gcc/lto-streamer.c

   1 /* Miscellaneous utilities for GIMPLE streaming.  Things that are used
   2    in both input and output are here.
   3
   4    Copyright (C) 2009-2018 Free Software Foundation, Inc.
   5    Contributed by Doug Kwan <dougkwan@google.com>
   6
   7 This file is part of GCC.
   8
   9 GCC is free software; you can redistribute it and/or modify it under
  10 the terms of the GNU General Public License as published by the Free
  11 Software Foundation; either version 3, or (at your option) any later
  12 version.
  13
  14 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  15 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  16 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  17 for more details.
  18
  19 You should have received a copy of the GNU General Public License
  20 along with GCC; see the file COPYING3.  If not see
  21 <http://www.gnu.org/licenses/>.  */
  22
  23 #include "config.h"
  24 #include "system.h"
  25 #include "coretypes.h"
  26 #include "backend.h"
  27 #include "tree.h"
  28 #include "gimple.h"
  29 #include "tree-streamer.h"
  30 #include "cgraph.h"
  31 #include "lto-streamer.h"
  32 #include "toplev.h"
  33 #include "lto-section-names.h"
  34
  35 /* Statistics gathered during LTO, WPA and LTRANS.  */
  36 struct lto_stats_d lto_stats;
  37
  38 /* LTO uses bitmaps with different life-times.  So use a separate
  39    obstack for all LTO bitmaps.  */
  40 static bitmap_obstack lto_obstack;
  41 static bool lto_obstack_initialized;
  42
  43 const char *section_name_prefix = LTO_SECTION_NAME_PREFIX;
  44 /* Set when streaming LTO for offloading compiler.  */
  45 bool lto_stream_offload_p;
  46
  47 FILE *streamer_dump_file;
  48
  49 /* Return a string representing LTO tag TAG.  */
  50
  51 const char *
  52 lto_tag_name (enum LTO_tags tag)
  53 {
  54   if (lto_tag_is_tree_code_p (tag))
  55     {
  56       /* For tags representing tree nodes, return the name of the
  57          associated tree code.  */
  58       return get_tree_code_name (lto_tag_to_tree_code (tag));
  59     }
  60
  61   if (lto_tag_is_gimple_code_p (tag))
  62     {
  63       /* For tags representing gimple statements, return the name of
  64          the associated gimple code.  */
  65       return gimple_code_name[lto_tag_to_gimple_code (tag)];
  66     }
  67
  68   switch (tag)
  69     {
  70     case LTO_null:
  71       return "LTO_null";
  72     case LTO_bb0:
  73       return "LTO_bb0";
  74     case LTO_bb1:
  75       return "LTO_bb1";
  76     case LTO_eh_region:
  77       return "LTO_eh_region";
  78     case LTO_function:
  79       return "LTO_function";
  80     case LTO_eh_table:
  81       return "LTO_eh_table";
  82     case LTO_ert_cleanup:
  83       return "LTO_ert_cleanup";
  84     case LTO_ert_try:
  85       return "LTO_ert_try";
  86     case LTO_ert_allowed_exceptions:
  87       return "LTO_ert_allowed_exceptions";
  88     case LTO_ert_must_not_throw:
  89       return "LTO_ert_must_not_throw";
  90     case LTO_tree_pickle_reference:
  91       return "LTO_tree_pickle_reference";
  92     case LTO_field_decl_ref:
  93       return "LTO_field_decl_ref";
  94     case LTO_function_decl_ref:
  95       return "LTO_function_decl_ref";
  96     case LTO_label_decl_ref:
  97       return "LTO_label_decl_ref";
  98     case LTO_namespace_decl_ref:
  99       return "LTO_namespace_decl_ref";
 100     case LTO_result_decl_ref:
 101       return "LTO_result_decl_ref";
 102     case LTO_ssa_name_ref:
 103       return "LTO_ssa_name_ref";
 104     case LTO_type_decl_ref:
 105       return "LTO_type_decl_ref";
 106     case LTO_type_ref:
 107       return "LTO_type_ref";
 108     case LTO_global_decl_ref:
 109       return "LTO_global_decl_ref";
 110     default:
 111       return "LTO_UNKNOWN";
 112     }
 113 }
 114
 115
 116 /* Allocate a bitmap from heap.  Initializes the LTO obstack if necessary.  */
 117
 118 bitmap
 119 lto_bitmap_alloc (void)
 120 {
 121   if (!lto_obstack_initialized)
 122     {
 123       bitmap_obstack_initialize (&lto_obstack);
 124       lto_obstack_initialized = true;
 125     }
 126   return BITMAP_ALLOC (&lto_obstack);
 127 }
 128
 129 /* Free bitmap B.  */
 130
 131 void
 132 lto_bitmap_free (bitmap b)
 133 {
 134   BITMAP_FREE (b);
 135 }
 136
 137
 138 /* Get a section name for a particular type or name.  The NAME field
 139    is only used if SECTION_TYPE is LTO_section_function_body. For all
 140    others it is ignored.  The callee of this function is responsible
 141    to free the returned name.  */
 142
 143 char *
 144 lto_get_section_name (int section_type, const char *name, struct lto_file_decl_data *f)
 145 {
 146   const char *add;
 147   char post[32];
 148   const char *sep;
 149
 150   if (section_type == LTO_section_function_body)
 151     {
 152       gcc_assert (name != NULL);
 153       if (name[0] == '*')
 154         name++;
 155       add = name;
 156       sep = "";
 157     }
 158   else if (section_type < LTO_N_SECTION_TYPES)
 159     {
 160       add = lto_section_name[section_type];
 161       sep = ".";
 162     }
 163   else
 164     internal_error ("bytecode stream: unexpected LTO section %s", name);
 165
 166   /* Make the section name unique so that ld -r combining sections
 167      doesn't confuse the reader with merged sections.
 168
 169      For options don't add a ID, the option reader cannot deal with them
 170      and merging should be ok here. */
 171   if (section_type == LTO_section_opts)
 172     strcpy (post, "");
 173   else if (f != NULL)
 174     sprintf (post, "." HOST_WIDE_INT_PRINT_HEX_PURE, f->id);
 175   else
 176     sprintf (post, "." HOST_WIDE_INT_PRINT_HEX_PURE, get_random_seed (false));
 177   return concat (section_name_prefix, sep, add, post, NULL);
 178 }
 179
 180
 181 /* Show various memory usage statistics related to LTO.  */
 182
 183 void
 184 print_lto_report (const char *s)
 185 {
 186   unsigned i;
 187
 188   fprintf (stderr, "[%s] # of input files: "
 189            HOST_WIDE_INT_PRINT_UNSIGNED "\n", s, lto_stats.num_input_files);
 190
 191   fprintf (stderr, "[%s] # of input cgraph nodes: "
 192            HOST_WIDE_INT_PRINT_UNSIGNED "\n", s,
 193            lto_stats.num_input_cgraph_nodes);
 194
 195   fprintf (stderr, "[%s] # of function bodies: "
 196            HOST_WIDE_INT_PRINT_UNSIGNED "\n", s,
 197            lto_stats.num_function_bodies);
 198
 199   for (i = 0; i < NUM_TREE_CODES; i++)
 200     if (lto_stats.num_trees[i])
 201       fprintf (stderr, "[%s] # of '%s' objects read: "
 202                HOST_WIDE_INT_PRINT_UNSIGNED "\n", s,
 203                get_tree_code_name ((enum tree_code) i), lto_stats.num_trees[i]);
 204
 205   if (flag_lto)
 206     {
 207       fprintf (stderr, "[%s] Compression: "
 208                HOST_WIDE_INT_PRINT_UNSIGNED " output bytes, "
 209                HOST_WIDE_INT_PRINT_UNSIGNED " compressed bytes", s,
 210                lto_stats.num_output_il_bytes,
 211                lto_stats.num_compressed_il_bytes);
 212       if (lto_stats.num_output_il_bytes > 0)
 213         {
 214           const float dividend = (float) lto_stats.num_compressed_il_bytes;
 215           const float divisor = (float) lto_stats.num_output_il_bytes;
 216           fprintf (stderr, " (ratio: %f)", dividend / divisor);
 217         }
 218       fprintf (stderr, "\n");
 219     }
 220
 221   if (flag_wpa)
 222     {
 223       fprintf (stderr, "[%s] # of output files: "
 224                HOST_WIDE_INT_PRINT_UNSIGNED "\n", s,
 225                lto_stats.num_output_files);
 226
 227       fprintf (stderr, "[%s] # of output symtab nodes: "
 228                HOST_WIDE_INT_PRINT_UNSIGNED "\n", s,
 229                lto_stats.num_output_symtab_nodes);
 230
 231       fprintf (stderr, "[%s] # of output tree pickle references: "
 232                HOST_WIDE_INT_PRINT_UNSIGNED "\n", s,
 233                lto_stats.num_pickle_refs_output);
 234       fprintf (stderr, "[%s] # of output tree bodies: "
 235                HOST_WIDE_INT_PRINT_UNSIGNED "\n", s,
 236                lto_stats.num_tree_bodies_output);
 237
 238       fprintf (stderr, "[%s] # callgraph partitions: "
 239                HOST_WIDE_INT_PRINT_UNSIGNED "\n", s,
 240                lto_stats.num_cgraph_partitions);
 241
 242       fprintf (stderr, "[%s] Compression: "
 243                HOST_WIDE_INT_PRINT_UNSIGNED " input bytes, "
 244                HOST_WIDE_INT_PRINT_UNSIGNED " uncompressed bytes", s,
 245                lto_stats.num_input_il_bytes,
 246                lto_stats.num_uncompressed_il_bytes);
 247       if (lto_stats.num_input_il_bytes > 0)
 248         {
 249           const float dividend = (float) lto_stats.num_uncompressed_il_bytes;
 250           const float divisor = (float) lto_stats.num_input_il_bytes;
 251           fprintf (stderr, " (ratio: %f)", dividend / divisor);
 252         }
 253       fprintf (stderr, "\n");
 254     }
 255
 256   for (i = 0; i < LTO_N_SECTION_TYPES; i++)
 257     fprintf (stderr, "[%s] Size of mmap'd section %s: "
 258              HOST_WIDE_INT_PRINT_UNSIGNED " bytes\n", s,
 259              lto_section_name[i], lto_stats.section_size[i]);
 260 }
 261
 262 /* Initialization common to the LTO reader and writer.  */
 263
 264 void
 265 lto_streamer_init (void)
 266 {
 267   /* Check that all the TS_* handled by the reader and writer routines
 268      match exactly the structures defined in treestruct.def.  When a
 269      new TS_* astructure is added, the streamer should be updated to
 270      handle it.  */
 271   if (flag_checking)
 272     streamer_check_handled_ts_structures ();
 273 }
 274
 275
 276 /* Gate function for all LTO streaming passes.  */
 277
 278 bool
 279 gate_lto_out (void)
 280 {
 281   return ((flag_generate_lto || flag_generate_offload || in_lto_p)
 282           /* Don't bother doing anything if the program has errors.  */
 283           && !seen_error ());
 284 }
 285
 286 /* Check that the version MAJOR.MINOR is the correct version number.  */
 287
 288 void
 289 lto_check_version (int major, int minor, const char *file_name)
 290 {
 291   if (major != LTO_major_version || minor != LTO_minor_version)
 292     fatal_error (input_location,
 293                  "bytecode stream in file %qs generated with LTO version "
 294                  "%d.%d instead of the expected %d.%d",
 295                  file_name,
 296                  major, minor,
 297                  LTO_major_version, LTO_minor_version);
 298 }
 299
 300
 301 /* Initialize all the streamer hooks used for streaming GIMPLE.  */
 302
 303 void
 304 lto_streamer_hooks_init (void)
 305 {
 306   streamer_hooks_init ();
 307   streamer_hooks.write_tree = lto_output_tree;
 308   streamer_hooks.read_tree = lto_input_tree;
 309   streamer_hooks.input_location = lto_input_location;
 310   streamer_hooks.output_location = lto_output_location;
 311 }