diff options
Diffstat (limited to 'lib/zstd/common/zstd_internal.h')
-rw-r--r-- | lib/zstd/common/zstd_internal.h | 443 |
1 files changed, 443 insertions, 0 deletions
diff --git a/lib/zstd/common/zstd_internal.h b/lib/zstd/common/zstd_internal.h new file mode 100644 index 0000000000..93305d9b41 --- /dev/null +++ b/lib/zstd/common/zstd_internal.h @@ -0,0 +1,443 @@ +/* + * Copyright (c) Yann Collet, Facebook, Inc. + * All rights reserved. + * + * This source code is licensed under both the BSD-style license (found in the + * LICENSE file in the root directory of this source tree) and the GPLv2 (found + * in the COPYING file in the root directory of this source tree). + * You may select, at your option, one of the above-listed licenses. + */ + +#ifndef ZSTD_CCOMMON_H_MODULE +#define ZSTD_CCOMMON_H_MODULE + +/* this module contains definitions which must be identical + * across compression, decompression and dictBuilder. + * It also contains a few functions useful to at least 2 of them + * and which benefit from being inlined */ + +/*-************************************* +* Dependencies +***************************************/ +#include "compiler.h" +#include "cpu.h" +#include "mem.h" +#include "debug.h" /* assert, DEBUGLOG, RAWLOG, g_debuglevel */ +#include "error_private.h" +#define ZSTD_STATIC_LINKING_ONLY +#include <linux/zstd.h> +#define FSE_STATIC_LINKING_ONLY +#include "fse.h" +#define HUF_STATIC_LINKING_ONLY +#include "huf.h" +#include <linux/xxhash.h> /* XXH_reset, update, digest */ +#define ZSTD_TRACE 0 + + +/* ---- static assert (debug) --- */ +#define ZSTD_STATIC_ASSERT(c) DEBUG_STATIC_ASSERT(c) +#define ZSTD_isError ERR_isError /* for inlining */ +#define FSE_isError ERR_isError +#define HUF_isError ERR_isError + + +/*-************************************* +* shared macros +***************************************/ +#undef MIN +#undef MAX +#define MIN(a,b) ((a)<(b) ? (a) : (b)) +#define MAX(a,b) ((a)>(b) ? (a) : (b)) +#define BOUNDED(min,val,max) (MAX(min,MIN(val,max))) + + +/*-************************************* +* Common constants +***************************************/ +#define ZSTD_OPT_NUM (1<<12) + +#define ZSTD_REP_NUM 3 /* number of repcodes */ +static UNUSED_ATTR const U32 repStartValue[ZSTD_REP_NUM] = { 1, 4, 8 }; + +#define KB *(1 <<10) +#define MB *(1 <<20) +#define GB *(1U<<30) + +#define BIT7 128 +#define BIT6 64 +#define BIT5 32 +#define BIT4 16 +#define BIT1 2 +#define BIT0 1 + +#define ZSTD_WINDOWLOG_ABSOLUTEMIN 10 +static UNUSED_ATTR const size_t ZSTD_fcs_fieldSize[4] = { 0, 2, 4, 8 }; +static UNUSED_ATTR const size_t ZSTD_did_fieldSize[4] = { 0, 1, 2, 4 }; + +#define ZSTD_FRAMEIDSIZE 4 /* magic number size */ + +#define ZSTD_BLOCKHEADERSIZE 3 /* C standard doesn't allow `static const` variable to be init using another `static const` variable */ +static UNUSED_ATTR const size_t ZSTD_blockHeaderSize = ZSTD_BLOCKHEADERSIZE; +typedef enum { bt_raw, bt_rle, bt_compressed, bt_reserved } blockType_e; + +#define ZSTD_FRAMECHECKSUMSIZE 4 + +#define MIN_SEQUENCES_SIZE 1 /* nbSeq==0 */ +#define MIN_CBLOCK_SIZE (1 /*litCSize*/ + 1 /* RLE or RAW */ + MIN_SEQUENCES_SIZE /* nbSeq==0 */) /* for a non-null block */ + +#define HufLog 12 +typedef enum { set_basic, set_rle, set_compressed, set_repeat } symbolEncodingType_e; + +#define LONGNBSEQ 0x7F00 + +#define MINMATCH 3 + +#define Litbits 8 +#define MaxLit ((1<<Litbits) - 1) +#define MaxML 52 +#define MaxLL 35 +#define DefaultMaxOff 28 +#define MaxOff 31 +#define MaxSeq MAX(MaxLL, MaxML) /* Assumption : MaxOff < MaxLL,MaxML */ +#define MLFSELog 9 +#define LLFSELog 9 +#define OffFSELog 8 +#define MaxFSELog MAX(MAX(MLFSELog, LLFSELog), OffFSELog) + +#define ZSTD_MAX_HUF_HEADER_SIZE 128 /* header + <= 127 byte tree description */ +/* Each table cannot take more than #symbols * FSELog bits */ +#define ZSTD_MAX_FSE_HEADERS_SIZE (((MaxML + 1) * MLFSELog + (MaxLL + 1) * LLFSELog + (MaxOff + 1) * OffFSELog + 7) / 8) + +static UNUSED_ATTR const U8 LL_bits[MaxLL+1] = { + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, + 1, 1, 1, 1, 2, 2, 3, 3, + 4, 6, 7, 8, 9,10,11,12, + 13,14,15,16 +}; +static UNUSED_ATTR const S16 LL_defaultNorm[MaxLL+1] = { + 4, 3, 2, 2, 2, 2, 2, 2, + 2, 2, 2, 2, 2, 1, 1, 1, + 2, 2, 2, 2, 2, 2, 2, 2, + 2, 3, 2, 1, 1, 1, 1, 1, + -1,-1,-1,-1 +}; +#define LL_DEFAULTNORMLOG 6 /* for static allocation */ +static UNUSED_ATTR const U32 LL_defaultNormLog = LL_DEFAULTNORMLOG; + +static UNUSED_ATTR const U8 ML_bits[MaxML+1] = { + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, + 1, 1, 1, 1, 2, 2, 3, 3, + 4, 4, 5, 7, 8, 9,10,11, + 12,13,14,15,16 +}; +static UNUSED_ATTR const S16 ML_defaultNorm[MaxML+1] = { + 1, 4, 3, 2, 2, 2, 2, 2, + 2, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1,-1,-1, + -1,-1,-1,-1,-1 +}; +#define ML_DEFAULTNORMLOG 6 /* for static allocation */ +static UNUSED_ATTR const U32 ML_defaultNormLog = ML_DEFAULTNORMLOG; + +static UNUSED_ATTR const S16 OF_defaultNorm[DefaultMaxOff+1] = { + 1, 1, 1, 1, 1, 1, 2, 2, + 2, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, + -1,-1,-1,-1,-1 +}; +#define OF_DEFAULTNORMLOG 5 /* for static allocation */ +static UNUSED_ATTR const U32 OF_defaultNormLog = OF_DEFAULTNORMLOG; + + +/*-******************************************* +* Shared functions to include for inlining +*********************************************/ +static void ZSTD_copy8(void* dst, const void* src) { +#if defined(ZSTD_ARCH_ARM_NEON) + vst1_u8((uint8_t*)dst, vld1_u8((const uint8_t*)src)); +#else + ZSTD_memcpy(dst, src, 8); +#endif +} +#define COPY8(d,s) { ZSTD_copy8(d,s); d+=8; s+=8; } + +/* Need to use memmove here since the literal buffer can now be located within + the dst buffer. In circumstances where the op "catches up" to where the + literal buffer is, there can be partial overlaps in this call on the final + copy if the literal is being shifted by less than 16 bytes. */ +static void ZSTD_copy16(void* dst, const void* src) { +#if defined(ZSTD_ARCH_ARM_NEON) + vst1q_u8((uint8_t*)dst, vld1q_u8((const uint8_t*)src)); +#elif defined(ZSTD_ARCH_X86_SSE2) + _mm_storeu_si128((__m128i*)dst, _mm_loadu_si128((const __m128i*)src)); +#elif defined(__clang__) + ZSTD_memmove(dst, src, 16); +#else + /* ZSTD_memmove is not inlined properly by gcc */ + BYTE copy16_buf[16]; + ZSTD_memcpy(copy16_buf, src, 16); + ZSTD_memcpy(dst, copy16_buf, 16); +#endif +} +#define COPY16(d,s) { ZSTD_copy16(d,s); d+=16; s+=16; } + +#define WILDCOPY_OVERLENGTH 32 +#define WILDCOPY_VECLEN 16 + +typedef enum { + ZSTD_no_overlap, + ZSTD_overlap_src_before_dst + /* ZSTD_overlap_dst_before_src, */ +} ZSTD_overlap_e; + +/*! ZSTD_wildcopy() : + * Custom version of ZSTD_memcpy(), can over read/write up to WILDCOPY_OVERLENGTH bytes (if length==0) + * @param ovtype controls the overlap detection + * - ZSTD_no_overlap: The source and destination are guaranteed to be at least WILDCOPY_VECLEN bytes apart. + * - ZSTD_overlap_src_before_dst: The src and dst may overlap, but they MUST be at least 8 bytes apart. + * The src buffer must be before the dst buffer. + */ +MEM_STATIC FORCE_INLINE_ATTR +void ZSTD_wildcopy(void* dst, const void* src, ptrdiff_t length, ZSTD_overlap_e const ovtype) +{ + ptrdiff_t diff = (BYTE*)dst - (const BYTE*)src; + const BYTE* ip = (const BYTE*)src; + BYTE* op = (BYTE*)dst; + BYTE* const oend = op + length; + + if (ovtype == ZSTD_overlap_src_before_dst && diff < WILDCOPY_VECLEN) { + /* Handle short offset copies. */ + do { + COPY8(op, ip) + } while (op < oend); + } else { + assert(diff >= WILDCOPY_VECLEN || diff <= -WILDCOPY_VECLEN); + /* Separate out the first COPY16() call because the copy length is + * almost certain to be short, so the branches have different + * probabilities. Since it is almost certain to be short, only do + * one COPY16() in the first call. Then, do two calls per loop since + * at that point it is more likely to have a high trip count. + */ +#ifdef __aarch64__ + do { + COPY16(op, ip); + } + while (op < oend); +#else + ZSTD_copy16(op, ip); + if (16 >= length) return; + op += 16; + ip += 16; + do { + COPY16(op, ip); + COPY16(op, ip); + } + while (op < oend); +#endif + } +} + +MEM_STATIC size_t ZSTD_limitCopy(void* dst, size_t dstCapacity, const void* src, size_t srcSize) +{ + size_t const length = MIN(dstCapacity, srcSize); + if (length > 0) { + ZSTD_memcpy(dst, src, length); + } + return length; +} + +/* define "workspace is too large" as this number of times larger than needed */ +#define ZSTD_WORKSPACETOOLARGE_FACTOR 3 + +/* when workspace is continuously too large + * during at least this number of times, + * context's memory usage is considered wasteful, + * because it's sized to handle a worst case scenario which rarely happens. + * In which case, resize it down to free some memory */ +#define ZSTD_WORKSPACETOOLARGE_MAXDURATION 128 + +/* Controls whether the input/output buffer is buffered or stable. */ +typedef enum { + ZSTD_bm_buffered = 0, /* Buffer the input/output */ + ZSTD_bm_stable = 1 /* ZSTD_inBuffer/ZSTD_outBuffer is stable */ +} ZSTD_bufferMode_e; + + +/*-******************************************* +* Private declarations +*********************************************/ +typedef struct seqDef_s { + U32 offBase; /* offBase == Offset + ZSTD_REP_NUM, or repcode 1,2,3 */ + U16 litLength; + U16 mlBase; /* mlBase == matchLength - MINMATCH */ +} seqDef; + +/* Controls whether seqStore has a single "long" litLength or matchLength. See seqStore_t. */ +typedef enum { + ZSTD_llt_none = 0, /* no longLengthType */ + ZSTD_llt_literalLength = 1, /* represents a long literal */ + ZSTD_llt_matchLength = 2 /* represents a long match */ +} ZSTD_longLengthType_e; + +typedef struct { + seqDef* sequencesStart; + seqDef* sequences; /* ptr to end of sequences */ + BYTE* litStart; + BYTE* lit; /* ptr to end of literals */ + BYTE* llCode; + BYTE* mlCode; + BYTE* ofCode; + size_t maxNbSeq; + size_t maxNbLit; + + /* longLengthPos and longLengthType to allow us to represent either a single litLength or matchLength + * in the seqStore that has a value larger than U16 (if it exists). To do so, we increment + * the existing value of the litLength or matchLength by 0x10000. + */ + ZSTD_longLengthType_e longLengthType; + U32 longLengthPos; /* Index of the sequence to apply long length modification to */ +} seqStore_t; + +typedef struct { + U32 litLength; + U32 matchLength; +} ZSTD_sequenceLength; + +/* + * Returns the ZSTD_sequenceLength for the given sequences. It handles the decoding of long sequences + * indicated by longLengthPos and longLengthType, and adds MINMATCH back to matchLength. + */ +MEM_STATIC ZSTD_sequenceLength ZSTD_getSequenceLength(seqStore_t const* seqStore, seqDef const* seq) +{ + ZSTD_sequenceLength seqLen; + seqLen.litLength = seq->litLength; + seqLen.matchLength = seq->mlBase + MINMATCH; + if (seqStore->longLengthPos == (U32)(seq - seqStore->sequencesStart)) { + if (seqStore->longLengthType == ZSTD_llt_literalLength) { + seqLen.litLength += 0xFFFF; + } + if (seqStore->longLengthType == ZSTD_llt_matchLength) { + seqLen.matchLength += 0xFFFF; + } + } + return seqLen; +} + +/* + * Contains the compressed frame size and an upper-bound for the decompressed frame size. + * Note: before using `compressedSize`, check for errors using ZSTD_isError(). + * similarly, before using `decompressedBound`, check for errors using: + * `decompressedBound != ZSTD_CONTENTSIZE_ERROR` + */ +typedef struct { + size_t compressedSize; + unsigned long long decompressedBound; +} ZSTD_frameSizeInfo; /* decompress & legacy */ + +const seqStore_t* ZSTD_getSeqStore(const ZSTD_CCtx* ctx); /* compress & dictBuilder */ +void ZSTD_seqToCodes(const seqStore_t* seqStorePtr); /* compress, dictBuilder, decodeCorpus (shouldn't get its definition from here) */ + +/* custom memory allocation functions */ +void* ZSTD_customMalloc(size_t size, ZSTD_customMem customMem); +void* ZSTD_customCalloc(size_t size, ZSTD_customMem customMem); +void ZSTD_customFree(void* ptr, ZSTD_customMem customMem); + + +MEM_STATIC U32 ZSTD_highbit32(U32 val) /* compress, dictBuilder, decodeCorpus */ +{ + assert(val != 0); + { +# if (__GNUC__ >= 3) /* GCC Intrinsic */ + return __builtin_clz (val) ^ 31; +# else /* Software version */ + static const U32 DeBruijnClz[32] = { 0, 9, 1, 10, 13, 21, 2, 29, 11, 14, 16, 18, 22, 25, 3, 30, 8, 12, 20, 28, 15, 17, 24, 7, 19, 27, 23, 6, 26, 5, 4, 31 }; + U32 v = val; + v |= v >> 1; + v |= v >> 2; + v |= v >> 4; + v |= v >> 8; + v |= v >> 16; + return DeBruijnClz[(v * 0x07C4ACDDU) >> 27]; +# endif + } +} + +/* + * Counts the number of trailing zeros of a `size_t`. + * Most compilers should support CTZ as a builtin. A backup + * implementation is provided if the builtin isn't supported, but + * it may not be terribly efficient. + */ +MEM_STATIC unsigned ZSTD_countTrailingZeros(size_t val) +{ + if (MEM_64bits()) { +# if (__GNUC__ >= 4) + return __builtin_ctzll((U64)val); +# else + static const int DeBruijnBytePos[64] = { 0, 1, 2, 7, 3, 13, 8, 19, + 4, 25, 14, 28, 9, 34, 20, 56, + 5, 17, 26, 54, 15, 41, 29, 43, + 10, 31, 38, 35, 21, 45, 49, 57, + 63, 6, 12, 18, 24, 27, 33, 55, + 16, 53, 40, 42, 30, 37, 44, 48, + 62, 11, 23, 32, 52, 39, 36, 47, + 61, 22, 51, 46, 60, 50, 59, 58 }; + return DeBruijnBytePos[((U64)((val & -(long long)val) * 0x0218A392CDABBD3FULL)) >> 58]; +# endif + } else { /* 32 bits */ +# if (__GNUC__ >= 3) + return __builtin_ctz((U32)val); +# else + static const int DeBruijnBytePos[32] = { 0, 1, 28, 2, 29, 14, 24, 3, + 30, 22, 20, 15, 25, 17, 4, 8, + 31, 27, 13, 23, 21, 19, 16, 7, + 26, 12, 18, 6, 11, 5, 10, 9 }; + return DeBruijnBytePos[((U32)((val & -(S32)val) * 0x077CB531U)) >> 27]; +# endif + } +} + + +/* ZSTD_invalidateRepCodes() : + * ensures next compression will not use repcodes from previous block. + * Note : only works with regular variant; + * do not use with extDict variant ! */ +void ZSTD_invalidateRepCodes(ZSTD_CCtx* cctx); /* zstdmt, adaptive_compression (shouldn't get this definition from here) */ + + +typedef struct { + blockType_e blockType; + U32 lastBlock; + U32 origSize; +} blockProperties_t; /* declared here for decompress and fullbench */ + +/*! ZSTD_getcBlockSize() : + * Provides the size of compressed block from block header `src` */ +/* Used by: decompress, fullbench (does not get its definition from here) */ +size_t ZSTD_getcBlockSize(const void* src, size_t srcSize, + blockProperties_t* bpPtr); + +/*! ZSTD_decodeSeqHeaders() : + * decode sequence header from src */ +/* Used by: decompress, fullbench (does not get its definition from here) */ +size_t ZSTD_decodeSeqHeaders(ZSTD_DCtx* dctx, int* nbSeqPtr, + const void* src, size_t srcSize); + +/* + * @returns true iff the CPU supports dynamic BMI2 dispatch. + */ +MEM_STATIC int ZSTD_cpuSupportsBmi2(void) +{ + ZSTD_cpuid_t cpuid = ZSTD_cpuid(); + return ZSTD_cpuid_bmi1(cpuid) && ZSTD_cpuid_bmi2(cpuid); +} + + +#endif /* ZSTD_CCOMMON_H_MODULE */ |