1 /* 2 * Copyright (c) Meta Platforms, Inc. and affiliates. 3 * All rights reserved. 4 * 5 * This source code is licensed under both the BSD-style license (found in the 6 * LICENSE file in the root directory of this source tree) and the GPLv2 (found 7 * in the COPYING file in the root directory of this source tree). 8 * You may select, at your option, one of the above-listed licenses. 9 */ 10 11 #ifndef ZSTD_CCOMMON_H_MODULE 12 #define ZSTD_CCOMMON_H_MODULE 13 14 /* this module contains definitions which must be identical 15 * across compression, decompression and dictBuilder. 16 * It also contains a few functions useful to at least 2 of them 17 * and which benefit from being inlined */ 18 19 /*-************************************* 20 * Dependencies 21 ***************************************/ 22 #include "compiler.h" 23 #include "cpu.h" 24 #include "mem.h" 25 #include "debug.h" /* assert, DEBUGLOG, RAWLOG, g_debuglevel */ 26 #include "error_private.h" 27 #define ZSTD_STATIC_LINKING_ONLY 28 #include "../zstd.h" 29 #define FSE_STATIC_LINKING_ONLY 30 #include "fse.h" 31 #include "huf.h" 32 #ifndef XXH_STATIC_LINKING_ONLY 33 # define XXH_STATIC_LINKING_ONLY /* XXH64_state_t */ 34 #endif 35 #include "xxhash.h" /* XXH_reset, update, digest */ 36 #ifndef ZSTD_NO_TRACE 37 # include "zstd_trace.h" 38 #else 39 # define ZSTD_TRACE 0 40 #endif 41 42 #if defined (__cplusplus) 43 extern "C" { 44 #endif 45 46 /* ---- static assert (debug) --- */ 47 #define ZSTD_STATIC_ASSERT(c) DEBUG_STATIC_ASSERT(c) 48 #define ZSTD_isError ERR_isError /* for inlining */ 49 #define FSE_isError ERR_isError 50 #define HUF_isError ERR_isError 51 52 53 /*-************************************* 54 * shared macros 55 ***************************************/ 56 #undef MIN 57 #undef MAX 58 #define MIN(a,b) ((a)<(b) ? (a) : (b)) 59 #define MAX(a,b) ((a)>(b) ? (a) : (b)) 60 #define BOUNDED(min,val,max) (MAX(min,MIN(val,max))) 61 62 63 /*-************************************* 64 * Common constants 65 ***************************************/ 66 #define ZSTD_OPT_NUM (1<<12) 67 68 #define ZSTD_REP_NUM 3 /* number of repcodes */ 69 static UNUSED_ATTR const U32 repStartValue[ZSTD_REP_NUM] = { 1, 4, 8 }; 70 71 #define KB *(1 <<10) 72 #define MB *(1 <<20) 73 #define GB *(1U<<30) 74 75 #define BIT7 128 76 #define BIT6 64 77 #define BIT5 32 78 #define BIT4 16 79 #define BIT1 2 80 #define BIT0 1 81 82 #define ZSTD_WINDOWLOG_ABSOLUTEMIN 10 83 static UNUSED_ATTR const size_t ZSTD_fcs_fieldSize[4] = { 0, 2, 4, 8 }; 84 static UNUSED_ATTR const size_t ZSTD_did_fieldSize[4] = { 0, 1, 2, 4 }; 85 86 #define ZSTD_FRAMEIDSIZE 4 /* magic number size */ 87 88 #define ZSTD_BLOCKHEADERSIZE 3 /* C standard doesn't allow `static const` variable to be init using another `static const` variable */ 89 static UNUSED_ATTR const size_t ZSTD_blockHeaderSize = ZSTD_BLOCKHEADERSIZE; 90 typedef enum { bt_raw, bt_rle, bt_compressed, bt_reserved } blockType_e; 91 92 #define ZSTD_FRAMECHECKSUMSIZE 4 93 94 #define MIN_SEQUENCES_SIZE 1 /* nbSeq==0 */ 95 #define MIN_CBLOCK_SIZE (1 /*litCSize*/ + 1 /* RLE or RAW */) /* for a non-null block */ 96 #define MIN_LITERALS_FOR_4_STREAMS 6 97 98 typedef enum { set_basic, set_rle, set_compressed, set_repeat } symbolEncodingType_e; 99 100 #define LONGNBSEQ 0x7F00 101 102 #define MINMATCH 3 103 104 #define Litbits 8 105 #define LitHufLog 11 106 #define MaxLit ((1<<Litbits) - 1) 107 #define MaxML 52 108 #define MaxLL 35 109 #define DefaultMaxOff 28 110 #define MaxOff 31 111 #define MaxSeq MAX(MaxLL, MaxML) /* Assumption : MaxOff < MaxLL,MaxML */ 112 #define MLFSELog 9 113 #define LLFSELog 9 114 #define OffFSELog 8 115 #define MaxFSELog MAX(MAX(MLFSELog, LLFSELog), OffFSELog) 116 #define MaxMLBits 16 117 #define MaxLLBits 16 118 119 #define ZSTD_MAX_HUF_HEADER_SIZE 128 /* header + <= 127 byte tree description */ 120 /* Each table cannot take more than #symbols * FSELog bits */ 121 #define ZSTD_MAX_FSE_HEADERS_SIZE (((MaxML + 1) * MLFSELog + (MaxLL + 1) * LLFSELog + (MaxOff + 1) * OffFSELog + 7) / 8) 122 123 static UNUSED_ATTR const U8 LL_bits[MaxLL+1] = { 124 0, 0, 0, 0, 0, 0, 0, 0, 125 0, 0, 0, 0, 0, 0, 0, 0, 126 1, 1, 1, 1, 2, 2, 3, 3, 127 4, 6, 7, 8, 9,10,11,12, 128 13,14,15,16 129 }; 130 static UNUSED_ATTR const S16 LL_defaultNorm[MaxLL+1] = { 131 4, 3, 2, 2, 2, 2, 2, 2, 132 2, 2, 2, 2, 2, 1, 1, 1, 133 2, 2, 2, 2, 2, 2, 2, 2, 134 2, 3, 2, 1, 1, 1, 1, 1, 135 -1,-1,-1,-1 136 }; 137 #define LL_DEFAULTNORMLOG 6 /* for static allocation */ 138 static UNUSED_ATTR const U32 LL_defaultNormLog = LL_DEFAULTNORMLOG; 139 140 static UNUSED_ATTR const U8 ML_bits[MaxML+1] = { 141 0, 0, 0, 0, 0, 0, 0, 0, 142 0, 0, 0, 0, 0, 0, 0, 0, 143 0, 0, 0, 0, 0, 0, 0, 0, 144 0, 0, 0, 0, 0, 0, 0, 0, 145 1, 1, 1, 1, 2, 2, 3, 3, 146 4, 4, 5, 7, 8, 9,10,11, 147 12,13,14,15,16 148 }; 149 static UNUSED_ATTR const S16 ML_defaultNorm[MaxML+1] = { 150 1, 4, 3, 2, 2, 2, 2, 2, 151 2, 1, 1, 1, 1, 1, 1, 1, 152 1, 1, 1, 1, 1, 1, 1, 1, 153 1, 1, 1, 1, 1, 1, 1, 1, 154 1, 1, 1, 1, 1, 1, 1, 1, 155 1, 1, 1, 1, 1, 1,-1,-1, 156 -1,-1,-1,-1,-1 157 }; 158 #define ML_DEFAULTNORMLOG 6 /* for static allocation */ 159 static UNUSED_ATTR const U32 ML_defaultNormLog = ML_DEFAULTNORMLOG; 160 161 static UNUSED_ATTR const S16 OF_defaultNorm[DefaultMaxOff+1] = { 162 1, 1, 1, 1, 1, 1, 2, 2, 163 2, 1, 1, 1, 1, 1, 1, 1, 164 1, 1, 1, 1, 1, 1, 1, 1, 165 -1,-1,-1,-1,-1 166 }; 167 #define OF_DEFAULTNORMLOG 5 /* for static allocation */ 168 static UNUSED_ATTR const U32 OF_defaultNormLog = OF_DEFAULTNORMLOG; 169 170 171 /*-******************************************* 172 * Shared functions to include for inlining 173 *********************************************/ 174 static void ZSTD_copy8(void* dst, const void* src) { 175 #if defined(ZSTD_ARCH_ARM_NEON) 176 vst1_u8((uint8_t*)dst, vld1_u8((const uint8_t*)src)); 177 #else 178 ZSTD_memcpy(dst, src, 8); 179 #endif 180 } 181 #define COPY8(d,s) do { ZSTD_copy8(d,s); d+=8; s+=8; } while (0) 182 183 /* Need to use memmove here since the literal buffer can now be located within 184 the dst buffer. In circumstances where the op "catches up" to where the 185 literal buffer is, there can be partial overlaps in this call on the final 186 copy if the literal is being shifted by less than 16 bytes. */ 187 static void ZSTD_copy16(void* dst, const void* src) { 188 #if defined(ZSTD_ARCH_ARM_NEON) 189 vst1q_u8((uint8_t*)dst, vld1q_u8((const uint8_t*)src)); 190 #elif defined(ZSTD_ARCH_X86_SSE2) 191 _mm_storeu_si128((__m128i*)dst, _mm_loadu_si128((const __m128i*)src)); 192 #elif defined(__clang__) 193 ZSTD_memmove(dst, src, 16); 194 #else 195 /* ZSTD_memmove is not inlined properly by gcc */ 196 BYTE copy16_buf[16]; 197 ZSTD_memcpy(copy16_buf, src, 16); 198 ZSTD_memcpy(dst, copy16_buf, 16); 199 #endif 200 } 201 #define COPY16(d,s) do { ZSTD_copy16(d,s); d+=16; s+=16; } while (0) 202 203 #define WILDCOPY_OVERLENGTH 32 204 #define WILDCOPY_VECLEN 16 205 206 typedef enum { 207 ZSTD_no_overlap, 208 ZSTD_overlap_src_before_dst 209 /* ZSTD_overlap_dst_before_src, */ 210 } ZSTD_overlap_e; 211 212 /*! ZSTD_wildcopy() : 213 * Custom version of ZSTD_memcpy(), can over read/write up to WILDCOPY_OVERLENGTH bytes (if length==0) 214 * @param ovtype controls the overlap detection 215 * - ZSTD_no_overlap: The source and destination are guaranteed to be at least WILDCOPY_VECLEN bytes apart. 216 * - ZSTD_overlap_src_before_dst: The src and dst may overlap, but they MUST be at least 8 bytes apart. 217 * The src buffer must be before the dst buffer. 218 */ 219 MEM_STATIC FORCE_INLINE_ATTR 220 void ZSTD_wildcopy(void* dst, const void* src, ptrdiff_t length, ZSTD_overlap_e const ovtype) 221 { 222 ptrdiff_t diff = (BYTE*)dst - (const BYTE*)src; 223 const BYTE* ip = (const BYTE*)src; 224 BYTE* op = (BYTE*)dst; 225 BYTE* const oend = op + length; 226 227 if (ovtype == ZSTD_overlap_src_before_dst && diff < WILDCOPY_VECLEN) { 228 /* Handle short offset copies. */ 229 do { 230 COPY8(op, ip); 231 } while (op < oend); 232 } else { 233 assert(diff >= WILDCOPY_VECLEN || diff <= -WILDCOPY_VECLEN); 234 /* Separate out the first COPY16() call because the copy length is 235 * almost certain to be short, so the branches have different 236 * probabilities. Since it is almost certain to be short, only do 237 * one COPY16() in the first call. Then, do two calls per loop since 238 * at that point it is more likely to have a high trip count. 239 */ 240 ZSTD_copy16(op, ip); 241 if (16 >= length) return; 242 op += 16; 243 ip += 16; 244 do { 245 COPY16(op, ip); 246 COPY16(op, ip); 247 } 248 while (op < oend); 249 } 250 } 251 252 MEM_STATIC size_t ZSTD_limitCopy(void* dst, size_t dstCapacity, const void* src, size_t srcSize) 253 { 254 size_t const length = MIN(dstCapacity, srcSize); 255 if (length > 0) { 256 ZSTD_memcpy(dst, src, length); 257 } 258 return length; 259 } 260 261 /* define "workspace is too large" as this number of times larger than needed */ 262 #define ZSTD_WORKSPACETOOLARGE_FACTOR 3 263 264 /* when workspace is continuously too large 265 * during at least this number of times, 266 * context's memory usage is considered wasteful, 267 * because it's sized to handle a worst case scenario which rarely happens. 268 * In which case, resize it down to free some memory */ 269 #define ZSTD_WORKSPACETOOLARGE_MAXDURATION 128 270 271 /* Controls whether the input/output buffer is buffered or stable. */ 272 typedef enum { 273 ZSTD_bm_buffered = 0, /* Buffer the input/output */ 274 ZSTD_bm_stable = 1 /* ZSTD_inBuffer/ZSTD_outBuffer is stable */ 275 } ZSTD_bufferMode_e; 276 277 278 /*-******************************************* 279 * Private declarations 280 *********************************************/ 281 typedef struct seqDef_s { 282 U32 offBase; /* offBase == Offset + ZSTD_REP_NUM, or repcode 1,2,3 */ 283 U16 litLength; 284 U16 mlBase; /* mlBase == matchLength - MINMATCH */ 285 } seqDef; 286 287 /* Controls whether seqStore has a single "long" litLength or matchLength. See seqStore_t. */ 288 typedef enum { 289 ZSTD_llt_none = 0, /* no longLengthType */ 290 ZSTD_llt_literalLength = 1, /* represents a long literal */ 291 ZSTD_llt_matchLength = 2 /* represents a long match */ 292 } ZSTD_longLengthType_e; 293 294 typedef struct { 295 seqDef* sequencesStart; 296 seqDef* sequences; /* ptr to end of sequences */ 297 BYTE* litStart; 298 BYTE* lit; /* ptr to end of literals */ 299 BYTE* llCode; 300 BYTE* mlCode; 301 BYTE* ofCode; 302 size_t maxNbSeq; 303 size_t maxNbLit; 304 305 /* longLengthPos and longLengthType to allow us to represent either a single litLength or matchLength 306 * in the seqStore that has a value larger than U16 (if it exists). To do so, we increment 307 * the existing value of the litLength or matchLength by 0x10000. 308 */ 309 ZSTD_longLengthType_e longLengthType; 310 U32 longLengthPos; /* Index of the sequence to apply long length modification to */ 311 } seqStore_t; 312 313 typedef struct { 314 U32 litLength; 315 U32 matchLength; 316 } ZSTD_sequenceLength; 317 318 /** 319 * Returns the ZSTD_sequenceLength for the given sequences. It handles the decoding of long sequences 320 * indicated by longLengthPos and longLengthType, and adds MINMATCH back to matchLength. 321 */ 322 MEM_STATIC ZSTD_sequenceLength ZSTD_getSequenceLength(seqStore_t const* seqStore, seqDef const* seq) 323 { 324 ZSTD_sequenceLength seqLen; 325 seqLen.litLength = seq->litLength; 326 seqLen.matchLength = seq->mlBase + MINMATCH; 327 if (seqStore->longLengthPos == (U32)(seq - seqStore->sequencesStart)) { 328 if (seqStore->longLengthType == ZSTD_llt_literalLength) { 329 seqLen.litLength += 0x10000; 330 } 331 if (seqStore->longLengthType == ZSTD_llt_matchLength) { 332 seqLen.matchLength += 0x10000; 333 } 334 } 335 return seqLen; 336 } 337 338 /** 339 * Contains the compressed frame size and an upper-bound for the decompressed frame size. 340 * Note: before using `compressedSize`, check for errors using ZSTD_isError(). 341 * similarly, before using `decompressedBound`, check for errors using: 342 * `decompressedBound != ZSTD_CONTENTSIZE_ERROR` 343 */ 344 typedef struct { 345 size_t nbBlocks; 346 size_t compressedSize; 347 unsigned long long decompressedBound; 348 } ZSTD_frameSizeInfo; /* decompress & legacy */ 349 350 const seqStore_t* ZSTD_getSeqStore(const ZSTD_CCtx* ctx); /* compress & dictBuilder */ 351 int ZSTD_seqToCodes(const seqStore_t* seqStorePtr); /* compress, dictBuilder, decodeCorpus (shouldn't get its definition from here) */ 352 353 354 /* ZSTD_invalidateRepCodes() : 355 * ensures next compression will not use repcodes from previous block. 356 * Note : only works with regular variant; 357 * do not use with extDict variant ! */ 358 void ZSTD_invalidateRepCodes(ZSTD_CCtx* cctx); /* zstdmt, adaptive_compression (shouldn't get this definition from here) */ 359 360 361 typedef struct { 362 blockType_e blockType; 363 U32 lastBlock; 364 U32 origSize; 365 } blockProperties_t; /* declared here for decompress and fullbench */ 366 367 /*! ZSTD_getcBlockSize() : 368 * Provides the size of compressed block from block header `src` */ 369 /* Used by: decompress, fullbench */ 370 size_t ZSTD_getcBlockSize(const void* src, size_t srcSize, 371 blockProperties_t* bpPtr); 372 373 /*! ZSTD_decodeSeqHeaders() : 374 * decode sequence header from src */ 375 /* Used by: zstd_decompress_block, fullbench */ 376 size_t ZSTD_decodeSeqHeaders(ZSTD_DCtx* dctx, int* nbSeqPtr, 377 const void* src, size_t srcSize); 378 379 /** 380 * @returns true iff the CPU supports dynamic BMI2 dispatch. 381 */ 382 MEM_STATIC int ZSTD_cpuSupportsBmi2(void) 383 { 384 ZSTD_cpuid_t cpuid = ZSTD_cpuid(); 385 return ZSTD_cpuid_bmi1(cpuid) && ZSTD_cpuid_bmi2(cpuid); 386 } 387 388 #if defined (__cplusplus) 389 } 390 #endif 391 392 #endif /* ZSTD_CCOMMON_H_MODULE */ 393