gcc/data-streamer-out.cc

   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) 2011-2023 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 "backend.h"
  27 #include "tree.h"
  28 #include "gimple.h"
  29 #include "cgraph.h"
  30 #include "data-streamer.h"
  31 #include "value-range.h"
  32 #include "streamer-hooks.h"
  33
  34
  35 /* Adds a new block to output stream OBS.  */
  36
  37 void
  38 lto_append_block (struct lto_output_stream *obs)
  39 {
  40   struct lto_char_ptr_base *new_block;
  41
  42   gcc_assert (obs->left_in_block == 0);
  43
  44   if (obs->first_block == NULL)
  45     {
  46       /* This is the first time the stream has been written
  47          into.  */
  48       obs->block_size = 1024;
  49       new_block = (struct lto_char_ptr_base*) xmalloc (obs->block_size);
  50       obs->first_block = new_block;
  51     }
  52   else
  53     {
  54       struct lto_char_ptr_base *tptr;
  55       /* Get a new block that is twice as big as the last block
  56          and link it into the list.  */
  57       obs->block_size *= 2;
  58       new_block = (struct lto_char_ptr_base*) xmalloc (obs->block_size);
  59       /* The first bytes of the block are reserved as a pointer to
  60          the next block.  Set the chain of the full block to the
  61          pointer to the new block.  */
  62       tptr = obs->current_block;
  63       tptr->ptr = (char *) new_block;
  64     }
  65
  66   /* Set the place for the next char at the first position after the
  67      chain to the next block.  */
  68   obs->current_pointer
  69     = ((char *) new_block) + sizeof (struct lto_char_ptr_base);
  70   obs->current_block = new_block;
  71   /* Null out the newly allocated block's pointer to the next block.  */
  72   new_block->ptr = NULL;
  73   obs->left_in_block = obs->block_size - sizeof (struct lto_char_ptr_base);
  74 }
  75
  76
  77 /* Return index used to reference STRING of LEN characters in the string table
  78    in OB.  The string might or might not include a trailing '\0'.
  79    Then put the index onto the INDEX_STREAM.
  80    When PERSISTENT is set, the string S is supposed to not change during
  81    duration of the OB and thus OB can keep pointer into it.  */
  82
  83 static unsigned
  84 streamer_string_index (struct output_block *ob, const char *s, unsigned int len,
  85                        bool persistent)
  86 {
  87   struct string_slot **slot;
  88   struct string_slot s_slot;
  89
  90   s_slot.s = s;
  91   s_slot.len = len;
  92   s_slot.slot_num = 0;
  93
  94   slot = ob->string_hash_table->find_slot (&s_slot, INSERT);
  95   if (*slot == NULL)
  96     {
  97       struct lto_output_stream *string_stream = ob->string_stream;
  98       unsigned int start = string_stream->total_size;
  99       struct string_slot *new_slot = XOBNEW (&ob->obstack, struct string_slot);
 100       const char *string;
 101
 102       if (!persistent)
 103         {
 104           char *tmp;
 105           string = tmp = XOBNEWVEC (&ob->obstack, char, len);
 106           memcpy (tmp, s, len);
 107         }
 108       else
 109         string = s;
 110
 111       new_slot->s = string;
 112       new_slot->len = len;
 113       new_slot->slot_num = start;
 114       *slot = new_slot;
 115       streamer_write_uhwi_stream (string_stream, len);
 116       streamer_write_data_stream (string_stream, string, len);
 117       return start + 1;
 118     }
 119   else
 120     {
 121       struct string_slot *old_slot = *slot;
 122       return old_slot->slot_num + 1;
 123     }
 124 }
 125
 126
 127 /* Output STRING of LEN characters to the string table in OB. The
 128    string might or might not include a trailing '\0'. Then put the
 129    index onto the INDEX_STREAM.
 130    When PERSISTENT is set, the string S is supposed to not change during
 131    duration of the OB and thus OB can keep pointer into it.  */
 132
 133 void
 134 streamer_write_string_with_length (struct output_block *ob,
 135                                    struct lto_output_stream *index_stream,
 136                                    const char *s, unsigned int len,
 137                                    bool persistent)
 138 {
 139   if (s)
 140     streamer_write_uhwi_stream (index_stream,
 141                                 streamer_string_index (ob, s, len, persistent));
 142   else
 143     streamer_write_char_stream (index_stream, 0);
 144 }
 145
 146
 147 /* Output the '\0' terminated STRING to the string
 148    table in OB.  Then put the index onto the INDEX_STREAM.
 149    When PERSISTENT is set, the string S is supposed to not change during
 150    duration of the OB and thus OB can keep pointer into it.  */
 151
 152 void
 153 streamer_write_string (struct output_block *ob,
 154                        struct lto_output_stream *index_stream,
 155                        const char *string, bool persistent)
 156 {
 157   if (string)
 158     streamer_write_string_with_length (ob, index_stream, string,
 159                                        strlen (string) + 1,
 160                                        persistent);
 161   else
 162     streamer_write_char_stream (index_stream, 0);
 163 }
 164
 165
 166 /* Output STRING of LEN characters to the string table in OB.  Then
 167    put the index into BP.
 168    When PERSISTENT is set, the string S is supposed to not change during
 169    duration of the OB and thus OB can keep pointer into it.  */
 170
 171 void
 172 bp_pack_string_with_length (struct output_block *ob, struct bitpack_d *bp,
 173                             const char *s, unsigned int len, bool persistent)
 174 {
 175   unsigned index = 0;
 176   if (s)
 177     index = streamer_string_index (ob, s, len, persistent);
 178   bp_pack_var_len_unsigned (bp, index);
 179 }
 180
 181
 182 /* Output the '\0' terminated STRING to the string
 183    table in OB.  Then put the index onto the bitpack BP.
 184    When PERSISTENT is set, the string S is supposed to not change during
 185    duration of the OB and thus OB can keep pointer into it.  */
 186
 187 void
 188 bp_pack_string (struct output_block *ob, struct bitpack_d *bp,
 189                 const char *s, bool persistent)
 190 {
 191   unsigned index = 0;
 192   if (s)
 193     index = streamer_string_index (ob, s, strlen (s) + 1, persistent);
 194   bp_pack_var_len_unsigned (bp, index);
 195 }
 196
 197
 198
 199 /* Write a zero to the output stream.  */
 200
 201 void
 202 streamer_write_zero (struct output_block *ob)
 203 {
 204   streamer_write_char_stream (ob->main_stream, 0);
 205 }
 206
 207
 208 /* Write an unsigned HOST_WIDE_INT value WORK to OB->main_stream.  */
 209
 210 void
 211 streamer_write_uhwi (struct output_block *ob, unsigned HOST_WIDE_INT work)
 212 {
 213   streamer_write_uhwi_stream (ob->main_stream, work);
 214 }
 215
 216
 217 /* Write a HOST_WIDE_INT value WORK to OB->main_stream.  */
 218
 219 void
 220 streamer_write_hwi (struct output_block *ob, HOST_WIDE_INT work)
 221 {
 222   streamer_write_hwi_stream (ob->main_stream, work);
 223 }
 224
 225 /* Write a poly_uint64 value WORK to OB->main_stream.  */
 226
 227 void
 228 streamer_write_poly_uint64 (struct output_block *ob, poly_uint64 work)
 229 {
 230   for (int i = 0; i < NUM_POLY_INT_COEFFS; ++i)
 231     streamer_write_uhwi_stream (ob->main_stream, work.coeffs[i]);
 232 }
 233
 234 /* Write a poly_int64 value WORK to OB->main_stream.  */
 235
 236 void
 237 streamer_write_poly_int64 (struct output_block *ob, poly_int64 work)
 238 {
 239   for (int i = 0; i < NUM_POLY_INT_COEFFS; ++i)
 240     streamer_write_hwi_stream (ob->main_stream, work.coeffs[i]);
 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 ((HOST_WIDE_INT) work == work);
 364   streamer_write_hwi_stream (obs, work);
 365 }
 366
 367 /* Write raw DATA of length LEN to the output block OB.  */
 368
 369 void
 370 streamer_write_data_stream (struct lto_output_stream *obs, const void *data,
 371                             size_t len)
 372 {
 373   while (len)
 374     {
 375       size_t copy;
 376
 377       /* No space left.  */
 378       if (obs->left_in_block == 0)
 379         lto_append_block (obs);
 380
 381       /* Determine how many bytes to copy in this loop.  */
 382       if (len <= obs->left_in_block)
 383         copy = len;
 384       else
 385         copy = obs->left_in_block;
 386
 387       /* Copy the data and do bookkeeping.  */
 388       memcpy (obs->current_pointer, data, copy);
 389       obs->current_pointer += copy;
 390       obs->total_size += copy;
 391       obs->left_in_block -= copy;
 392       data = (const char *) data + copy;
 393       len -= copy;
 394     }
 395 }
 396
 397 /* Write REAL_VALUE_TYPE into OB.  */
 398
 399 void
 400 streamer_write_real_value (struct output_block *ob, const REAL_VALUE_TYPE *r)
 401 {
 402   bitpack_d bp = bitpack_create (ob->main_stream);
 403   bp_pack_real_value (&bp, r);
 404   streamer_write_bitpack (&bp);
 405 }
 406
 407 void
 408 streamer_write_vrange (struct output_block *ob, const vrange &v)
 409 {
 410   gcc_checking_assert (!v.undefined_p ());
 411
 412   // Write the common fields to all vranges.
 413   value_range_kind kind = v.m_kind;
 414   streamer_write_enum (ob->main_stream, value_range_kind, VR_LAST, kind);
 415   stream_write_tree (ob, v.type (), true);
 416
 417   if (is_a <irange> (v))
 418     {
 419       const irange &r = as_a <irange> (v);
 420       streamer_write_uhwi (ob, r.num_pairs ());
 421       for (unsigned i = 0; i < r.num_pairs (); ++i)
 422         {
 423           streamer_write_wide_int (ob, r.lower_bound (i));
 424           streamer_write_wide_int (ob, r.upper_bound (i));
 425         }
 426       // TODO: We could avoid streaming out the value if the mask is -1.
 427       irange_bitmask bm = r.get_bitmask ();
 428       streamer_write_wide_int (ob, bm.value ());
 429       streamer_write_wide_int (ob, bm.mask ());
 430       return;
 431     }
 432   if (is_a <frange> (v))
 433     {
 434       const frange &r = as_a <frange> (v);
 435
 436       // Stream out NAN bits.
 437       bitpack_d bp = bitpack_create (ob->main_stream);
 438       nan_state nan = r.get_nan_state ();
 439       bp_pack_value (&bp, nan.pos_p (), 1);
 440       bp_pack_value (&bp, nan.neg_p (), 1);
 441       streamer_write_bitpack (&bp);
 442
 443       // Stream out bounds.
 444       if (kind != VR_NAN)
 445         {
 446           REAL_VALUE_TYPE lb = r.lower_bound ();
 447           REAL_VALUE_TYPE ub = r.upper_bound ();
 448           streamer_write_real_value (ob, &lb);
 449           streamer_write_real_value (ob, &ub);
 450         }
 451       return;
 452     }
 453   gcc_unreachable ();
 454 }
 455
 456 /* Emit the physical representation of wide_int VAL to output block OB.  */
 457
 458 void
 459 streamer_write_wide_int (struct output_block *ob, const wide_int &val)
 460 {
 461   int len = val.get_len ();
 462
 463   streamer_write_uhwi (ob, val.get_precision ());
 464   streamer_write_uhwi (ob, len);
 465   for (int i = 0; i < len; i++)
 466     streamer_write_hwi (ob, val.elt (i));
 467 }
 468
 469 /* Emit the physical representation of widest_int W to output block OB.  */
 470
 471 void
 472 streamer_write_widest_int (struct output_block *ob,
 473                            const widest_int &w)
 474 {
 475   int len = w.get_len ();
 476
 477   streamer_write_uhwi (ob, w.get_precision ());
 478   streamer_write_uhwi (ob, len);
 479   for (int i = 0; i < len; i++)
 480     streamer_write_hwi (ob, w.elt (i));
 481 }
 482