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