gcc/data-streamer.c

   1 /* Generic streaming support for basic data types.
   2
   3    Copyright (C) 2011-2015 Free Software Foundation, Inc.
   4    Contributed by Diego Novillo <dnovillo@google.com>
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 3, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22 #include "config.h"
  23 #include "system.h"
  24 #include "coretypes.h"
  25 #include "alias.h"
  26 #include "symtab.h"
  27 #include "options.h"
  28 #include "tree.h"
  29 #include "fold-const.h"
  30 #include "predict.h"
  31 #include "tm.h"
  32 #include "hard-reg-set.h"
  33 #include "function.h"
  34 #include "basic-block.h"
  35 #include "tree-ssa-alias.h"
  36 #include "internal-fn.h"
  37 #include "gimple-expr.h"
  38 #include "gimple.h"
  39 #include "plugin-api.h"
  40 #include "ipa-ref.h"
  41 #include "cgraph.h"
  42 #include "data-streamer.h"
  43
  44 /* Pack WORK into BP in a variant of uleb format.  */
  45
  46 void
  47 bp_pack_var_len_unsigned (struct bitpack_d *bp, unsigned HOST_WIDE_INT work)
  48 {
  49   do
  50     {
  51       unsigned int half_byte = (work & 0x7);
  52       work >>= 3;
  53       if (work != 0)
  54         /* More half_bytes to follow.  */
  55         half_byte |= 0x8;
  56
  57       bp_pack_value (bp, half_byte, 4);
  58     }
  59   while (work != 0);
  60 }
  61
  62
  63 /* Pack WORK into BP in a variant of sleb format.  */
  64
  65 void
  66 bp_pack_var_len_int (struct bitpack_d *bp, HOST_WIDE_INT work)
  67 {
  68   int more, half_byte;
  69
  70   do
  71     {
  72       half_byte = (work & 0x7);
  73       /* arithmetic shift */
  74       work >>= 3;
  75       more = !((work == 0 && (half_byte & 0x4) == 0)
  76                || (work == -1 && (half_byte & 0x4) != 0));
  77       if (more)
  78         half_byte |= 0x8;
  79
  80       bp_pack_value (bp, half_byte, 4);
  81     }
  82   while (more);
  83 }
  84
  85
  86 /* Unpack VAL from BP in a variant of uleb format.  */
  87
  88 unsigned HOST_WIDE_INT
  89 bp_unpack_var_len_unsigned (struct bitpack_d *bp)
  90 {
  91   unsigned HOST_WIDE_INT result = 0;
  92   int shift = 0;
  93   unsigned HOST_WIDE_INT half_byte;
  94
  95   while (true)
  96     {
  97       half_byte = bp_unpack_value (bp, 4);
  98       result |= (half_byte & 0x7) << shift;
  99       shift += 3;
 100       if ((half_byte & 0x8) == 0)
 101         return result;
 102     }
 103 }
 104
 105
 106 /* Unpack VAL from BP in a variant of sleb format.  */
 107
 108 HOST_WIDE_INT
 109 bp_unpack_var_len_int (struct bitpack_d *bp)
 110 {
 111   HOST_WIDE_INT result = 0;
 112   int shift = 0;
 113   unsigned HOST_WIDE_INT half_byte;
 114
 115   while (true)
 116     {
 117       half_byte = bp_unpack_value (bp, 4);
 118       result |= (half_byte & 0x7) << shift;
 119       shift += 3;
 120       if ((half_byte & 0x8) == 0)
 121         {
 122           if ((shift < HOST_BITS_PER_WIDE_INT) && (half_byte & 0x4))
 123             result |= - (HOST_WIDE_INT_1U << shift);
 124
 125           return result;
 126         }
 127     }
 128 }