stmt)))
 143             {
 144               basep = &op;
 145               if (TREE_CODE (*basep) == ADDR_EXPR)
 146                 basep = &TREE_OPERAND (*basep, 0);
 147               while (handled_component_p (*basep))
 148                 basep = &TREE_OPERAND (*basep, 0);
 149               if (VAR_P (*basep)
 150                   && !auto_var_in_fn_p (*basep, fn->decl)
 151                   && !DECL_REGISTER (*basep))
 152                 {
 153                   bool volatilep = TREE_THIS_VOLATILE (*basep);
 154                   tree ptrtype = build_pointer_type (TREE_TYPE (*basep));
 155                   *basep = build2 (MEM_REF, TREE_TYPE (*basep),
 156                                    build1 (ADDR_EXPR, ptrtype, *basep),
 157                                    build_int_cst (ptrtype, 0));
 158                   TREE_THIS_VOLATILE (*basep) = volatilep;
 159                 }
 160               else
 161                 basep = NULL;
 162             }
 163           stream_write_tree (ob, op, true);
 164           /* Restore the original base if we wrapped it inside a MEM_REF.  */
 165           if (basep)
 166             *basep = TREE_OPERAND (TREE_OPERAND (*basep, 0), 0);
 167         }
 168       if (is_gimple_call (stmt))
 169         {
 170           if (gimple_call_internal_p (stmt))
 171             streamer_write_enum (ob->main_stream, internal_fn,
 172                                  IFN_LAST, gimple_call_internal_fn (stmt));
 173           else
 174             stream_write_tree (ob, gimple_call_fntype (stmt), true);
 175         }
 176       break;
 177
 178     case GIMPLE_NOP:
 179     case GIMPLE_PREDICT:
 180       break;
 181
 182     case GIMPLE_TRANSACTION:
 183       {
 184         gtransaction *txn = as_a <gtransaction *> (stmt);
 185         gcc_assert (gimple_transaction_body (txn) == NULL);
 186         stream_write_tree (ob, gimple_transaction_label_norm (txn), true);
 187         stream_write_tree (ob, gimple_transaction_label_uninst (txn), true);
 188         stream_write_tree (ob, gimple_transaction_label_over (txn), true);
 189       }
 190       break;
 191
 192     default:
 193       gcc_unreachable ();
 194     }
 195   if (hist)
 196     stream_out_histogram_value (ob, hist);
 197 }
 198
 199
 200 /* Output a basic block BB to the main stream in OB for this FN.  */
 201
 202 void
 203 output_bb (struct output_block *ob, basic_block bb, struct function *fn)
 204 {
 205   gimple_stmt_iterator bsi = gsi_start_bb (bb);
 206
 207   streamer_write_record_start (ob,
 208                                (!gsi_end_p (bsi)) || phi_nodes (bb)
 209                                 ? LTO_bb1
 210                                 : LTO_bb0);
 211
 212   streamer_write_uhwi (ob, bb->index);
 213   bb->count.stream_out (ob);
 214   streamer_write_hwi (ob, bb->flags);
 215   streamer_write_hwi (ob, bb->discriminator);
 216
 217   if (!gsi_end_p (bsi) || phi_nodes (bb))
 218     {
 219       /* Output the statements.  The list of statements is terminated
 220          with a zero.  */
 221       for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi))
 222         {
 223           int region;
 224           gimple *stmt = gsi_stmt (bsi);
 225           if (streamer_dump_file)
 226             {
 227               fprintf (streamer_dump_file, "  Streaming gimple stmt ");
 228               print_gimple_stmt (streamer_dump_file, stmt, 0, TDF_SLIM);
 229             }
 230
 231           output_gimple_stmt (ob, fn, stmt);
 232
 233           /* Emit the EH region holding STMT.  */
 234           region = lookup_stmt_eh_lp_fn (fn, stmt);
 235           if (region != 0)
 236             {
 237               streamer_write_record_start (ob, LTO_eh_region);
 238               streamer_write_hwi (ob, region);
 239             }
 240           else
 241             streamer_write_record_start (ob, LTO_null);
 242         }
 243
 244       streamer_write_record_start (ob, LTO_null);
 245
 246       for (gphi_iterator psi = gsi_start_phis (bb);
 247            !gsi_end_p (psi);
 248            gsi_next (&psi))
 249         {
 250           gphi *phi = psi.phi ();
 251
 252           /* Only emit PHIs for gimple registers.  PHI nodes for .MEM
 253              will be filled in on reading when the SSA form is
 254              updated.  */
 255           if (!virtual_operand_p (gimple_phi_result (phi)))
 256             output_phi (ob, phi);
 257         }
 258
 259       streamer_write_record_start (ob, LTO_null);
 260     }
 261 }