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) 2011-2014 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 "tree.h"
  27 #include "basic-block.h"
  28 #include "tree-ssa-alias.h"
  29 #include "internal-fn.h"
  30 #include "gimple-expr.h"
  31 #include "is-a.h"
  32 #include "gimple.h"
  33 #include "data-streamer.h"
  34
  35
  36 /* Adds a new block to output stream OBS.  */
  37
  38 void
  39 lto_append_block (struct lto_output_stream *obs)
  40 {
  41   struct lto_char_ptr_base *new_block;
  42
  43   gcc_assert (obs->left_in_block == 0);
  44
  45   if (obs->first_block == NULL)
  46     {
  47       /* This is the first time the stream has been written
  48          into.  */
  49       obs->block_size = 1024;
  50       new_block = (struct lto_char_ptr_base*) xmalloc (obs->block_size);
  51       obs->first_block = new_block;
  52     }
  53   else
  54     {
  55       struct lto_char_ptr_base *tptr;
  56       /* Get a new block that is twice as big as the last block
  57          and link it into the list.  */
  58       obs->block_size *= 2;
  59       new_block = (struct lto_char_ptr_base*) xmalloc (obs->block_size);
  60       /* The first bytes of the block are reserved as a pointer to
  61          the next block.  Set the chain of the full block to the
  62          pointer to the new block.  */
  63       tptr = obs->current_block;
  64       tptr->ptr = (char *) new_block;
  65     }
  66
  67   /* Set the place for the next char at the first position after the
  68      chain to the next block.  */
  69   obs->current_pointer
  70     = ((char *) new_block) + sizeof (struct lto_char_ptr_base);
  71   obs->current_block = new_block;
  72   /* Null out the newly allocated block's pointer to the next block.  */
  73   new_block->ptr = NULL;
  74   obs->left_in_block = obs->block_size - sizeof (struct lto_char_ptr_base);
  75 }
  76
  77
  78 /* Return index used to reference STRING of LEN characters in the string table
  79    in OB.  The string might or might not include a trailing '\0'.
  80    Then put the index onto the INDEX_STREAM.
  81    When PERSISTENT is set, the string S is supposed to not change during
  82    duration of the OB and thus OB can keep pointer into it.  */
  83
  84 static unsigned
  85 streamer_string_index (struct output_block *ob, const char *s, unsigned int len,
  86                        bool persistent)
  87 {
  88   struct string_slot **slot;
  89   struct string_slot s_slot;
  90
  91   s_slot.s = s;
  92   s_slot.len = len;
  93   s_slot.slot_num = 0;
  94
  95   slot = ob->string_hash_table->find_slot (&s_slot, INSERT);
  96   if (*slot == NULL)
  97     {
  98       struct lto_output_stream *string_stream = ob->string_stream;
  99       unsigned int start = string_stream->total_size;
 100       struct string_slot *new_slot = XOBNEW (&ob->obstack, struct string_slot);
 101       const char *string;
 102
 103       if (!persistent)
 104         {
 105           char *tmp;
 106           string = tmp = XOBNEWVEC (&ob->obstack, char, len);
 107           memcpy (tmp, s, len);
 108         }
 109       else
 110         string = s;
 111
 112       new_slot->s = string;
 113       new_slot->len = len;
 114       new_slot->slot_num = start;
 115       *slot = new_slot;
 116       streamer_write_uhwi_stream (string_stream, len);
 117       streamer_write_data_stream (string_stream, string, len);
 118       return start + 1;
 119     }
 120   else
 121     {
 122       struct string_slot *old_slot = *slot;
 123       return old_slot->slot_num + 1;
 124     }
 125 }
 126
 127
 128 /* Output STRING of LEN characters to the string table in OB. The
 129    string might or might not include a trailing '\0'. Then put the
 130    index onto the INDEX_STREAM.
 131    When PERSISTENT is set, the string S is supposed to not change during
 132    duration of the OB and thus OB can keep pointer into it.  */
 133
 134 void
 135 streamer_write_string_with_length (struct output_block *ob,
 136                                    struct lto_output_stream *index_stream,
 137                                    const char *s, unsigned int len,
 138                                    bool persistent)
 139 {
 140   if (s)
 141     streamer_write_uhwi_stream (index_stream,
 142                                 streamer_string_index (ob, s, len, persistent));
 143   else
 144     streamer_write_char_stream (index_stream, 0);
 145 }
 146
 147
 148 /* Output the '\0' terminated STRING to the string
 149    table in OB.  Then put the index onto the INDEX_STREAM.
 150    When PERSISTENT is set, the string S is supposed to not change during
 151    duration of the OB and thus OB can keep pointer into it.  */
 152
 153 void
 154 streamer_write_string (struct output_block *ob,
 155                        struct lto_output_stream *index_stream,
 156                        const char *string, bool persistent)
 157 {
 158   if (string)
 159     streamer_write_string_with_length (ob, index_stream, string,
 160                                        strlen (string) + 1,
 161                                        persistent);
 162   else
 163     streamer_write_char_stream (index_stream, 0);
 164 }
 165
 166
 167 /* Output STRING of LEN characters to the string table in OB.  Then
 168    put the index into BP.
 169    When PERSISTENT is set, the string S is supposed to not change during
 170    duration of the OB and thus OB can keep pointer into it.  */
 171
 172 void
 173 bp_pack_string_with_length (struct output_block *ob, struct bitpack_d *bp,
 174                             const char *s, unsigned int len, bool persistent)
 175 {
 176   unsigned index = 0;
 177   if (s)
 178     index = streamer_string_index (ob, s, len, persistent);
 179   bp_pack_var_len_unsigned (bp, index);
 180 }
 181
 182
 183 /* Output the '\0' terminated STRING to the string
 184    table in OB.  Then put the index onto the bitpack BP.
 185    When PERSISTENT is set, the string S is supposed to not change during
 186    duration of the OB and thus OB can keep pointer into it.  */
 187
 188 void
 189 bp_pack_string (struct output_block *ob, struct bitpack_d *bp,
 190                 const char *s, bool persistent)
 191 {
 192   unsigned index = 0;
 193   if (s)
 194     index = streamer_string_index (ob, s, strlen (s) + 1, persistent);
 195   bp_pack_var_len_unsigned (bp, index);
 196 }
 197
 198
 199
 200 /* Write a zero to the output stream.  */
 201
 202 void
 203 streamer_write_zero (struct output_block *ob)
 204 {
 205   streamer_write_char_stream (ob->main_stream, 0);
 206 }
 207
 208
 209 /* Write an unsigned HOST_WIDE_INT value WORK to OB->main_stream.  */
 210
 211 void
 212 streamer_write_uhwi (struct output_block *ob, unsigned HOST_WIDE_INT work)
 213 {
 214   streamer_write_uhwi_stream (ob->main_stream, work);
 215 }
 216
 217
 218 /* Write a HOST_WIDE_INT value WORK to OB->main_stream.  */
 219
 220 void
 221 streamer_write_hwi (struct output_block *ob, HOST_WIDE_INT work)
 222 {
 223   streamer_write_hwi_stream (ob->main_stream, work);
 224 }
 225
 226 /* Write a gcov counter value WORK to OB->main_stream.  */
 227
 228 void
 229 streamer_write_gcov_count (struct output_block *ob, gcov_type work)
 230 {
 231   streamer_write_gcov_count_stream (ob->main_stream, work);
 232 }
 233
 234 /* Write an unsigned HOST_WIDE_INT value WORK to OBS.  */
 235
 236 void
 237 streamer_write_uhwi_stream (struct lto_output_stream *obs,
 238                             unsigned HOST_WIDE_INT work)
 239 {
 240   if (obs->left_in_block == 0)
 241     lto_append_block (obs);
 242   char *current_pointer = obs->current_pointer;
 243   unsigned int left_in_block = obs->left_in_block;
 244   unsigned int size = 0;
 245   do
 246     {
 247       unsigned int byte = (work & 0x7f);
 248       work >>= 7;
 249       if (work != 0)
 250         /* More bytes to follow.  */
 251         byte |= 0x80;
 252
 253       *(current_pointer++) = byte;
 254       left_in_block--;
 255       size++;
 256     }
 257   while (work != 0 && left_in_block > 0);
 258   if (work != 0)
 259     {
 260       obs->left_in_block = 0;
 261       lto_append_block (obs);
 262       current_pointer = obs->current_pointer;
 263       left_in_block = obs->left_in_block;
 264       do
 265         {
 266           unsigned int byte = (work & 0x7f);
 267           work >>= 7;
 268           if (work != 0)
 269             /* More bytes to follow.  */
 270             byte |= 0x80;
 271
 272           *(current_pointer++) = byte;
 273           left_in_block--;
 274           size++;
 275         }
 276       while (work != 0);
 277     }
 278   obs->current_pointer = current_pointer;
 279   obs->left_in_block = left_in_block;
 280   obs->total_size += size;
 281 }
 282
 283
 284 /* Write a HOST_WIDE_INT value WORK to OBS.  */
 285
 286 void
 287 streamer_write_hwi_stream (struct lto_output_stream *obs, HOST_WIDE_INT work)
 288 {
 289   if (obs->left_in_block == 0)
 290     lto_append_block (obs);
 291   char *current_pointer = obs->current_pointer;
 292   unsigned int left_in_block = obs->left_in_block;
 293   unsigned int size = 0;
 294   bool more;
 295   do
 296     {
 297       unsigned int byte = (work & 0x7f);
 298       /* If the lower 7-bits are sign-extended 0 or -1 we are finished.  */
 299       work >>= 6;
 300       more = !(work == 0 || work == -1);
 301       if (more)
 302         {
 303           /* More bits to follow.  */
 304           work >>= 1;
 305           byte |= 0x80;
 306         }
 307
 308       *(current_pointer++) = byte;
 309       left_in_block--;
 310       size++;
 311     }
 312   while (more && left_in_block > 0);
 313   if (more)
 314     {
 315       obs->left_in_block = 0;
 316       lto_append_block (obs);
 317       current_pointer = obs->current_pointer;
 318       left_in_block = obs->left_in_block;
 319       do
 320         {
 321           unsigned int byte = (work & 0x7f);
 322           work >>= 6;
 323           more = !(work == 0 || work == -1);
 324           if (more)
 325             {
 326               work >>= 1;
 327               byte |= 0x80;
 328             }
 329
 330           *(current_pointer++) = byte;
 331           left_in_block--;
 332           size++;
 333         }
 334       while (more);
 335     }
 336   obs->current_pointer = current_pointer;
 337   obs->left_in_block = left_in_block;
 338   obs->total_size += size;
 339 }
 340
 341 /* Write a GCOV counter value WORK to OBS.  */
 342
 343 void
 344 streamer_write_gcov_count_stream (struct lto_output_stream *obs, gcov_type work)
 345 {
 346   gcc_assert (work >= 0);
 347   gcc_assert ((HOST_WIDE_INT) work == work);
 348   streamer_write_hwi_stream (obs, work);
 349 }
 350
 351 /* Write raw DATA of length LEN to the output block OB.  */
 352
 353 void
 354 streamer_write_data_stream (struct lto_output_stream *obs, const void *data,
 355                             size_t len)
 356 {
 357   while (len)
 358     {
 359       size_t copy;
 360
 361       /* No space left.  */
 362       if (obs->left_in_block == 0)
 363         lto_append_block (obs);
 364
 365       /* Determine how many bytes to copy in this loop.  */
 366       if (len <= obs->left_in_block)
 367         copy = len;
 368       else
 369         copy = obs->left_in_block;
 370
 371       /* Copy the data and do bookkeeping.  */
 372       memcpy (obs->current_pointer, data, copy);
 373       obs->current_pointer += copy;
 374       obs->total_size += copy;
 375       obs->left_in_block -= copy;
 376       data = (const char *) data + copy;
 377       len -= copy;
 378     }
 379 }
 380