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