gcc/data-streamer-out.c

   1 /* Routines for saving various data types to a file stream.  This deals
   2    with various data types like strings, integers, enums, etc.
   3
   4    Copyright (C) 2011-2015 Free Software Foundation, Inc.
   5    Contributed by Diego Novillo <dnovillo@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 "hash-set.h"
  27 #include "vec.h"
  28 #include "input.h"
  29 #include "alias.h"
  30 #include "symtab.h"
  31 #include "options.h"
  32 #include "inchash.h"
  33 #include "tree.h"
  34 #include "fold-const.h"
  35 #include "predict.h"
  36 #include "tm.h"
  37 #include "hard-reg-set.h"
  38 #include "input.h"
  39 #include "function.h"
  40 #include "basic-block.h"
  41 #include "tree-ssa-alias.h"
  42 #include "internal-fn.h"
  43 #include "gimple-expr.h"
  44 #include "is-a.h"
  45 #include "gimple.h"
  46 #include "hash-map.h"
  47 #include "plugin-api.h"
  48 #include "ipa-ref.h"
  49 #include "cgraph.h"
  50 #include "data-streamer.h"
  51
  52
  53 /* Adds a new block to output stream OBS.  */
  54
  55 void
  56 lto_append_block (struct lto_output_stream *obs)
  57 {
  58   struct lto_char_ptr_base *new_block;
  59
  60   gcc_assert (obs->left_in_block == 0);
  61
  62   if (obs->first_block == NULL)
  63     {
  64       /* This is the first time the stream has been written
  65          into.  */
  66       obs->block_size = 1024;
  67       new_block = (struct lto_char_ptr_base*) xmalloc (obs->block_size);
  68       obs->first_block = new_block;
  69     }
  70   else
  71     {
  72       struct lto_char_ptr_base *tptr;
  73       /* Get a new block that is twice as big as the last block
  74          and link it into the list.  */
  75       obs->block_size *= 2;
  76       new_block = (struct lto_char_ptr_base*) xmalloc (obs->block_size);
  77       /* The first bytes of the block are reserved as a pointer to
  78          the next block.  Set the chain of the full block to the
  79          pointer to the new block.  */
  80       tptr = obs->current_block;
  81       tptr->ptr = (char *) new_block;
  82     }
  83
  84   /* Set the place for the next char at the first position after the
  85      chain to the next block.  */
  86   obs->current_pointer
  87     = ((char *) new_block) + sizeof (struct lto_char_ptr_base);
  88   obs->current_block = new_block;
  89   /* Null out the newly allocated block's pointer to the next block.  */
  90   new_block->ptr = NULL;
  91   obs->left_in_block = obs->block_size - sizeof (struct lto_char_ptr_base);
  92 }
  93
  94
  95 /* Return index used to reference STRING of LEN characters in the string table
  96    in OB.  The string might or might not include a trailing '\0'.
  97    Then put the index onto the INDEX_STREAM.
  98    When PERSISTENT is set, the string S is supposed to not change during
  99    duration of the OB and thus OB can keep pointer into it.  */
 100
 101 static unsigned
 102 streamer_string_index (struct output_block *ob, const char *s, unsigned int len,
 103                        bool persistent)
 104 {
 105   struct string_slot **slot;
 106   struct string_slot s_slot;
 107
 108   s_slot.s = s;
 109   s_slot.len = len;
 110   s_slot.slot_num = 0;
 111
 112   slot = ob->string_hash_table->find_slot (&s_slot, INSERT);
 113   if (*slot == NULL)
 114     {
 115       struct lto_output_stream *string_stream = ob->string_stream;
 116       unsigned int start = string_stream->total_size;
 117       struct string_slot *new_slot = XOBNEW (&ob->obstack, struct string_slot);
 118       const char *string;
 119
 120       if (!persistent)
 121         {
 122           char *tmp;
 123           string = tmp = XOBNEWVEC (&ob->obstack, char, len);
 124           memcpy (tmp, s, len);
 125         }
 126       else
 127         string = s;
 128
 129       new_slot->s = string;
 130       new_slot->len = len;
 131       new_slot->slot_num = start;
 132       *slot = new_slot;
 133       streamer_write_uhwi_stream (string_stream, len);
 134       streamer_write_data_stream (string_stream, string, len);
 135       return start + 1;
 136     }
 137   else
 138     {
 139       struct string_slot *old_slot = *slot;
 140       return old_slot->slot_num + 1;
 141     }
 142 }
 143
 144
 145 /* Output STRING of LEN characters to the string table in OB. The
 146    string might or might not include a trailing '\0'. Then put the
 147    index onto the INDEX_STREAM.
 148    When PERSISTENT is set, the string S is supposed to not change during
 149    duration of the OB and thus OB can keep pointer into it.  */
 150
 151 void
 152 streamer_write_string_with_length (struct output_block *ob,
 153                                    struct lto_output_stream *index_stream,
 154                                    const char *s, unsigned int len,
 155                                    bool persistent)
 156 {
 157   if (s)
 158     streamer_write_uhwi_stream (index_stream,
 159                                 streamer_string_index (ob, s, len, persistent));
 160   else
 161     streamer_write_char_stream (index_stream, 0);
 162 }
 163
 164
 165 /* Output the '\0' terminated STRING to the string
 166    table in OB.  Then put the index onto the INDEX_STREAM.
 167    When PERSISTENT is set, the string S is supposed to not change during
 168    duration of the OB and thus OB can keep pointer into it.  */
 169
 170 void
 171 streamer_write_string (struct output_block *ob,
 172                        struct lto_output_stream *index_stream,
 173                        const char *string, bool persistent)
 174 {
 175   if (string)
 176     streamer_write_string_with_length (ob, index_stream, string,
 177                                        strlen (string) + 1,
 178                                        persistent);
 179   else
 180     streamer_write_char_stream (index_stream, 0);
 181 }
 182
 183
 184 /* Output STRING of LEN characters to the string table in OB.  Then
 185    put the index into BP.
 186    When PERSISTENT is set, the string S is supposed to not change during
 187    duration of the OB and thus OB can keep pointer into it.  */
 188
 189 void
 190 bp_pack_string_with_length (struct output_block *ob, struct bitpack_d *bp,
 191                             const char *s, unsigned int len, bool persistent)
 192 {
 193   unsigned index = 0;
 194   if (s)
 195     index = streamer_string_index (ob, s, len, persistent);
 196   bp_pack_var_len_unsigned (bp, index);
 197 }
 198
 199
 200 /* Output the '\0' terminated STRING to the string
 201    table in OB.  Then put the index onto the bitpack BP.
 202    When PERSISTENT is set, the string S is supposed to not change during
 203    duration of the OB and thus OB can keep pointer into it.  */
 204
 205 void
 206 bp_pack_string (struct output_block *ob, struct bitpack_d *bp,
 207                 const char *s, bool persistent)
 208 {
 209   unsigned index = 0;
 210   if (s)
 211     index = streamer_string_index (ob, s, strlen (s) + 1, persistent);
 212   bp_pack_var_len_unsigned (bp, index);
 213 }
 214
 215
 216
 217 /* Write a zero to the output stream.  */
 218
 219 void
 220 streamer_write_zero (struct output_block *ob)
 221 {
 222   streamer_write_char_stream (ob->main_stream, 0);
 223 }
 224
 225
 226 /* Write an unsigned HOST_WIDE_INT value WORK to OB->main_stream.  */
 227
 228 void
 229 streamer_write_uhwi (struct output_block *ob, unsigned HOST_WIDE_INT work)
 230 {
 231   streamer_write_uhwi_stream (ob->main_stream, work);
 232 }
 233
 234
 235 /* Write a HOST_WIDE_INT value WORK to OB->main_stream.  */
 236
 237 void
 238 streamer_write_hwi (struct output_block *ob, HOST_WIDE_INT work)
 239 {
 240   streamer_write_hwi_stream (ob->main_stream, work);
 241 }
 242
 243 /* Write a gcov counter value WORK to OB->main_stream.  */
 244
 245 void
 246 streamer_write_gcov_count (struct output_block *ob, gcov_type work)
 247 {
 248   streamer_write_gcov_count_stream (ob->main_stream, work);
 249 }
 250
 251 /* Write an unsigned HOST_WIDE_INT value WORK to OBS.  */
 252
 253 void
 254 streamer_write_uhwi_stream (struct lto_output_stream *obs,
 255                             unsigned HOST_WIDE_INT work)
 256 {
 257   if (obs->left_in_block == 0)
 258     lto_append_block (obs);
 259   char *current_pointer = obs->current_pointer;
 260   unsigned int left_in_block = obs->left_in_block;
 261   unsigned int size = 0;
 262   do
 263     {
 264       unsigned int byte = (work & 0x7f);
 265       work >>= 7;
 266       if (work != 0)
 267         /* More bytes to follow.  */
 268         byte |= 0x80;
 269
 270       *(current_pointer++) = byte;
 271       left_in_block--;
 272       size++;
 273     }
 274   while (work != 0 && left_in_block > 0);
 275   if (work != 0)
 276     {
 277       obs->left_in_block = 0;
 278       lto_append_block (obs);
 279       current_pointer = obs->current_pointer;
 280       left_in_block = obs->left_in_block;
 281       do
 282         {
 283           unsigned int byte = (work & 0x7f);
 284           work >>= 7;
 285           if (work != 0)
 286             /* More bytes to follow.  */
 287             byte |= 0x80;
 288
 289           *(current_pointer++) = byte;
 290           left_in_block--;
 291           size++;
 292         }
 293       while (work != 0);
 294     }
 295   obs->current_pointer = current_pointer;
 296   obs->left_in_block = left_in_block;
 297   obs->total_size += size;
 298 }
 299
 300
 301 /* Write a HOST_WIDE_INT value WORK to OBS.  */
 302
 303 void
 304 streamer_write_hwi_stream (struct lto_output_stream *obs, HOST_WIDE_INT work)
 305 {
 306   if (obs->left_in_block == 0)
 307     lto_append_block (obs);
 308   char *current_pointer = obs->current_pointer;
 309   unsigned int left_in_block = obs->left_in_block;
 310   unsigned int size = 0;
 311   bool more;
 312   do
 313     {
 314       unsigned int byte = (work & 0x7f);
 315       /* If the lower 7-bits are sign-extended 0 or -1 we are finished.  */
 316       work >>= 6;
 317       more = !(work == 0 || work == -1);
 318       if (more)
 319         {
 320           /* More bits to follow.  */
 321           work >>= 1;
 322           byte |= 0x80;
 323         }
 324
 325       *(current_pointer++) = byte;
 326       left_in_block--;
 327       size++;
 328     }
 329   while (more && left_in_block > 0);
 330   if (more)
 331     {
 332       obs->left_in_block = 0;
 333       lto_append_block (obs);
 334       current_pointer = obs->current_pointer;
 335       left_in_block = obs->left_in_block;
 336       do
 337         {
 338           unsigned int byte = (work & 0x7f);
 339           work >>= 6;
 340           more = !(work == 0 || work == -1);
 341           if (more)
 342             {
 343               work >>= 1;
 344               byte |= 0x80;
 345             }
 346
 347           *(current_pointer++) = byte;
 348           left_in_block--;
 349           size++;
 350         }
 351       while (more);
 352     }
 353   obs->current_pointer = current_pointer;
 354   obs->left_in_block = left_in_block;
 355   obs->total_size += size;
 356 }
 357
 358 /* Write a GCOV counter value WORK to OBS.  */
 359
 360 void
 361 streamer_write_gcov_count_stream (struct lto_output_stream *obs, gcov_type work)
 362 {
 363   gcc_assert (work >= 0);
 364   gcc_assert ((HOST_WIDE_INT) work == work);
 365   streamer_write_hwi_stream (obs, work);
 366 }
 367
 368 /* Write raw DATA of length LEN to the output block OB.  */
 369
 370 void
 371 streamer_write_data_stream (struct lto_output_stream *obs, const void *data,
 372                             size_t len)
 373 {
 374   while (len)
 375     {
 376       size_t copy;
 377
 378       /* No space left.  */
 379       if (obs->left_in_block == 0)
 380         lto_append_block (obs);
 381
 382       /* Determine how many bytes to copy in this loop.  */
 383       if (len <= obs->left_in_block)
 384         copy = len;
 385       else
 386         copy = obs->left_in_block;
 387
 388       /* Copy the data and do bookkeeping.  */
 389       memcpy (obs->current_pointer, data, copy);
 390       obs->current_pointer += copy;
 391       obs->total_size += copy;
 392       obs->left_in_block -= copy;
 393       data = (const char *) data + copy;
 394       len -= copy;
 395     }
 396 }
 397