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