1/* Routines for restoring various data types from a file stream. This deals 2 with various data types like strings, integers, enums, etc. 3 4 Copyright (C) 2011-2015 Free Software Foundation, Inc. 5 Contributed by Diego Novillo <dnovillo@google.com> 6 7This file is part of GCC. 8 9GCC is free software; you can redistribute it and/or modify it under 10the terms of the GNU General Public License as published by the Free 11Software Foundation; either version 3, or (at your option) any later 12version. 13 14GCC is distributed in the hope that it will be useful, but WITHOUT ANY 15WARRANTY; without even the implied warranty of MERCHANTABILITY or 16FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 17for more details. 18 19You should have received a copy of the GNU General Public License 20along 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 "diagnostic.h" 27#include "hash-set.h" 28#include "machmode.h" 29#include "vec.h" 30#include "double-int.h" 31#include "input.h" 32#include "alias.h" 33#include "symtab.h" 34#include "options.h" 35#include "wide-int.h" 36#include "inchash.h" 37#include "tree.h" 38#include "fold-const.h" 39#include "predict.h" 40#include "vec.h" 41#include "tm.h" 42#include "hard-reg-set.h" 43#include "input.h" 44#include "function.h" 45#include "basic-block.h" 46#include "tree-ssa-alias.h" 47#include "internal-fn.h" 48#include "gimple-expr.h" 49#include "is-a.h" 50#include "gimple.h" 51#include "hash-map.h" 52#include "plugin-api.h" 53#include "ipa-ref.h" 54#include "cgraph.h" 55#include "data-streamer.h" 56 57/* Read a string from the string table in DATA_IN using input block 58 IB. Write the length to RLEN. */ 59 60static const char * 61string_for_index (struct data_in *data_in, unsigned int loc, unsigned int *rlen) 62{ 63 unsigned int len; 64 const char *result; 65 66 if (!loc) 67 { 68 *rlen = 0; 69 return NULL; 70 } 71 72 /* Get the string stored at location LOC in DATA_IN->STRINGS. */ 73 lto_input_block str_tab (data_in->strings, loc - 1, data_in->strings_len, NULL); 74 len = streamer_read_uhwi (&str_tab); 75 *rlen = len; 76 77 if (str_tab.p + len > data_in->strings_len) 78 internal_error ("bytecode stream: string too long for the string table"); 79 80 result = (const char *)(data_in->strings + str_tab.p); 81 82 return result; 83} 84 85 86/* Read a string from the string table in DATA_IN using input block 87 IB. Write the length to RLEN. */ 88 89const char * 90streamer_read_indexed_string (struct data_in *data_in, 91 struct lto_input_block *ib, unsigned int *rlen) 92{ 93 return string_for_index (data_in, streamer_read_uhwi (ib), rlen); 94} 95 96 97/* Read a NULL terminated string from the string table in DATA_IN. */ 98 99const char * 100streamer_read_string (struct data_in *data_in, struct lto_input_block *ib) 101{ 102 unsigned int len; 103 const char *ptr; 104 105 ptr = streamer_read_indexed_string (data_in, ib, &len); 106 if (!ptr) 107 return NULL; 108 if (ptr[len - 1] != '\0') 109 internal_error ("bytecode stream: found non-null terminated string"); 110 111 return ptr; 112} 113 114 115/* Read a string from the string table in DATA_IN using the bitpack BP. 116 Write the length to RLEN. */ 117 118const char * 119bp_unpack_indexed_string (struct data_in *data_in, 120 struct bitpack_d *bp, unsigned int *rlen) 121{ 122 return string_for_index (data_in, bp_unpack_var_len_unsigned (bp), rlen); 123} 124 125 126/* Read a NULL terminated string from the string table in DATA_IN. */ 127 128const char * 129bp_unpack_string (struct data_in *data_in, struct bitpack_d *bp) 130{ 131 unsigned int len; 132 const char *ptr; 133 134 ptr = bp_unpack_indexed_string (data_in, bp, &len); 135 if (!ptr) 136 return NULL; 137 if (ptr[len - 1] != '\0') 138 internal_error ("bytecode stream: found non-null terminated string"); 139 140 return ptr; 141} 142 143 144/* Read an unsigned HOST_WIDE_INT number from IB. */ 145 146unsigned HOST_WIDE_INT 147streamer_read_uhwi (struct lto_input_block *ib) 148{ 149 unsigned HOST_WIDE_INT result; 150 int shift; 151 unsigned HOST_WIDE_INT byte; 152 unsigned int p = ib->p; 153 unsigned int len = ib->len; 154 155 const char *data = ib->data; 156 result = data[p++]; 157 if ((result & 0x80) != 0) 158 { 159 result &= 0x7f; 160 shift = 7; 161 do 162 { 163 byte = data[p++]; 164 result |= (byte & 0x7f) << shift; 165 shift += 7; 166 } 167 while ((byte & 0x80) != 0); 168 } 169 170 /* We check for section overrun after the fact for performance reason. */ 171 if (p > len) 172 lto_section_overrun (ib); 173 174 ib->p = p; 175 return result; 176} 177 178 179/* Read a HOST_WIDE_INT number from IB. */ 180 181HOST_WIDE_INT 182streamer_read_hwi (struct lto_input_block *ib) 183{ 184 HOST_WIDE_INT result = 0; 185 int shift = 0; 186 unsigned HOST_WIDE_INT byte; 187 188 while (true) 189 { 190 byte = streamer_read_uchar (ib); 191 result |= (byte & 0x7f) << shift; 192 shift += 7; 193 if ((byte & 0x80) == 0) 194 { 195 if ((shift < HOST_BITS_PER_WIDE_INT) && (byte & 0x40)) 196 result |= - (HOST_WIDE_INT_1U << shift); 197 198 return result; 199 } 200 } 201} 202 203/* Read gcov_type value from IB. */ 204 205gcov_type 206streamer_read_gcov_count (struct lto_input_block *ib) 207{ 208 gcov_type ret = streamer_read_hwi (ib); 209 gcc_assert (ret >= 0); 210 return ret; 211} 212