1 /* Generic streaming support for various data types. 2 3 Copyright (C) 2011-2018 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 #ifndef GCC_DATA_STREAMER_H 23 #define GCC_DATA_STREAMER_H 24 25 #include "lto-streamer.h" 26 27 /* Data structures used to pack values and bitflags into a vector of 28 words. Used to stream values of a fixed number of bits in a space 29 efficient way. */ 30 static unsigned const BITS_PER_BITPACK_WORD = HOST_BITS_PER_WIDE_INT; 31 32 typedef unsigned HOST_WIDE_INT bitpack_word_t; 33 34 struct bitpack_d 35 { 36 /* The position of the first unused or unconsumed bit in the word. */ 37 unsigned pos; 38 39 /* The current word we are (un)packing. */ 40 bitpack_word_t word; 41 42 /* The lto_output_stream or the lto_input_block we are streaming to/from. */ 43 void *stream; 44 }; 45 46 /* In data-streamer.c */ 47 void bp_pack_var_len_unsigned (struct bitpack_d *, unsigned HOST_WIDE_INT); 48 void bp_pack_var_len_int (struct bitpack_d *, HOST_WIDE_INT); 49 unsigned HOST_WIDE_INT bp_unpack_var_len_unsigned (struct bitpack_d *); 50 HOST_WIDE_INT bp_unpack_var_len_int (struct bitpack_d *); 51 52 /* In data-streamer-out.c */ 53 void streamer_write_zero (struct output_block *); 54 void streamer_write_uhwi (struct output_block *, unsigned HOST_WIDE_INT); 55 void streamer_write_hwi (struct output_block *, HOST_WIDE_INT); 56 void streamer_write_gcov_count (struct output_block *, gcov_type); 57 void streamer_write_string (struct output_block *, struct lto_output_stream *, 58 const char *, bool); 59 void streamer_write_string_with_length (struct output_block *, 60 struct lto_output_stream *, 61 const char *, unsigned int, bool); 62 void bp_pack_string_with_length (struct output_block *, struct bitpack_d *, 63 const char *, unsigned int, bool); 64 void bp_pack_string (struct output_block *, struct bitpack_d *, 65 const char *, bool); 66 void streamer_write_uhwi_stream (struct lto_output_stream *, 67 unsigned HOST_WIDE_INT); 68 void streamer_write_hwi_stream (struct lto_output_stream *, HOST_WIDE_INT); 69 void streamer_write_gcov_count_stream (struct lto_output_stream *, gcov_type); 70 void streamer_write_data_stream (struct lto_output_stream *, const void *, 71 size_t); 72 void streamer_write_wide_int (struct output_block *, const wide_int &); 73 void streamer_write_widest_int (struct output_block *, const widest_int &); 74 75 /* In data-streamer-in.c */ 76 const char *streamer_read_string (struct data_in *, struct lto_input_block *); 77 const char *streamer_read_indexed_string (struct data_in *, 78 struct lto_input_block *, 79 unsigned int *); 80 const char *bp_unpack_indexed_string (struct data_in *, struct bitpack_d *, 81 unsigned int *); 82 const char *bp_unpack_string (struct data_in *, struct bitpack_d *); 83 unsigned HOST_WIDE_INT streamer_read_uhwi (struct lto_input_block *); 84 HOST_WIDE_INT streamer_read_hwi (struct lto_input_block *); 85 gcov_type streamer_read_gcov_count (struct lto_input_block *); 86 wide_int streamer_read_wide_int (struct lto_input_block *); 87 widest_int streamer_read_widest_int (struct lto_input_block *); 88 89 /* Returns a new bit-packing context for bit-packing into S. */ 90 static inline struct bitpack_d 91 bitpack_create (struct lto_output_stream *s) 92 { 93 struct bitpack_d bp; 94 bp.pos = 0; 95 bp.word = 0; 96 bp.stream = (void *)s; 97 return bp; 98 } 99 100 /* Pack the NBITS bit sized value VAL into the bit-packing context BP. */ 101 static inline void 102 bp_pack_value (struct bitpack_d *bp, bitpack_word_t val, unsigned nbits) 103 { 104 bitpack_word_t word = bp->word; 105 int pos = bp->pos; 106 107 /* Verify that VAL fits in the NBITS. */ 108 gcc_checking_assert (nbits == BITS_PER_BITPACK_WORD 109 || !(val & ~(((bitpack_word_t)1<<nbits)-1))); 110 111 /* If val does not fit into the current bitpack word switch to the 112 next one. */ 113 if (pos + nbits > BITS_PER_BITPACK_WORD) 114 { 115 streamer_write_uhwi_stream ((struct lto_output_stream *) bp->stream, 116 word); 117 word = val; 118 pos = nbits; 119 } 120 else 121 { 122 word |= val << pos; 123 pos += nbits; 124 } 125 bp->word = word; 126 bp->pos = pos; 127 } 128 129 /* Pack VAL into the bit-packing context BP, using NBITS for each 130 coefficient. */ 131 static inline void 132 bp_pack_poly_value (struct bitpack_d *bp, 133 const poly_int<NUM_POLY_INT_COEFFS, bitpack_word_t> &val, 134 unsigned nbits) 135 { 136 for (int i = 0; i < NUM_POLY_INT_COEFFS; ++i) 137 bp_pack_value (bp, val.coeffs[i], nbits); 138 } 139 140 /* Finishes bit-packing of BP. */ 141 static inline void 142 streamer_write_bitpack (struct bitpack_d *bp) 143 { 144 streamer_write_uhwi_stream ((struct lto_output_stream *) bp->stream, 145 bp->word); 146 bp->word = 0; 147 bp->pos = 0; 148 } 149 150 /* Returns a new bit-packing context for bit-unpacking from IB. */ 151 static inline struct bitpack_d 152 streamer_read_bitpack (struct lto_input_block *ib) 153 { 154 struct bitpack_d bp; 155 bp.word = streamer_read_uhwi (ib); 156 bp.pos = 0; 157 bp.stream = (void *)ib; 158 return bp; 159 } 160 161 /* Unpacks NBITS bits from the bit-packing context BP and returns them. */ 162 static inline bitpack_word_t 163 bp_unpack_value (struct bitpack_d *bp, unsigned nbits) 164 { 165 bitpack_word_t mask, val; 166 int pos = bp->pos; 167 168 mask = (nbits == BITS_PER_BITPACK_WORD 169 ? (bitpack_word_t) -1 170 : ((bitpack_word_t) 1 << nbits) - 1); 171 172 /* If there are not continuous nbits in the current bitpack word 173 switch to the next one. */ 174 if (pos + nbits > BITS_PER_BITPACK_WORD) 175 { 176 bp->word = val 177 = streamer_read_uhwi ((struct lto_input_block *)bp->stream); 178 bp->pos = nbits; 179 return val & mask; 180 } 181 val = bp->word; 182 val >>= pos; 183 bp->pos = pos + nbits; 184 185 return val & mask; 186 } 187 188 /* Unpacks a polynomial value from the bit-packing context BP in which each 189 coefficient has NBITS bits. */ 190 static inline poly_int<NUM_POLY_INT_COEFFS, bitpack_word_t> 191 bp_unpack_poly_value (struct bitpack_d *bp, unsigned nbits) 192 { 193 poly_int_pod<NUM_POLY_INT_COEFFS, bitpack_word_t> x; 194 for (int i = 0; i < NUM_POLY_INT_COEFFS; ++i) 195 x.coeffs[i] = bp_unpack_value (bp, nbits); 196 return x; 197 } 198 199 200 /* Write a character to the output block. */ 201 202 static inline void 203 streamer_write_char_stream (struct lto_output_stream *obs, char c) 204 { 205 /* No space left. */ 206 if (obs->left_in_block == 0) 207 lto_append_block (obs); 208 209 /* Write the actual character. */ 210 char *current_pointer = obs->current_pointer; 211 *(current_pointer++) = c; 212 obs->current_pointer = current_pointer; 213 obs->total_size++; 214 obs->left_in_block--; 215 } 216 217 218 /* Read byte from the input block. */ 219 220 static inline unsigned char 221 streamer_read_uchar (struct lto_input_block *ib) 222 { 223 if (ib->p >= ib->len) 224 lto_section_overrun (ib); 225 return (ib->data[ib->p++]); 226 } 227 228 /* Output VAL into OBS and verify it is in range MIN...MAX that is supposed 229 to be compile time constant. 230 Be host independent, limit range to 31bits. */ 231 232 static inline void 233 streamer_write_hwi_in_range (struct lto_output_stream *obs, 234 HOST_WIDE_INT min, 235 HOST_WIDE_INT max, 236 HOST_WIDE_INT val) 237 { 238 HOST_WIDE_INT range = max - min; 239 240 gcc_checking_assert (val >= min && val <= max && range > 0 241 && range < 0x7fffffff); 242 243 val -= min; 244 streamer_write_uhwi_stream (obs, (unsigned HOST_WIDE_INT) val); 245 } 246 247 /* Input VAL into OBS and verify it is in range MIN...MAX that is supposed 248 to be compile time constant. PURPOSE is used for error reporting. */ 249 250 static inline HOST_WIDE_INT 251 streamer_read_hwi_in_range (struct lto_input_block *ib, 252 const char *purpose, 253 HOST_WIDE_INT min, 254 HOST_WIDE_INT max) 255 { 256 HOST_WIDE_INT range = max - min; 257 unsigned HOST_WIDE_INT uval = streamer_read_uhwi (ib); 258 259 gcc_checking_assert (range > 0 && range < 0x7fffffff); 260 261 HOST_WIDE_INT val = (HOST_WIDE_INT) (uval + (unsigned HOST_WIDE_INT) min); 262 if (val < min || val > max) 263 lto_value_range_error (purpose, val, min, max); 264 return val; 265 } 266 267 /* Output VAL into BP and verify it is in range MIN...MAX that is supposed 268 to be compile time constant. 269 Be host independent, limit range to 31bits. */ 270 271 static inline void 272 bp_pack_int_in_range (struct bitpack_d *bp, 273 HOST_WIDE_INT min, 274 HOST_WIDE_INT max, 275 HOST_WIDE_INT val) 276 { 277 HOST_WIDE_INT range = max - min; 278 int nbits = floor_log2 (range) + 1; 279 280 gcc_checking_assert (val >= min && val <= max && range > 0 281 && range < 0x7fffffff); 282 283 val -= min; 284 bp_pack_value (bp, val, nbits); 285 } 286 287 /* Input VAL into BP and verify it is in range MIN...MAX that is supposed 288 to be compile time constant. PURPOSE is used for error reporting. */ 289 290 static inline HOST_WIDE_INT 291 bp_unpack_int_in_range (struct bitpack_d *bp, 292 const char *purpose, 293 HOST_WIDE_INT min, 294 HOST_WIDE_INT max) 295 { 296 HOST_WIDE_INT range = max - min; 297 int nbits = floor_log2 (range) + 1; 298 HOST_WIDE_INT val = bp_unpack_value (bp, nbits); 299 300 gcc_checking_assert (range > 0 && range < 0x7fffffff); 301 302 if (val < min || val > max) 303 lto_value_range_error (purpose, val, min, max); 304 return val; 305 } 306 307 /* Output VAL of type "enum enum_name" into OBS. 308 Assume range 0...ENUM_LAST - 1. */ 309 #define streamer_write_enum(obs,enum_name,enum_last,val) \ 310 streamer_write_hwi_in_range ((obs), 0, (int)(enum_last) - 1, (int)(val)) 311 312 /* Input enum of type "enum enum_name" from IB. 313 Assume range 0...ENUM_LAST - 1. */ 314 #define streamer_read_enum(ib,enum_name,enum_last) \ 315 (enum enum_name)streamer_read_hwi_in_range ((ib), #enum_name, 0, \ 316 (int)(enum_last) - 1) 317 318 /* Output VAL of type "enum enum_name" into BP. 319 Assume range 0...ENUM_LAST - 1. */ 320 #define bp_pack_enum(bp,enum_name,enum_last,val) \ 321 bp_pack_int_in_range ((bp), 0, (int)(enum_last) - 1, (int)(val)) 322 323 /* Input enum of type "enum enum_name" from BP. 324 Assume range 0...ENUM_LAST - 1. */ 325 #define bp_unpack_enum(bp,enum_name,enum_last) \ 326 (enum enum_name)bp_unpack_int_in_range ((bp), #enum_name, 0, \ 327 (int)(enum_last) - 1) 328 329 /* Output the start of a record with TAG to output block OB. */ 330 331 static inline void 332 streamer_write_record_start (struct output_block *ob, enum LTO_tags tag) 333 { 334 streamer_write_enum (ob->main_stream, LTO_tags, LTO_NUM_TAGS, tag); 335 } 336 337 /* Return the next tag in the input block IB. */ 338 339 static inline enum LTO_tags 340 streamer_read_record_start (struct lto_input_block *ib) 341 { 342 return streamer_read_enum (ib, LTO_tags, LTO_NUM_TAGS); 343 } 344 345 #endif /* GCC_DATA_STREAMER_H */ 346