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 "cgraph.h"
  40 #include "data-streamer.h"
  41
  42 /* Pack WORK into BP in a variant of uleb format.  */
  43
  44 void
  45 bp_pack_var_len_unsigned (struct bitpack_d *bp, unsigned HOST_WIDE_INT work)
  46 {
  47   do
  48     {
  49       unsigned int half_byte = (work & 0x7);
  50       work >>= 3;
  51       if (work != 0)
  52         /* More half_bytes to follow.  */
  53         half_byte |= 0x8;
  54
  55       bp_pack_value (bp, half_byte, 4);
  56     }
  57   while (work != 0);
  58 }
  59
  60
  61 /* Pack WORK into BP in a variant of sleb format.  */
  62
  63 void
  64 bp_pack_var_len_int (struct bitpack_d *bp, HOST_WIDE_INT work)
  65 {
  66   int more, half_byte;
  67
  68   do
  69     {
  70       half_byte = (work & 0x7);
  71       /* arithmetic shift */
  72       work >>= 3;
  73       more = !((work == 0 && (half_byte & 0x4) == 0)
  74                || (work == -1 && (half_byte & 0x4) != 0));
  75       if (more)
  76         half_byte |= 0x8;
  77
  78       bp_pack_value (bp, half_byte, 4);
  79     }
  80   while (more);
  81 }
  82
  83
  84 /* Unpack VAL from BP in a variant of uleb format.  */
  85
  86 unsigned HOST_WIDE_INT
  87 bp_unpack_var_len_unsigned (struct bitpack_d *bp)
  88 {
  89   unsigned HOST_WIDE_INT result = 0;
  90   int shift = 0;
  91   unsigned HOST_WIDE_INT half_byte;
  92
  93   while (true)
  94     {
  95       half_byte = bp_unpack_value (bp, 4);
  96       result |= (half_byte & 0x7) << shift;
  97       shift += 3;
  98       if ((half_byte & 0x8) == 0)
  99         return result;
 100     }
 101 }
 102
 103
 104 /* Unpack VAL from BP in a variant of sleb format.  */
 105
 106 HOST_WIDE_INT
 107 bp_unpack_var_len_int (struct bitpack_d *bp)
 108 {
 109   HOST_WIDE_INT result = 0;
 110   int shift = 0;
 111   unsigned HOST_WIDE_INT half_byte;
 112
 113   while (true)
 114     {
 115       half_byte = bp_unpack_value (bp, 4);
 116       result |= (half_byte & 0x7) << shift;
 117       shift += 3;
 118       if ((half_byte & 0x8) == 0)
 119         {
 120           if ((shift < HOST_BITS_PER_WIDE_INT) && (half_byte & 0x4))
 121             result |= - (HOST_WIDE_INT_1U << shift);
 122
 123           return result;
 124         }
 125     }
 126 }