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) 2011-2013 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 "gimple.h"
  28 #include "data-streamer.h"
  29
  30 /* Return index used to reference STRING of LEN characters in the string table
  31    in OB.  The string might or might not include a trailing '\0'.
  32    Then put the index onto the INDEX_STREAM.
  33    When PERSISTENT is set, the string S is supposed to not change during
  34    duration of the OB and thus OB can keep pointer into it.  */
  35
  36 unsigned
  37 streamer_string_index (struct output_block *ob, const char *s, unsigned int len,
  38                        bool persistent)
  39 {
  40   struct string_slot **slot;
  41   struct string_slot s_slot;
  42
  43   s_slot.s = s;
  44   s_slot.len = len;
  45   s_slot.slot_num = 0;
  46
  47   slot = ob->string_hash_table.find_slot (&s_slot, INSERT);
  48   if (*slot == NULL)
  49     {
  50       struct lto_output_stream *string_stream = ob->string_stream;
  51       unsigned int start = string_stream->total_size;
  52       struct string_slot *new_slot = XOBNEW (&ob->obstack, struct string_slot);
  53       const char *string;
  54
  55       if (!persistent)
  56         {
  57           char *tmp;
  58           string = tmp = XOBNEWVEC (&ob->obstack, char, len);
  59           memcpy (tmp, s, len);
  60         }
  61       else
  62         string = s;
  63
  64       new_slot->s = string;
  65       new_slot->len = len;
  66       new_slot->slot_num = start;
  67       *slot = new_slot;
  68       streamer_write_uhwi_stream (string_stream, len);
  69       lto_output_data_stream (string_stream, string, len);
  70       return start + 1;
  71     }
  72   else
  73     {
  74       struct string_slot *old_slot = *slot;
  75       return old_slot->slot_num + 1;
  76     }
  77 }
  78
  79
  80 /* Output STRING of LEN characters to the string table in OB. The
  81    string might or might not include a trailing '\0'. Then put the
  82    index onto the INDEX_STREAM.
  83    When PERSISTENT is set, the string S is supposed to not change during
  84    duration of the OB and thus OB can keep pointer into it.  */
  85
  86 void
  87 streamer_write_string_with_length (struct output_block *ob,
  88                                    struct lto_output_stream *index_stream,
  89                                    const char *s, unsigned int len,
  90                                    bool persistent)
  91 {
  92   if (s)
  93     streamer_write_uhwi_stream (index_stream,
  94                                 streamer_string_index (ob, s, len, persistent));
  95   else
  96     streamer_write_char_stream (index_stream, 0);
  97 }
  98
  99
 100 /* Output the '\0' terminated STRING to the string
 101    table in OB.  Then put the index onto the INDEX_STREAM.
 102    When PERSISTENT is set, the string S is supposed to not change during
 103    duration of the OB and thus OB can keep pointer into it.  */
 104
 105 void
 106 streamer_write_string (struct output_block *ob,
 107                        struct lto_output_stream *index_stream,
 108                        const char *string, bool persistent)
 109 {
 110   if (string)
 111     streamer_write_string_with_length (ob, index_stream, string,
 112                                        strlen (string) + 1,
 113                                        persistent);
 114   else
 115     streamer_write_char_stream (index_stream, 0);
 116 }
 117
 118
 119 /* Output STRING of LEN characters to the string table in OB.  Then
 120    put the index into BP.
 121    When PERSISTENT is set, the string S is supposed to not change during
 122    duration of the OB and thus OB can keep pointer into it.  */
 123
 124 void
 125 bp_pack_string_with_length (struct output_block *ob, struct bitpack_d *bp,
 126                             const char *s, unsigned int len, bool persistent)
 127 {
 128   unsigned index = 0;
 129   if (s)
 130     index = streamer_string_index (ob, s, len, persistent);
 131   bp_pack_var_len_unsigned (bp, index);
 132 }
 133
 134
 135 /* Output the '\0' terminated STRING to the string
 136    table in OB.  Then put the index onto the bitpack BP.
 137    When PERSISTENT is set, the string S is supposed to not change during
 138    duration of the OB and thus OB can keep pointer into it.  */
 139
 140 void
 141 bp_pack_string (struct output_block *ob, struct bitpack_d *bp,
 142                 const char *s, bool persistent)
 143 {
 144   unsigned index = 0;
 145   if (s)
 146     index = streamer_string_index (ob, s, strlen (s) + 1, persistent);
 147   bp_pack_var_len_unsigned (bp, index);
 148 }
 149
 150
 151
 152 /* Write a zero to the output stream.  */
 153
 154 void
 155 streamer_write_zero (struct output_block *ob)
 156 {
 157   streamer_write_char_stream (ob->main_stream, 0);
 158 }
 159
 160
 161 /* Write an unsigned HOST_WIDE_INT value WORK to OB->main_stream.  */
 162
 163 void
 164 streamer_write_uhwi (struct output_block *ob, unsigned HOST_WIDE_INT work)
 165 {
 166   streamer_write_uhwi_stream (ob->main_stream, work);
 167 }
 168
 169
 170 /* Write a HOST_WIDE_INT value WORK to OB->main_stream.  */
 171
 172 void
 173 streamer_write_hwi (struct output_block *ob, HOST_WIDE_INT work)
 174 {
 175   streamer_write_hwi_stream (ob->main_stream, work);
 176 }
 177
 178 /* Write a gcov counter value WORK to OB->main_stream.  */
 179
 180 void
 181 streamer_write_gcov_count (struct output_block *ob, gcov_type work)
 182 {
 183   streamer_write_gcov_count_stream (ob->main_stream, work);
 184 }
 185
 186 /* Write an unsigned HOST_WIDE_INT value WORK to OBS.  */
 187
 188 void
 189 streamer_write_uhwi_stream (struct lto_output_stream *obs,
 190                             unsigned HOST_WIDE_INT work)
 191 {
 192   if (obs->left_in_block == 0)
 193     lto_append_block (obs);
 194   char *current_pointer = obs->current_pointer;
 195   unsigned int left_in_block = obs->left_in_block;
 196   unsigned int size = 0;
 197   do
 198     {
 199       unsigned int byte = (work & 0x7f);
 200       work >>= 7;
 201       if (work != 0)
 202         /* More bytes to follow.  */
 203         byte |= 0x80;
 204
 205       *(current_pointer++) = byte;
 206       left_in_block--;
 207       size++;
 208     }
 209   while (work != 0 && left_in_block > 0);
 210   if (work != 0)
 211     {
 212       obs->left_in_block = 0;
 213       lto_append_block (obs);
 214       current_pointer = obs->current_pointer;
 215       left_in_block = obs->left_in_block;
 216       do
 217         {
 218           unsigned int byte = (work & 0x7f);
 219           work >>= 7;
 220           if (work != 0)
 221             /* More bytes to follow.  */
 222             byte |= 0x80;
 223
 224           *(current_pointer++) = byte;
 225           left_in_block--;
 226           size++;
 227         }
 228       while (work != 0);
 229     }
 230   obs->current_pointer = current_pointer;
 231   obs->left_in_block = left_in_block;
 232   obs->total_size += size;
 233 }
 234
 235
 236 /* Write a HOST_WIDE_INT value WORK to OBS.  */
 237
 238 void
 239 streamer_write_hwi_stream (struct lto_output_stream *obs, HOST_WIDE_INT work)
 240 {
 241   if (obs->left_in_block == 0)
 242     lto_append_block (obs);
 243   char *current_pointer = obs->current_pointer;
 244   unsigned int left_in_block = obs->left_in_block;
 245   unsigned int size = 0;
 246   bool more;
 247   do
 248     {
 249       unsigned int byte = (work & 0x7f);
 250       /* If the lower 7-bits are sign-extended 0 or -1 we are finished.  */
 251       work >>= 6;
 252       more = !(work == 0 || work == -1);
 253       if (more)
 254         {
 255           /* More bits to follow.  */
 256           work >>= 1;
 257           byte |= 0x80;
 258         }
 259
 260       *(current_pointer++) = byte;
 261       left_in_block--;
 262       size++;
 263     }
 264   while (more && left_in_block > 0);
 265   if (more)
 266     {
 267       obs->left_in_block = 0;
 268       lto_append_block (obs);
 269       current_pointer = obs->current_pointer;
 270       left_in_block = obs->left_in_block;
 271       do
 272         {
 273           unsigned int byte = (work & 0x7f);
 274           work >>= 6;
 275           more = !(work == 0 || work == -1);
 276           if (more)
 277             {
 278               work >>= 1;
 279               byte |= 0x80;
 280             }
 281
 282           *(current_pointer++) = byte;
 283           left_in_block--;
 284           size++;
 285         }
 286       while (more);
 287     }
 288   obs->current_pointer = current_pointer;
 289   obs->left_in_block = left_in_block;
 290   obs->total_size += size;
 291 }
 292
 293 /* Write a GCOV counter value WORK to OBS.  */
 294
 295 void
 296 streamer_write_gcov_count_stream (struct lto_output_stream *obs, gcov_type work)
 297 {
 298   gcc_assert (work >= 0);
 299   gcc_assert ((HOST_WIDE_INT) work == work);
 300   streamer_write_hwi_stream (obs, work);
 301 }