1 /* Generic streaming support for various data types.
3 Copyright 2011 Free Software Foundation, Inc.
4 Contributed by Diego Novillo <dnovillo@google.com>
6 This file is part of GCC.
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
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
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/>. */
22 #ifndef GCC_DATA_STREAMER_H
23 #define GCC_DATA_STREAMER_H
26 #include "lto-streamer.h"
28 /* Data structures used to pack values and bitflags into a vector of
29 words. Used to stream values of a fixed number of bits in a space
31 static unsigned const BITS_PER_BITPACK_WORD = HOST_BITS_PER_WIDE_INT;
33 typedef unsigned HOST_WIDE_INT bitpack_word_t;
34 DEF_VEC_I(bitpack_word_t);
35 DEF_VEC_ALLOC_I(bitpack_word_t, heap);
39 /* The position of the first unused or unconsumed bit in the word. */
42 /* The current word we are (un)packing. */
45 /* The lto_output_stream or the lto_input_block we are streaming to/from. */
55 unsigned int slot_num;
58 /* In data-streamer.c */
59 void bp_pack_var_len_unsigned (struct bitpack_d *, unsigned HOST_WIDE_INT);
60 void bp_pack_var_len_int (struct bitpack_d *, HOST_WIDE_INT);
61 unsigned HOST_WIDE_INT bp_unpack_var_len_unsigned (struct bitpack_d *);
62 HOST_WIDE_INT bp_unpack_var_len_int (struct bitpack_d *);
64 /* In data-streamer-out.c */
65 void streamer_write_zero (struct output_block *);
66 void streamer_write_uhwi (struct output_block *, unsigned HOST_WIDE_INT);
67 void streamer_write_hwi (struct output_block *, HOST_WIDE_INT);
68 void streamer_write_string (struct output_block *, struct lto_output_stream *,
70 unsigned streamer_string_index (struct output_block *, const char *,
72 void streamer_write_string_with_length (struct output_block *,
73 struct lto_output_stream *,
74 const char *, unsigned int, bool);
75 void streamer_write_uhwi_stream (struct lto_output_stream *,
76 unsigned HOST_WIDE_INT);
77 void streamer_write_hwi_stream (struct lto_output_stream *, HOST_WIDE_INT);
79 /* In data-streamer-in.c */
80 const char *string_for_index (struct data_in *, unsigned int, unsigned int *);
81 const char *streamer_read_string (struct data_in *, struct lto_input_block *);
82 const char *streamer_read_indexed_string (struct data_in *,
83 struct lto_input_block *,
85 unsigned HOST_WIDE_INT streamer_read_uhwi (struct lto_input_block *);
86 HOST_WIDE_INT streamer_read_hwi (struct lto_input_block *);
88 /* Returns a hash code for P. Adapted from libiberty's htab_hash_string
89 to support strings that may not end in '\0'. */
91 static inline hashval_t
92 hash_string_slot_node (const void *p)
94 const struct string_slot *ds = (const struct string_slot *) p;
95 hashval_t r = ds->len;
98 for (i = 0; i < ds->len; i++)
99 r = r * 67 + (unsigned)ds->s[i] - 113;
103 /* Returns nonzero if P1 and P2 are equal. */
106 eq_string_slot_node (const void *p1, const void *p2)
108 const struct string_slot *ds1 = (const struct string_slot *) p1;
109 const struct string_slot *ds2 = (const struct string_slot *) p2;
111 if (ds1->len == ds2->len)
112 return memcmp (ds1->s, ds2->s, ds1->len) == 0;
117 /* Returns a new bit-packing context for bit-packing into S. */
118 static inline struct bitpack_d
119 bitpack_create (struct lto_output_stream *s)
124 bp.stream = (void *)s;
128 /* Pack the NBITS bit sized value VAL into the bit-packing context BP. */
130 bp_pack_value (struct bitpack_d *bp, bitpack_word_t val, unsigned nbits)
132 bitpack_word_t word = bp->word;
135 /* Verify that VAL fits in the NBITS. */
136 gcc_checking_assert (nbits == BITS_PER_BITPACK_WORD
137 || !(val & ~(((bitpack_word_t)1<<nbits)-1)));
139 /* If val does not fit into the current bitpack word switch to the
141 if (pos + nbits > BITS_PER_BITPACK_WORD)
143 streamer_write_uhwi_stream ((struct lto_output_stream *) bp->stream,
157 /* Finishes bit-packing of BP. */
159 streamer_write_bitpack (struct bitpack_d *bp)
161 streamer_write_uhwi_stream ((struct lto_output_stream *) bp->stream,
167 /* Returns a new bit-packing context for bit-unpacking from IB. */
168 static inline struct bitpack_d
169 streamer_read_bitpack (struct lto_input_block *ib)
172 bp.word = streamer_read_uhwi (ib);
174 bp.stream = (void *)ib;
178 /* Unpacks NBITS bits from the bit-packing context BP and returns them. */
179 static inline bitpack_word_t
180 bp_unpack_value (struct bitpack_d *bp, unsigned nbits)
182 bitpack_word_t mask, val;
185 mask = (nbits == BITS_PER_BITPACK_WORD
186 ? (bitpack_word_t) -1
187 : ((bitpack_word_t) 1 << nbits) - 1);
189 /* If there are not continuous nbits in the current bitpack word
190 switch to the next one. */
191 if (pos + nbits > BITS_PER_BITPACK_WORD)
194 = streamer_read_uhwi ((struct lto_input_block *)bp->stream);
200 bp->pos = pos + nbits;
206 /* Write a character to the output block. */
209 streamer_write_char_stream (struct lto_output_stream *obs, char c)
212 if (obs->left_in_block == 0)
213 lto_append_block (obs);
215 /* Write the actual character. */
216 *obs->current_pointer = c;
217 obs->current_pointer++;
219 obs->left_in_block--;
223 /* Read byte from the input block. */
225 static inline unsigned char
226 streamer_read_uchar (struct lto_input_block *ib)
228 if (ib->p >= ib->len)
229 lto_section_overrun (ib);
230 return (ib->data[ib->p++]);
233 /* Output VAL into OBS and verify it is in range MIN...MAX that is supposed
234 to be compile time constant.
235 Be host independent, limit range to 31bits. */
238 streamer_write_hwi_in_range (struct lto_output_stream *obs,
243 HOST_WIDE_INT range = max - min;
245 gcc_checking_assert (val >= min && val <= max && range > 0
246 && range < 0x7fffffff);
249 streamer_write_char_stream (obs, val & 255);
251 streamer_write_char_stream (obs, (val >> 8) & 255);
253 streamer_write_char_stream (obs, (val >> 16) & 255);
254 if (range >= 0xffffff)
255 streamer_write_char_stream (obs, (val >> 24) & 255);
258 /* Input VAL into OBS and verify it is in range MIN...MAX that is supposed
259 to be compile time constant. PURPOSE is used for error reporting. */
261 static inline HOST_WIDE_INT
262 streamer_read_hwi_in_range (struct lto_input_block *ib,
267 HOST_WIDE_INT range = max - min;
268 HOST_WIDE_INT val = streamer_read_uchar (ib);
270 gcc_checking_assert (range > 0 && range < 0x7fffffff);
273 val |= ((HOST_WIDE_INT)streamer_read_uchar (ib)) << 8;
275 val |= ((HOST_WIDE_INT)streamer_read_uchar (ib)) << 16;
276 if (range >= 0xffffff)
277 val |= ((HOST_WIDE_INT)streamer_read_uchar (ib)) << 24;
279 if (val < min || val > max)
280 lto_value_range_error (purpose, val, min, max);
284 /* Output VAL into BP and verify it is in range MIN...MAX that is supposed
285 to be compile time constant.
286 Be host independent, limit range to 31bits. */
289 bp_pack_int_in_range (struct bitpack_d *bp,
294 HOST_WIDE_INT range = max - min;
295 int nbits = floor_log2 (range) + 1;
297 gcc_checking_assert (val >= min && val <= max && range > 0
298 && range < 0x7fffffff);
301 bp_pack_value (bp, val, nbits);
304 /* Input VAL into BP and verify it is in range MIN...MAX that is supposed
305 to be compile time constant. PURPOSE is used for error reporting. */
307 static inline HOST_WIDE_INT
308 bp_unpack_int_in_range (struct bitpack_d *bp,
313 HOST_WIDE_INT range = max - min;
314 int nbits = floor_log2 (range) + 1;
315 HOST_WIDE_INT val = bp_unpack_value (bp, nbits);
317 gcc_checking_assert (range > 0 && range < 0x7fffffff);
319 if (val < min || val > max)
320 lto_value_range_error (purpose, val, min, max);
324 /* Output VAL of type "enum enum_name" into OBS.
325 Assume range 0...ENUM_LAST - 1. */
326 #define streamer_write_enum(obs,enum_name,enum_last,val) \
327 streamer_write_hwi_in_range ((obs), 0, (int)(enum_last) - 1, (int)(val))
329 /* Input enum of type "enum enum_name" from IB.
330 Assume range 0...ENUM_LAST - 1. */
331 #define streamer_read_enum(ib,enum_name,enum_last) \
332 (enum enum_name)streamer_read_hwi_in_range ((ib), #enum_name, 0, \
333 (int)(enum_last) - 1)
335 /* Output VAL of type "enum enum_name" into BP.
336 Assume range 0...ENUM_LAST - 1. */
337 #define bp_pack_enum(bp,enum_name,enum_last,val) \
338 bp_pack_int_in_range ((bp), 0, (int)(enum_last) - 1, (int)(val))
340 /* Input enum of type "enum enum_name" from BP.
341 Assume range 0...ENUM_LAST - 1. */
342 #define bp_unpack_enum(bp,enum_name,enum_last) \
343 (enum enum_name)bp_unpack_int_in_range ((bp), #enum_name, 0, \
344 (int)(enum_last) - 1)
346 /* Output the start of a record with TAG to output block OB. */
349 streamer_write_record_start (struct output_block *ob, enum LTO_tags tag)
351 streamer_write_enum (ob->main_stream, LTO_tags, LTO_NUM_TAGS, tag);
354 /* Return the next tag in the input block IB. */
356 static inline enum LTO_tags
357 streamer_read_record_start (struct lto_input_block *ib)
359 return streamer_read_enum (ib, LTO_tags, LTO_NUM_TAGS);
362 #endif /* GCC_DATA_STREAMER_H */