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 "machmode.h"
  28 #include "vec.h"
  29 #include "double-int.h"
  30 #include "input.h"
  31 #include "alias.h"
  32 #include "symtab.h"
  33 #include "options.h"
  34 #include "wide-int.h"
  35 #include "inchash.h"
  36 #include "tree.h"
  37 #include "fold-const.h"
  38 #include "predict.h"
  39 #include "tm.h"
  40 #include "hard-reg-set.h"
  41 #include "input.h"
  42 #include "function.h"
  43 #include "basic-block.h"
  44 #include "tree-ssa-alias.h"
  45 #include "internal-fn.h"
  46 #include "gimple-expr.h"
  47 #include "is-a.h"
  48 #include "gimple.h"
  49 #include "hash-map.h"
  50 #include "plugin-api.h"
  51 #include "ipa-ref.h"
  52 #include "cgraph.h"
  53 #include "data-streamer.h"
  54
  55
  56 /* Adds a new block to output stream OBS.  */
  57
  58 void
  59 lto_append_block (struct lto_output_stream *obs)
  60 {
  61   struct lto_char_ptr_base *new_block;
  62
  63   gcc_assert (obs->left_in_block == 0);
  64
  65   if (obs->first_block == NULL)
  66     {
  67       /* This is the first time the stream has been written
  68          into.  */
  69       obs->block_size = 1024;
  70       new_block = (struct lto_char_ptr_base*) xmalloc (obs->block_size);
  71       obs->first_block = new_block;
  72     }
  73   else
  74     {
  75       struct lto_char_ptr_base *tptr;
  76       /* Get a new block that is twice as big as the last block
  77          and link it into the list.  */
  78       obs->block_size *= 2;
  79       new_block = (struct lto_char_ptr_base*) xmalloc (obs->block_size);
  80       /* The first bytes of the block are reserved as a pointer to
  81          the next block.  Set the chain of the full block to the
  82          pointer to the new block.  */
  83       tptr = obs->current_block;
  84       tptr->ptr = (char *) new_block;
  85     }
  86
  87   /* Set the place for the next char at the first position after the
  88      chain to the next block.  */
  89   obs->current_pointer
  90     = ((char *) new_block) + sizeof (struct lto_char_ptr_base);
  91   obs->current_block = new_block;
  92   /* Null out the newly allocated block's pointer to the next block.  */
  93   new_block->ptr = NULL;
  94   obs->left_in_block = obs->block_size - sizeof (struct lto_char_ptr_base);
  95 }
  96
  97
  98 /* Return index used to reference STRING of LEN characters in the string table
  99    in OB.  The string might or might not include a trailing '\0'.
 100    Then put the index onto the INDEX_STREAM.
 101    When PERSISTENT is set, the string S is supposed to not change during
 102    duration of the OB and thus OB can keep pointer into it.  */
 103
 104 static unsigned
 105 streamer_string_index (struct output_block *ob, const char *s, unsigned int len,
 106                        bool persistent)
 107 {
 108   struct string_slot **slot;
 109   struct string_slot s_slot;
 110
 111   s_slot.s = s;
 112   s_slot.len = len;
 113   s_slot.slot_num = 0;
 114
 115   slot = ob->string_hash_table->find_slot (&s_slot, INSERT);
 116   if (*slot == NULL)
 117     {
 118       struct lto_output_stream *string_stream = ob->string_stream;
 119       unsigned int start = string_stream->total_size;
 120       struct string_slot *new_slot = XOBNEW (&ob->obstack, struct string_slot);
 121       const char *string;
 122
 123       if (!persistent)
 124         {
 125           char *tmp;
 126           string = tmp = XOBNEWVEC (&ob->obstack, char, len);
 127           memcpy (tmp, s, len);
 128         }
 129       else
 130         string = s;
 131
 132       new_slot->s = string;
 133       new_slot->len = len;
 134       new_slot->slot_num = start;
 135       *slot = new_slot;
 136       streamer_write_uhwi_stream (string_stream, len);
 137       streamer_write_data_stream (string_stream, string, len);
 138       return start + 1;
 139     }
 140   else
 141     {
 142       struct string_slot *old_slot = *slot;
 143       return old_slot->slot_num + 1;
 144     }
 145 }
 146
 147
 148 /* Output STRING of LEN characters to the string table in OB. The
 149    string might or might not include a trailing '\0'. Then put the
 150    index onto the INDEX_STREAM.
 151    When PERSISTENT is set, the string S is supposed to not change during
 152    duration of the OB and thus OB can keep pointer into it.  */
 153
 154 void
 155 streamer_write_string_with_length (struct output_block *ob,
 156                                    struct lto_output_stream *index_stream,
 157                                    const char *s, unsigned int len,
 158                                    bool persistent)
 159 {
 160   if (s)
 161     streamer_write_uhwi_stream (index_stream,
 162                                 streamer_string_index (ob, s, len, persistent));
 163   else
 164     streamer_write_char_stream (index_stream, 0);
 165 }
 166
 167
 168 /* Output the '\0' terminated STRING to the string
 169    table in OB.  Then put the index onto the INDEX_STREAM.
 170    When PERSISTENT is set, the string S is supposed to not change during
 171    duration of the OB and thus OB can keep pointer into it.  */
 172
 173 void
 174 streamer_write_string (struct output_block *ob,
 175                        struct lto_output_stream *index_stream,
 176                        const char *string, bool persistent)
 177 {
 178   if (string)
 179     streamer_write_string_with_length (ob, index_stream, string,
 180                                        strlen (string) + 1,
 181                                        persistent);
 182   else
 183     streamer_write_char_stream (index_stream, 0);
 184 }
 185
 186
 187 /* Output STRING of LEN characters to the string table in OB.  Then
 188    put the index into BP.
 189    When PERSISTENT is set, the string S is supposed to not change during
 190    duration of the OB and thus OB can keep pointer into it.  */
 191
 192 void
 193 bp_pack_string_with_length (struct output_block *ob, struct bitpack_d *bp,
 194                             const char *s, unsigned int len, bool persistent)
 195 {
 196   unsigned index = 0;
 197   if (s)
 198     index = streamer_string_index (ob, s, len, persistent);
 199   bp_pack_var_len_unsigned (bp, index);
 200 }
 201
 202
 203 /* Output the '\0' terminated STRING to the string
 204    table in OB.  Then put the index onto the bitpack BP.
 205    When PERSISTENT is set, the string S is supposed to not change during
 206    duration of the OB and thus OB can keep pointer into it.  */
 207
 208 void
 209 bp_pack_string (struct output_block *ob, struct bitpack_d *bp,
 210                 const char *s, bool persistent)
 211 {
 212   unsigned index = 0;
 213   if (s)
 214     index = streamer_string_index (ob, s, strlen (s) + 1, persistent);
 215   bp_pack_var_len_unsigned (bp, index);
 216 }
 217
 218
 219
 220 /* Write a zero to the output stream.  */
 221
 222 void
 223 streamer_write_zero (struct output_block *ob)
 224 {
 225   streamer_write_char_stream (ob->main_stream, 0);
 226 }
 227
 228
 229 /* Write an unsigned HOST_WIDE_INT value WORK to OB->main_stream.  */
 230
 231 void
 232 streamer_write_uhwi (struct output_block *ob, unsigned HOST_WIDE_INT work)
 233 {
 234   streamer_write_uhwi_stream (ob->main_stream, work);
 235 }
 236
 237
 238 /* Write a HOST_WIDE_INT value WORK to OB->main_stream.  */
 239
 240 void
 241 streamer_write_hwi (struct output_block *ob, HOST_WIDE_INT work)
 242 {
 243   streamer_write_hwi_stream (ob->main_stream, work);
 244 }
 245
 246 /* Write a gcov counter value WORK to OB->main_stream.  */
 247
 248 void
 249 streamer_write_gcov_count (struct output_block *ob, gcov_type work)
 250 {
 251   streamer_write_gcov_count_stream (ob->main_stream, work);
 252 }
 253
 254 /* Write an unsigned HOST_WIDE_INT value WORK to OBS.  */
 255
 256 void
 257 streamer_write_uhwi_stream (struct lto_output_stream *obs,
 258                             unsigned HOST_WIDE_INT work)
 259 {
 260   if (obs->left_in_block == 0)
 261     lto_append_block (obs);
 262   char *current_pointer = obs->current_pointer;
 263   unsigned int left_in_block = obs->left_in_block;
 264   unsigned int size = 0;
 265   do
 266     {
 267       unsigned int byte = (work & 0x7f);
 268       work >>= 7;
 269       if (work != 0)
 270         /* More bytes to follow.  */
 271         byte |= 0x80;
 272
 273       *(current_pointer++) = byte;
 274       left_in_block--;
 275       size++;
 276     }
 277   while (work != 0 && left_in_block > 0);
 278   if (work != 0)
 279     {
 280       obs->left_in_block = 0;
 281       lto_append_block (obs);
 282       current_pointer = obs->current_pointer;
 283       left_in_block = obs->left_in_block;
 284       do
 285         {
 286           unsigned int byte = (work & 0x7f);
 287           work >>= 7;
 288           if (work != 0)
 289             /* More bytes to follow.  */
 290             byte |= 0x80;
 291
 292           *(current_pointer++) = byte;
 293           left_in_block--;
 294           size++;
 295         }
 296       while (work != 0);
 297     }
 298   obs->current_pointer = current_pointer;
 299   obs->left_in_block = left_in_block;
 300   obs->total_size += size;
 301 }
 302
 303
 304 /* Write a HOST_WIDE_INT value WORK to OBS.  */
 305
 306 void
 307 streamer_write_hwi_stream (struct lto_output_stream *obs, HOST_WIDE_INT work)
 308 {
 309   if (obs->left_in_block == 0)
 310     lto_append_block (obs);
 311   char *current_pointer = obs->current_pointer;
 312   unsigned int left_in_block = obs->left_in_block;
 313   unsigned int size = 0;
 314   bool more;
 315   do
 316     {
 317       unsigned int byte = (work & 0x7f);
 318       /* If the lower 7-bits are sign-extended 0 or -1 we are finished.  */
 319       work >>= 6;
 320       more = !(work == 0 || work == -1);
 321       if (more)
 322         {
 323           /* More bits to follow.  */
 324           work >>= 1;
 325           byte |= 0x80;
 326         }
 327
 328       *(current_pointer++) = byte;
 329       left_in_block--;
 330       size++;
 331     }
 332   while (more && left_in_block > 0);
 333   if (more)
 334     {
 335       obs->left_in_block = 0;
 336       lto_append_block (obs);
 337       current_pointer = obs->current_pointer;
 338       left_in_block = obs->left_in_block;
 339       do
 340         {
 341           unsigned int byte = (work & 0x7f);
 342           work >>= 6;
 343           more = !(work == 0 || work == -1);
 344           if (more)
 345             {
 346               work >>= 1;
 347               byte |= 0x80;
 348             }
 349
 350           *(current_pointer++) = byte;
 351           left_in_block--;
 352           size++;
 353         }
 354       while (more);
 355     }
 356   obs->current_pointer = current_pointer;
 357   obs->left_in_block = left_in_block;
 358   obs->total_size += size;
 359 }
 360
 361 /* Write a GCOV counter value WORK to OBS.  */
 362
 363 void
 364 streamer_write_gcov_count_stream (struct lto_output_stream *obs, gcov_type work)
 365 {
 366   gcc_assert (work >= 0);
 367   gcc_assert ((HOST_WIDE_INT) work == work);
 368   streamer_write_hwi_stream (obs, work);
 369 }
 370
 371 /* Write raw DATA of length LEN to the output block OB.  */
 372
 373 void
 374 streamer_write_data_stream (struct lto_output_stream *obs, const void *data,
 375                             size_t len)
 376 {
 377   while (len)
 378     {
 379       size_t copy;
 380
 381       /* No space left.  */
 382       if (obs->left_in_block == 0)
 383         lto_append_block (obs);
 384
 385       /* Determine how many bytes to copy in this loop.  */
 386       if (len <= obs->left_in_block)
 387         copy = len;
 388       else
 389         copy = obs->left_in_block;
 390
 391       /* Copy the data and do bookkeeping.  */
 392       memcpy (obs->current_pointer, data, copy);
 393       obs->current_pointer += copy;
 394       obs->total_size += copy;
 395       obs->left_in_block -= copy;
 396       data = (const char *) data + copy;
 397       len -= copy;
 398     }
 399 }
 400