1 /* Generic streaming support for various data types. 2 3 Copyright (C) 2011-2020 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_poly_uint64 (struct output_block *, poly_uint64); 57 void streamer_write_gcov_count (struct output_block *, gcov_type); 58 void streamer_write_string (struct output_block *, struct lto_output_stream *, 59 const char *, bool); 60 void streamer_write_string_with_length (struct output_block *, 61 struct lto_output_stream *, 62 const char *, unsigned int, bool); 63 void bp_pack_string_with_length (struct output_block *, struct bitpack_d *, 64 const char *, unsigned int, bool); 65 void bp_pack_string (struct output_block *, struct bitpack_d *, 66 const char *, bool); 67 void streamer_write_uhwi_stream (struct lto_output_stream *, 68 unsigned HOST_WIDE_INT); 69 void streamer_write_hwi_stream (struct lto_output_stream *, HOST_WIDE_INT); 70 void streamer_write_gcov_count_stream (struct lto_output_stream *, gcov_type); 71 void streamer_write_data_stream (struct lto_output_stream *, const void *, 72 size_t); 73 void streamer_write_wide_int (struct output_block *, const wide_int &); 74 void streamer_write_widest_int (struct output_block *, const widest_int &); 75 76 /* In data-streamer-in.c */ 77 const char *streamer_read_string (class data_in *, class lto_input_block *); 78 const char *streamer_read_indexed_string (class data_in *, 79 class lto_input_block *, 80 unsigned int *); 81 const char *bp_unpack_indexed_string (class data_in *, struct bitpack_d *, 82 unsigned int *); 83 const char *bp_unpack_string (class data_in *, struct bitpack_d *); 84 unsigned HOST_WIDE_INT streamer_read_uhwi (class lto_input_block *); 85 HOST_WIDE_INT streamer_read_hwi (class lto_input_block *); 86 poly_uint64 streamer_read_poly_uint64 (class lto_input_block *); 87 gcov_type streamer_read_gcov_count (class lto_input_block *); 88 wide_int streamer_read_wide_int (class lto_input_block *); 89 widest_int streamer_read_widest_int (class lto_input_block *); 90 91 /* Returns a new bit-packing context for bit-packing into S. */ 92 static inline struct bitpack_d 93 bitpack_create (struct lto_output_stream *s) 94 { 95 struct bitpack_d bp; 96 bp.pos = 0; 97 bp.word = 0; 98 bp.stream = (void *)s; 99 return bp; 100 } 101 102 /* Pack the NBITS bit sized value VAL into the bit-packing context BP. */ 103 static inline void 104 bp_pack_value (struct bitpack_d *bp, bitpack_word_t val, unsigned nbits) 105 { 106 bitpack_word_t word = bp->word; 107 int pos = bp->pos; 108 109 /* Verify that VAL fits in the NBITS. */ 110 gcc_checking_assert (nbits == BITS_PER_BITPACK_WORD 111 || !(val & ~(((bitpack_word_t)1<<nbits)-1))); 112 113 /* If val does not fit into the current bitpack word switch to the 114 next one. */ 115 if (pos + nbits > BITS_PER_BITPACK_WORD) 116 { 117 streamer_write_uhwi_stream ((struct lto_output_stream *) bp->stream, 118 word); 119 word = val; 120 pos = nbits; 121 } 122 else 123 { 124 word |= val << pos; 125 pos += nbits; 126 } 127 bp->word = word; 128 bp->pos = pos; 129 } 130 131 /* Pack VAL into the bit-packing context BP, using NBITS for each 132 coefficient. */ 133 static inline void 134 bp_pack_poly_value (struct bitpack_d *bp, 135 const poly_int<NUM_POLY_INT_COEFFS, bitpack_word_t> &val, 136 unsigned nbits) 137 { 138 for (int i = 0; i < NUM_POLY_INT_COEFFS; ++i) 139 bp_pack_value (bp, val.coeffs[i], nbits); 140 } 141 142 /* Finishes bit-packing of BP. */ 143 static inline void 144 streamer_write_bitpack (struct bitpack_d *bp) 145 { 146 streamer_write_uhwi_stream ((struct lto_output_stream *) bp->stream, 147 bp->word); 148 bp->word = 0; 149 bp->pos = 0; 150 } 151 152 /* Returns a new bit-packing context for bit-unpacking from IB. */ 153 static inline struct bitpack_d 154 streamer_read_bitpack (class lto_input_block *ib) 155 { 156 struct bitpack_d bp; 157 bp.word = streamer_read_uhwi (ib); 158 bp.pos = 0; 159 bp.stream = (void *)ib; 160 return bp; 161 } 162 163 /* Unpacks NBITS bits from the bit-packing context BP and returns them. */ 164 static inline bitpack_word_t 165 bp_unpack_value (struct bitpack_d *bp, unsigned nbits) 166 { 167 bitpack_word_t mask, val; 168 int pos = bp->pos; 169 170 mask = (nbits == BITS_PER_BITPACK_WORD 171 ? (bitpack_word_t) -1 172 : ((bitpack_word_t) 1 << nbits) - 1); 173 174 /* If there are not continuous nbits in the current bitpack word 175 switch to the next one. */ 176 if (pos + nbits > BITS_PER_BITPACK_WORD) 177 { 178 bp->word = val 179 = streamer_read_uhwi ((class lto_input_block *)bp->stream); 180 bp->pos = nbits; 181 return val & mask; 182 } 183 val = bp->word; 184 val >>= pos; 185 bp->pos = pos + nbits; 186 187 return val & mask; 188 } 189 190 /* Unpacks a polynomial value from the bit-packing context BP in which each 191 coefficient has NBITS bits. */ 192 static inline poly_int<NUM_POLY_INT_COEFFS, bitpack_word_t> 193 bp_unpack_poly_value (struct bitpack_d *bp, unsigned nbits) 194 { 195 poly_int_pod<NUM_POLY_INT_COEFFS, bitpack_word_t> x; 196 for (int i = 0; i < NUM_POLY_INT_COEFFS; ++i) 197 x.coeffs[i] = bp_unpack_value (bp, nbits); 198 return x; 199 } 200 201 202 /* Write a character to the output block. */ 203 204 static inline void 205 streamer_write_char_stream (struct lto_output_stream *obs, char c) 206 { 207 /* No space left. */ 208 if (obs->left_in_block == 0) 209 lto_append_block (obs); 210 211 /* Write the actual character. */ 212 char *current_pointer = obs->current_pointer; 213 *(current_pointer++) = c; 214 obs->current_pointer = current_pointer; 215 obs->total_size++; 216 obs->left_in_block--; 217 } 218 219 220 /* Read byte from the input block. */ 221 222 static inline unsigned char 223 streamer_read_uchar (class lto_input_block *ib) 224 { 225 if (ib->p >= ib->len) 226 lto_section_overrun (ib); 227 return (ib->data[ib->p++]); 228 } 229 230 /* Output VAL into OBS and verify it is in range MIN...MAX that is supposed 231 to be compile time constant. 232 Be host independent, limit range to 31bits. */ 233 234 static inline void 235 streamer_write_hwi_in_range (struct lto_output_stream *obs, 236 HOST_WIDE_INT min, 237 HOST_WIDE_INT max, 238 HOST_WIDE_INT val) 239 { 240 HOST_WIDE_INT range = max - min; 241 242 gcc_checking_assert (val >= min && val <= max && range > 0 243 && range < 0x7fffffff); 244 245 val -= min; 246 streamer_write_uhwi_stream (obs, (unsigned HOST_WIDE_INT) val); 247 } 248 249 /* Input VAL into OBS and verify it is in range MIN...MAX that is supposed 250 to be compile time constant. PURPOSE is used for error reporting. */ 251 252 static inline HOST_WIDE_INT 253 streamer_read_hwi_in_range (class lto_input_block *ib, 254 const char *purpose, 255 HOST_WIDE_INT min, 256 HOST_WIDE_INT max) 257 { 258 HOST_WIDE_INT range = max - min; 259 unsigned HOST_WIDE_INT uval = streamer_read_uhwi (ib); 260 261 gcc_checking_assert (range > 0 && range < 0x7fffffff); 262 263 HOST_WIDE_INT val = (HOST_WIDE_INT) (uval + (unsigned HOST_WIDE_INT) min); 264 if (val < min || val > max) 265 lto_value_range_error (purpose, val, min, max); 266 return val; 267 } 268 269 /* Output VAL into BP and verify it is in range MIN...MAX that is supposed 270 to be compile time constant. 271 Be host independent, limit range to 31bits. */ 272 273 static inline void 274 bp_pack_int_in_range (struct bitpack_d *bp, 275 HOST_WIDE_INT min, 276 HOST_WIDE_INT max, 277 HOST_WIDE_INT val) 278 { 279 HOST_WIDE_INT range = max - min; 280 int nbits = floor_log2 (range) + 1; 281 282 gcc_checking_assert (val >= min && val <= max && range > 0 283 && range < 0x7fffffff); 284 285 val -= min; 286 bp_pack_value (bp, val, nbits); 287 } 288 289 /* Input VAL into BP and verify it is in range MIN...MAX that is supposed 290 to be compile time constant. PURPOSE is used for error reporting. */ 291 292 static inline HOST_WIDE_INT 293 bp_unpack_int_in_range (struct bitpack_d *bp, 294 const char *purpose, 295 HOST_WIDE_INT min, 296 HOST_WIDE_INT max) 297 { 298 HOST_WIDE_INT range = max - min; 299 int nbits = floor_log2 (range) + 1; 300 HOST_WIDE_INT val = bp_unpack_value (bp, nbits); 301 302 gcc_checking_assert (range > 0 && range < 0x7fffffff); 303 304 if (val < min || val > max) 305 lto_value_range_error (purpose, val, min, max); 306 return val; 307 } 308 309 /* Output VAL of type "enum enum_name" into OBS. 310 Assume range 0...ENUM_LAST - 1. */ 311 #define streamer_write_enum(obs,enum_name,enum_last,val) \ 312 streamer_write_hwi_in_range ((obs), 0, (int)(enum_last) - 1, (int)(val)) 313 314 /* Input enum of type "enum enum_name" from IB. 315 Assume range 0...ENUM_LAST - 1. */ 316 #define streamer_read_enum(ib,enum_name,enum_last) \ 317 (enum enum_name)streamer_read_hwi_in_range ((ib), #enum_name, 0, \ 318 (int)(enum_last) - 1) 319 320 /* Output VAL of type "enum enum_name" into BP. 321 Assume range 0...ENUM_LAST - 1. */ 322 #define bp_pack_enum(bp,enum_name,enum_last,val) \ 323 bp_pack_int_in_range ((bp), 0, (int)(enum_last) - 1, (int)(val)) 324 325 /* Input enum of type "enum enum_name" from BP. 326 Assume range 0...ENUM_LAST - 1. */ 327 #define bp_unpack_enum(bp,enum_name,enum_last) \ 328 (enum enum_name)bp_unpack_int_in_range ((bp), #enum_name, 0, \ 329 (int)(enum_last) - 1) 330 331 /* Output the start of a record with TAG to output block OB. */ 332 333 static inline void 334 streamer_write_record_start (struct output_block *ob, enum LTO_tags tag) 335 { 336 streamer_write_enum (ob->main_stream, LTO_tags, LTO_NUM_TAGS, tag); 337 } 338 339 /* Return the next tag in the input block IB. */ 340 341 static inline enum LTO_tags 342 streamer_read_record_start (class lto_input_block *ib) 343 { 344 return streamer_read_enum (ib, LTO_tags, LTO_NUM_TAGS); 345 } 346 347 #endif /* GCC_DATA_STREAMER_H */ 348