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-rw-r--r--lib/zstd/decompress/huf_decompress.c912
-rw-r--r--lib/zstd/decompress/zstd_decompress.c80
-rw-r--r--lib/zstd/decompress/zstd_decompress_block.c1022
-rw-r--r--lib/zstd/decompress/zstd_decompress_block.h10
-rw-r--r--lib/zstd/decompress/zstd_decompress_internal.h38
5 files changed, 1603 insertions, 459 deletions
diff --git a/lib/zstd/decompress/huf_decompress.c b/lib/zstd/decompress/huf_decompress.c
index 5105e59ac04a..89b269a641c7 100644
--- a/lib/zstd/decompress/huf_decompress.c
+++ b/lib/zstd/decompress/huf_decompress.c
@@ -22,6 +22,13 @@
#define HUF_STATIC_LINKING_ONLY
#include "../common/huf.h"
#include "../common/error_private.h"
+#include "../common/zstd_internal.h"
+
+/* **************************************************************
+* Constants
+****************************************************************/
+
+#define HUF_DECODER_FAST_TABLELOG 11
/* **************************************************************
* Macros
@@ -36,6 +43,26 @@
#error "Cannot force the use of the X1 and X2 decoders at the same time!"
#endif
+#if ZSTD_ENABLE_ASM_X86_64_BMI2 && DYNAMIC_BMI2
+# define HUF_ASM_X86_64_BMI2_ATTRS BMI2_TARGET_ATTRIBUTE
+#else
+# define HUF_ASM_X86_64_BMI2_ATTRS
+#endif
+
+#define HUF_EXTERN_C
+#define HUF_ASM_DECL HUF_EXTERN_C
+
+#if DYNAMIC_BMI2 || (ZSTD_ENABLE_ASM_X86_64_BMI2 && defined(__BMI2__))
+# define HUF_NEED_BMI2_FUNCTION 1
+#else
+# define HUF_NEED_BMI2_FUNCTION 0
+#endif
+
+#if !(ZSTD_ENABLE_ASM_X86_64_BMI2 && defined(__BMI2__))
+# define HUF_NEED_DEFAULT_FUNCTION 1
+#else
+# define HUF_NEED_DEFAULT_FUNCTION 0
+#endif
/* **************************************************************
* Error Management
@@ -65,7 +92,7 @@
return fn##_body(dst, dstSize, cSrc, cSrcSize, DTable); \
} \
\
- static TARGET_ATTRIBUTE("bmi2") size_t fn##_bmi2( \
+ static BMI2_TARGET_ATTRIBUTE size_t fn##_bmi2( \
void* dst, size_t dstSize, \
const void* cSrc, size_t cSrcSize, \
const HUF_DTable* DTable) \
@@ -107,13 +134,147 @@ static DTableDesc HUF_getDTableDesc(const HUF_DTable* table)
return dtd;
}
+#if ZSTD_ENABLE_ASM_X86_64_BMI2
+
+static size_t HUF_initDStream(BYTE const* ip) {
+ BYTE const lastByte = ip[7];
+ size_t const bitsConsumed = lastByte ? 8 - BIT_highbit32(lastByte) : 0;
+ size_t const value = MEM_readLEST(ip) | 1;
+ assert(bitsConsumed <= 8);
+ return value << bitsConsumed;
+}
+typedef struct {
+ BYTE const* ip[4];
+ BYTE* op[4];
+ U64 bits[4];
+ void const* dt;
+ BYTE const* ilimit;
+ BYTE* oend;
+ BYTE const* iend[4];
+} HUF_DecompressAsmArgs;
+
+/*
+ * Initializes args for the asm decoding loop.
+ * @returns 0 on success
+ * 1 if the fallback implementation should be used.
+ * Or an error code on failure.
+ */
+static size_t HUF_DecompressAsmArgs_init(HUF_DecompressAsmArgs* args, void* dst, size_t dstSize, void const* src, size_t srcSize, const HUF_DTable* DTable)
+{
+ void const* dt = DTable + 1;
+ U32 const dtLog = HUF_getDTableDesc(DTable).tableLog;
+
+ const BYTE* const ilimit = (const BYTE*)src + 6 + 8;
+
+ BYTE* const oend = (BYTE*)dst + dstSize;
+
+ /* The following condition is false on x32 platform,
+ * but HUF_asm is not compatible with this ABI */
+ if (!(MEM_isLittleEndian() && !MEM_32bits())) return 1;
+
+ /* strict minimum : jump table + 1 byte per stream */
+ if (srcSize < 10)
+ return ERROR(corruption_detected);
+
+ /* Must have at least 8 bytes per stream because we don't handle initializing smaller bit containers.
+ * If table log is not correct at this point, fallback to the old decoder.
+ * On small inputs we don't have enough data to trigger the fast loop, so use the old decoder.
+ */
+ if (dtLog != HUF_DECODER_FAST_TABLELOG)
+ return 1;
+
+ /* Read the jump table. */
+ {
+ const BYTE* const istart = (const BYTE*)src;
+ size_t const length1 = MEM_readLE16(istart);
+ size_t const length2 = MEM_readLE16(istart+2);
+ size_t const length3 = MEM_readLE16(istart+4);
+ size_t const length4 = srcSize - (length1 + length2 + length3 + 6);
+ args->iend[0] = istart + 6; /* jumpTable */
+ args->iend[1] = args->iend[0] + length1;
+ args->iend[2] = args->iend[1] + length2;
+ args->iend[3] = args->iend[2] + length3;
+
+ /* HUF_initDStream() requires this, and this small of an input
+ * won't benefit from the ASM loop anyways.
+ * length1 must be >= 16 so that ip[0] >= ilimit before the loop
+ * starts.
+ */
+ if (length1 < 16 || length2 < 8 || length3 < 8 || length4 < 8)
+ return 1;
+ if (length4 > srcSize) return ERROR(corruption_detected); /* overflow */
+ }
+ /* ip[] contains the position that is currently loaded into bits[]. */
+ args->ip[0] = args->iend[1] - sizeof(U64);
+ args->ip[1] = args->iend[2] - sizeof(U64);
+ args->ip[2] = args->iend[3] - sizeof(U64);
+ args->ip[3] = (BYTE const*)src + srcSize - sizeof(U64);
+
+ /* op[] contains the output pointers. */
+ args->op[0] = (BYTE*)dst;
+ args->op[1] = args->op[0] + (dstSize+3)/4;
+ args->op[2] = args->op[1] + (dstSize+3)/4;
+ args->op[3] = args->op[2] + (dstSize+3)/4;
+
+ /* No point to call the ASM loop for tiny outputs. */
+ if (args->op[3] >= oend)
+ return 1;
+
+ /* bits[] is the bit container.
+ * It is read from the MSB down to the LSB.
+ * It is shifted left as it is read, and zeros are
+ * shifted in. After the lowest valid bit a 1 is
+ * set, so that CountTrailingZeros(bits[]) can be used
+ * to count how many bits we've consumed.
+ */
+ args->bits[0] = HUF_initDStream(args->ip[0]);
+ args->bits[1] = HUF_initDStream(args->ip[1]);
+ args->bits[2] = HUF_initDStream(args->ip[2]);
+ args->bits[3] = HUF_initDStream(args->ip[3]);
+
+ /* If ip[] >= ilimit, it is guaranteed to be safe to
+ * reload bits[]. It may be beyond its section, but is
+ * guaranteed to be valid (>= istart).
+ */
+ args->ilimit = ilimit;
+
+ args->oend = oend;
+ args->dt = dt;
+
+ return 0;
+}
+
+static size_t HUF_initRemainingDStream(BIT_DStream_t* bit, HUF_DecompressAsmArgs const* args, int stream, BYTE* segmentEnd)
+{
+ /* Validate that we haven't overwritten. */
+ if (args->op[stream] > segmentEnd)
+ return ERROR(corruption_detected);
+ /* Validate that we haven't read beyond iend[].
+ * Note that ip[] may be < iend[] because the MSB is
+ * the next bit to read, and we may have consumed 100%
+ * of the stream, so down to iend[i] - 8 is valid.
+ */
+ if (args->ip[stream] < args->iend[stream] - 8)
+ return ERROR(corruption_detected);
+
+ /* Construct the BIT_DStream_t. */
+ bit->bitContainer = MEM_readLE64(args->ip[stream]);
+ bit->bitsConsumed = ZSTD_countTrailingZeros((size_t)args->bits[stream]);
+ bit->start = (const char*)args->iend[0];
+ bit->limitPtr = bit->start + sizeof(size_t);
+ bit->ptr = (const char*)args->ip[stream];
+
+ return 0;
+}
+#endif
+
#ifndef HUF_FORCE_DECOMPRESS_X2
/*-***************************/
/* single-symbol decoding */
/*-***************************/
-typedef struct { BYTE byte; BYTE nbBits; } HUF_DEltX1; /* single-symbol decoding */
+typedef struct { BYTE nbBits; BYTE byte; } HUF_DEltX1; /* single-symbol decoding */
/*
* Packs 4 HUF_DEltX1 structs into a U64. This is used to lay down 4 entries at
@@ -122,14 +283,44 @@ typedef struct { BYTE byte; BYTE nbBits; } HUF_DEltX1; /* single-symbol decodi
static U64 HUF_DEltX1_set4(BYTE symbol, BYTE nbBits) {
U64 D4;
if (MEM_isLittleEndian()) {
- D4 = symbol + (nbBits << 8);
- } else {
D4 = (symbol << 8) + nbBits;
+ } else {
+ D4 = symbol + (nbBits << 8);
}
D4 *= 0x0001000100010001ULL;
return D4;
}
+/*
+ * Increase the tableLog to targetTableLog and rescales the stats.
+ * If tableLog > targetTableLog this is a no-op.
+ * @returns New tableLog
+ */
+static U32 HUF_rescaleStats(BYTE* huffWeight, U32* rankVal, U32 nbSymbols, U32 tableLog, U32 targetTableLog)
+{
+ if (tableLog > targetTableLog)
+ return tableLog;
+ if (tableLog < targetTableLog) {
+ U32 const scale = targetTableLog - tableLog;
+ U32 s;
+ /* Increase the weight for all non-zero probability symbols by scale. */
+ for (s = 0; s < nbSymbols; ++s) {
+ huffWeight[s] += (BYTE)((huffWeight[s] == 0) ? 0 : scale);
+ }
+ /* Update rankVal to reflect the new weights.
+ * All weights except 0 get moved to weight + scale.
+ * Weights [1, scale] are empty.
+ */
+ for (s = targetTableLog; s > scale; --s) {
+ rankVal[s] = rankVal[s - scale];
+ }
+ for (s = scale; s > 0; --s) {
+ rankVal[s] = 0;
+ }
+ }
+ return targetTableLog;
+}
+
typedef struct {
U32 rankVal[HUF_TABLELOG_ABSOLUTEMAX + 1];
U32 rankStart[HUF_TABLELOG_ABSOLUTEMAX + 1];
@@ -162,8 +353,12 @@ size_t HUF_readDTableX1_wksp_bmi2(HUF_DTable* DTable, const void* src, size_t sr
iSize = HUF_readStats_wksp(wksp->huffWeight, HUF_SYMBOLVALUE_MAX + 1, wksp->rankVal, &nbSymbols, &tableLog, src, srcSize, wksp->statsWksp, sizeof(wksp->statsWksp), bmi2);
if (HUF_isError(iSize)) return iSize;
+
/* Table header */
{ DTableDesc dtd = HUF_getDTableDesc(DTable);
+ U32 const maxTableLog = dtd.maxTableLog + 1;
+ U32 const targetTableLog = MIN(maxTableLog, HUF_DECODER_FAST_TABLELOG);
+ tableLog = HUF_rescaleStats(wksp->huffWeight, wksp->rankVal, nbSymbols, tableLog, targetTableLog);
if (tableLog > (U32)(dtd.maxTableLog+1)) return ERROR(tableLog_tooLarge); /* DTable too small, Huffman tree cannot fit in */
dtd.tableType = 0;
dtd.tableLog = (BYTE)tableLog;
@@ -207,7 +402,7 @@ size_t HUF_readDTableX1_wksp_bmi2(HUF_DTable* DTable, const void* src, size_t sr
/* fill DTable
* We fill all entries of each weight in order.
- * That way length is a constant for each iteration of the outter loop.
+ * That way length is a constant for each iteration of the outer loop.
* We can switch based on the length to a different inner loop which is
* optimized for that particular case.
*/
@@ -304,11 +499,15 @@ HUF_decodeStreamX1(BYTE* p, BIT_DStream_t* const bitDPtr, BYTE* const pEnd, cons
BYTE* const pStart = p;
/* up to 4 symbols at a time */
- while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p < pEnd-3)) {
- HUF_DECODE_SYMBOLX1_2(p, bitDPtr);
- HUF_DECODE_SYMBOLX1_1(p, bitDPtr);
- HUF_DECODE_SYMBOLX1_2(p, bitDPtr);
- HUF_DECODE_SYMBOLX1_0(p, bitDPtr);
+ if ((pEnd - p) > 3) {
+ while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p < pEnd-3)) {
+ HUF_DECODE_SYMBOLX1_2(p, bitDPtr);
+ HUF_DECODE_SYMBOLX1_1(p, bitDPtr);
+ HUF_DECODE_SYMBOLX1_2(p, bitDPtr);
+ HUF_DECODE_SYMBOLX1_0(p, bitDPtr);
+ }
+ } else {
+ BIT_reloadDStream(bitDPtr);
}
/* [0-3] symbols remaining */
@@ -388,33 +587,36 @@ HUF_decompress4X1_usingDTable_internal_body(
U32 endSignal = 1;
if (length4 > cSrcSize) return ERROR(corruption_detected); /* overflow */
+ if (opStart4 > oend) return ERROR(corruption_detected); /* overflow */
CHECK_F( BIT_initDStream(&bitD1, istart1, length1) );
CHECK_F( BIT_initDStream(&bitD2, istart2, length2) );
CHECK_F( BIT_initDStream(&bitD3, istart3, length3) );
CHECK_F( BIT_initDStream(&bitD4, istart4, length4) );
/* up to 16 symbols per loop (4 symbols per stream) in 64-bit mode */
- for ( ; (endSignal) & (op4 < olimit) ; ) {
- HUF_DECODE_SYMBOLX1_2(op1, &bitD1);
- HUF_DECODE_SYMBOLX1_2(op2, &bitD2);
- HUF_DECODE_SYMBOLX1_2(op3, &bitD3);
- HUF_DECODE_SYMBOLX1_2(op4, &bitD4);
- HUF_DECODE_SYMBOLX1_1(op1, &bitD1);
- HUF_DECODE_SYMBOLX1_1(op2, &bitD2);
- HUF_DECODE_SYMBOLX1_1(op3, &bitD3);
- HUF_DECODE_SYMBOLX1_1(op4, &bitD4);
- HUF_DECODE_SYMBOLX1_2(op1, &bitD1);
- HUF_DECODE_SYMBOLX1_2(op2, &bitD2);
- HUF_DECODE_SYMBOLX1_2(op3, &bitD3);
- HUF_DECODE_SYMBOLX1_2(op4, &bitD4);
- HUF_DECODE_SYMBOLX1_0(op1, &bitD1);
- HUF_DECODE_SYMBOLX1_0(op2, &bitD2);
- HUF_DECODE_SYMBOLX1_0(op3, &bitD3);
- HUF_DECODE_SYMBOLX1_0(op4, &bitD4);
- endSignal &= BIT_reloadDStreamFast(&bitD1) == BIT_DStream_unfinished;
- endSignal &= BIT_reloadDStreamFast(&bitD2) == BIT_DStream_unfinished;
- endSignal &= BIT_reloadDStreamFast(&bitD3) == BIT_DStream_unfinished;
- endSignal &= BIT_reloadDStreamFast(&bitD4) == BIT_DStream_unfinished;
+ if ((size_t)(oend - op4) >= sizeof(size_t)) {
+ for ( ; (endSignal) & (op4 < olimit) ; ) {
+ HUF_DECODE_SYMBOLX1_2(op1, &bitD1);
+ HUF_DECODE_SYMBOLX1_2(op2, &bitD2);
+ HUF_DECODE_SYMBOLX1_2(op3, &bitD3);
+ HUF_DECODE_SYMBOLX1_2(op4, &bitD4);
+ HUF_DECODE_SYMBOLX1_1(op1, &bitD1);
+ HUF_DECODE_SYMBOLX1_1(op2, &bitD2);
+ HUF_DECODE_SYMBOLX1_1(op3, &bitD3);
+ HUF_DECODE_SYMBOLX1_1(op4, &bitD4);
+ HUF_DECODE_SYMBOLX1_2(op1, &bitD1);
+ HUF_DECODE_SYMBOLX1_2(op2, &bitD2);
+ HUF_DECODE_SYMBOLX1_2(op3, &bitD3);
+ HUF_DECODE_SYMBOLX1_2(op4, &bitD4);
+ HUF_DECODE_SYMBOLX1_0(op1, &bitD1);
+ HUF_DECODE_SYMBOLX1_0(op2, &bitD2);
+ HUF_DECODE_SYMBOLX1_0(op3, &bitD3);
+ HUF_DECODE_SYMBOLX1_0(op4, &bitD4);
+ endSignal &= BIT_reloadDStreamFast(&bitD1) == BIT_DStream_unfinished;
+ endSignal &= BIT_reloadDStreamFast(&bitD2) == BIT_DStream_unfinished;
+ endSignal &= BIT_reloadDStreamFast(&bitD3) == BIT_DStream_unfinished;
+ endSignal &= BIT_reloadDStreamFast(&bitD4) == BIT_DStream_unfinished;
+ }
}
/* check corruption */
@@ -440,6 +642,79 @@ HUF_decompress4X1_usingDTable_internal_body(
}
}
+#if HUF_NEED_BMI2_FUNCTION
+static BMI2_TARGET_ATTRIBUTE
+size_t HUF_decompress4X1_usingDTable_internal_bmi2(void* dst, size_t dstSize, void const* cSrc,
+ size_t cSrcSize, HUF_DTable const* DTable) {
+ return HUF_decompress4X1_usingDTable_internal_body(dst, dstSize, cSrc, cSrcSize, DTable);
+}
+#endif
+
+#if HUF_NEED_DEFAULT_FUNCTION
+static
+size_t HUF_decompress4X1_usingDTable_internal_default(void* dst, size_t dstSize, void const* cSrc,
+ size_t cSrcSize, HUF_DTable const* DTable) {
+ return HUF_decompress4X1_usingDTable_internal_body(dst, dstSize, cSrc, cSrcSize, DTable);
+}
+#endif
+
+#if ZSTD_ENABLE_ASM_X86_64_BMI2
+
+HUF_ASM_DECL void HUF_decompress4X1_usingDTable_internal_bmi2_asm_loop(HUF_DecompressAsmArgs* args) ZSTDLIB_HIDDEN;
+
+static HUF_ASM_X86_64_BMI2_ATTRS
+size_t
+HUF_decompress4X1_usingDTable_internal_bmi2_asm(
+ void* dst, size_t dstSize,
+ const void* cSrc, size_t cSrcSize,
+ const HUF_DTable* DTable)
+{
+ void const* dt = DTable + 1;
+ const BYTE* const iend = (const BYTE*)cSrc + 6;
+ BYTE* const oend = (BYTE*)dst + dstSize;
+ HUF_DecompressAsmArgs args;
+ {
+ size_t const ret = HUF_DecompressAsmArgs_init(&args, dst, dstSize, cSrc, cSrcSize, DTable);
+ FORWARD_IF_ERROR(ret, "Failed to init asm args");
+ if (ret != 0)
+ return HUF_decompress4X1_usingDTable_internal_bmi2(dst, dstSize, cSrc, cSrcSize, DTable);
+ }
+
+ assert(args.ip[0] >= args.ilimit);
+ HUF_decompress4X1_usingDTable_internal_bmi2_asm_loop(&args);
+
+ /* Our loop guarantees that ip[] >= ilimit and that we haven't
+ * overwritten any op[].
+ */
+ assert(args.ip[0] >= iend);
+ assert(args.ip[1] >= iend);
+ assert(args.ip[2] >= iend);
+ assert(args.ip[3] >= iend);
+ assert(args.op[3] <= oend);
+ (void)iend;
+
+ /* finish bit streams one by one. */
+ {
+ size_t const segmentSize = (dstSize+3) / 4;
+ BYTE* segmentEnd = (BYTE*)dst;
+ int i;
+ for (i = 0; i < 4; ++i) {
+ BIT_DStream_t bit;
+ if (segmentSize <= (size_t)(oend - segmentEnd))
+ segmentEnd += segmentSize;
+ else
+ segmentEnd = oend;
+ FORWARD_IF_ERROR(HUF_initRemainingDStream(&bit, &args, i, segmentEnd), "corruption");
+ /* Decompress and validate that we've produced exactly the expected length. */
+ args.op[i] += HUF_decodeStreamX1(args.op[i], &bit, segmentEnd, (HUF_DEltX1 const*)dt, HUF_DECODER_FAST_TABLELOG);
+ if (args.op[i] != segmentEnd) return ERROR(corruption_detected);
+ }
+ }
+
+ /* decoded size */
+ return dstSize;
+}
+#endif /* ZSTD_ENABLE_ASM_X86_64_BMI2 */
typedef size_t (*HUF_decompress_usingDTable_t)(void *dst, size_t dstSize,
const void *cSrc,
@@ -447,8 +722,28 @@ typedef size_t (*HUF_decompress_usingDTable_t)(void *dst, size_t dstSize,
const HUF_DTable *DTable);
HUF_DGEN(HUF_decompress1X1_usingDTable_internal)
-HUF_DGEN(HUF_decompress4X1_usingDTable_internal)
+static size_t HUF_decompress4X1_usingDTable_internal(void* dst, size_t dstSize, void const* cSrc,
+ size_t cSrcSize, HUF_DTable const* DTable, int bmi2)
+{
+#if DYNAMIC_BMI2
+ if (bmi2) {
+# if ZSTD_ENABLE_ASM_X86_64_BMI2
+ return HUF_decompress4X1_usingDTable_internal_bmi2_asm(dst, dstSize, cSrc, cSrcSize, DTable);
+# else
+ return HUF_decompress4X1_usingDTable_internal_bmi2(dst, dstSize, cSrc, cSrcSize, DTable);
+# endif
+ }
+#else
+ (void)bmi2;
+#endif
+
+#if ZSTD_ENABLE_ASM_X86_64_BMI2 && defined(__BMI2__)
+ return HUF_decompress4X1_usingDTable_internal_bmi2_asm(dst, dstSize, cSrc, cSrcSize, DTable);
+#else
+ return HUF_decompress4X1_usingDTable_internal_default(dst, dstSize, cSrc, cSrcSize, DTable);
+#endif
+}
size_t HUF_decompress1X1_usingDTable(
@@ -518,106 +813,226 @@ size_t HUF_decompress4X1_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize,
/* *************************/
typedef struct { U16 sequence; BYTE nbBits; BYTE length; } HUF_DEltX2; /* double-symbols decoding */
-typedef struct { BYTE symbol; BYTE weight; } sortedSymbol_t;
+typedef struct { BYTE symbol; } sortedSymbol_t;
typedef U32 rankValCol_t[HUF_TABLELOG_MAX + 1];
typedef rankValCol_t rankVal_t[HUF_TABLELOG_MAX];
+/*
+ * Constructs a HUF_DEltX2 in a U32.
+ */
+static U32 HUF_buildDEltX2U32(U32 symbol, U32 nbBits, U32 baseSeq, int level)
+{
+ U32 seq;
+ DEBUG_STATIC_ASSERT(offsetof(HUF_DEltX2, sequence) == 0);
+ DEBUG_STATIC_ASSERT(offsetof(HUF_DEltX2, nbBits) == 2);
+ DEBUG_STATIC_ASSERT(offsetof(HUF_DEltX2, length) == 3);
+ DEBUG_STATIC_ASSERT(sizeof(HUF_DEltX2) == sizeof(U32));
+ if (MEM_isLittleEndian()) {
+ seq = level == 1 ? symbol : (baseSeq + (symbol << 8));
+ return seq + (nbBits << 16) + ((U32)level << 24);
+ } else {
+ seq = level == 1 ? (symbol << 8) : ((baseSeq << 8) + symbol);
+ return (seq << 16) + (nbBits << 8) + (U32)level;
+ }
+}
-/* HUF_fillDTableX2Level2() :
- * `rankValOrigin` must be a table of at least (HUF_TABLELOG_MAX + 1) U32 */
-static void HUF_fillDTableX2Level2(HUF_DEltX2* DTable, U32 sizeLog, const U32 consumed,
- const U32* rankValOrigin, const int minWeight,
- const sortedSymbol_t* sortedSymbols, const U32 sortedListSize,
- U32 nbBitsBaseline, U16 baseSeq, U32* wksp, size_t wkspSize)
+/*
+ * Constructs a HUF_DEltX2.
+ */
+static HUF_DEltX2 HUF_buildDEltX2(U32 symbol, U32 nbBits, U32 baseSeq, int level)
{
HUF_DEltX2 DElt;
- U32* rankVal = wksp;
+ U32 const val = HUF_buildDEltX2U32(symbol, nbBits, baseSeq, level);
+ DEBUG_STATIC_ASSERT(sizeof(DElt) == sizeof(val));
+ ZSTD_memcpy(&DElt, &val, sizeof(val));
+ return DElt;
+}
+
+/*
+ * Constructs 2 HUF_DEltX2s and packs them into a U64.
+ */
+static U64 HUF_buildDEltX2U64(U32 symbol, U32 nbBits, U16 baseSeq, int level)
+{
+ U32 DElt = HUF_buildDEltX2U32(symbol, nbBits, baseSeq, level);
+ return (U64)DElt + ((U64)DElt << 32);
+}
- assert(wkspSize >= HUF_TABLELOG_MAX + 1);
- (void)wkspSize;
- /* get pre-calculated rankVal */
- ZSTD_memcpy(rankVal, rankValOrigin, sizeof(U32) * (HUF_TABLELOG_MAX + 1));
+/*
+ * Fills the DTable rank with all the symbols from [begin, end) that are each
+ * nbBits long.
+ *
+ * @param DTableRank The start of the rank in the DTable.
+ * @param begin The first symbol to fill (inclusive).
+ * @param end The last symbol to fill (exclusive).
+ * @param nbBits Each symbol is nbBits long.
+ * @param tableLog The table log.
+ * @param baseSeq If level == 1 { 0 } else { the first level symbol }
+ * @param level The level in the table. Must be 1 or 2.
+ */
+static void HUF_fillDTableX2ForWeight(
+ HUF_DEltX2* DTableRank,
+ sortedSymbol_t const* begin, sortedSymbol_t const* end,
+ U32 nbBits, U32 tableLog,
+ U16 baseSeq, int const level)
+{
+ U32 const length = 1U << ((tableLog - nbBits) & 0x1F /* quiet static-analyzer */);
+ const sortedSymbol_t* ptr;
+ assert(level >= 1 && level <= 2);
+ switch (length) {
+ case 1:
+ for (ptr = begin; ptr != end; ++ptr) {
+ HUF_DEltX2 const DElt = HUF_buildDEltX2(ptr->symbol, nbBits, baseSeq, level);
+ *DTableRank++ = DElt;
+ }
+ break;
+ case 2:
+ for (ptr = begin; ptr != end; ++ptr) {
+ HUF_DEltX2 const DElt = HUF_buildDEltX2(ptr->symbol, nbBits, baseSeq, level);
+ DTableRank[0] = DElt;
+ DTableRank[1] = DElt;
+ DTableRank += 2;
+ }
+ break;
+ case 4:
+ for (ptr = begin; ptr != end; ++ptr) {
+ U64 const DEltX2 = HUF_buildDEltX2U64(ptr->symbol, nbBits, baseSeq, level);
+ ZSTD_memcpy(DTableRank + 0, &DEltX2, sizeof(DEltX2));
+ ZSTD_memcpy(DTableRank + 2, &DEltX2, sizeof(DEltX2));
+ DTableRank += 4;
+ }
+ break;
+ case 8:
+ for (ptr = begin; ptr != end; ++ptr) {
+ U64 const DEltX2 = HUF_buildDEltX2U64(ptr->symbol, nbBits, baseSeq, level);
+ ZSTD_memcpy(DTableRank + 0, &DEltX2, sizeof(DEltX2));
+ ZSTD_memcpy(DTableRank + 2, &DEltX2, sizeof(DEltX2));
+ ZSTD_memcpy(DTableRank + 4, &DEltX2, sizeof(DEltX2));
+ ZSTD_memcpy(DTableRank + 6, &DEltX2, sizeof(DEltX2));
+ DTableRank += 8;
+ }
+ break;
+ default:
+ for (ptr = begin; ptr != end; ++ptr) {
+ U64 const DEltX2 = HUF_buildDEltX2U64(ptr->symbol, nbBits, baseSeq, level);
+ HUF_DEltX2* const DTableRankEnd = DTableRank + length;
+ for (; DTableRank != DTableRankEnd; DTableRank += 8) {
+ ZSTD_memcpy(DTableRank + 0, &DEltX2, sizeof(DEltX2));
+ ZSTD_memcpy(DTableRank + 2, &DEltX2, sizeof(DEltX2));
+ ZSTD_memcpy(DTableRank + 4, &DEltX2, sizeof(DEltX2));
+ ZSTD_memcpy(DTableRank + 6, &DEltX2, sizeof(DEltX2));
+ }
+ }
+ break;
+ }
+}
- /* fill skipped values */
+/* HUF_fillDTableX2Level2() :
+ * `rankValOrigin` must be a table of at least (HUF_TABLELOG_MAX + 1) U32 */
+static void HUF_fillDTableX2Level2(HUF_DEltX2* DTable, U32 targetLog, const U32 consumedBits,
+ const U32* rankVal, const int minWeight, const int maxWeight1,
+ const sortedSymbol_t* sortedSymbols, U32 const* rankStart,
+ U32 nbBitsBaseline, U16 baseSeq)
+{
+ /* Fill skipped values (all positions up to rankVal[minWeight]).
+ * These are positions only get a single symbol because the combined weight
+ * is too large.
+ */
if (minWeight>1) {
- U32 i, skipSize = rankVal[minWeight];
- MEM_writeLE16(&(DElt.sequence), baseSeq);
- DElt.nbBits = (BYTE)(consumed);
- DElt.length = 1;
- for (i = 0; i < skipSize; i++)
- DTable[i] = DElt;
+ U32 const length = 1U << ((targetLog - consumedBits) & 0x1F /* quiet static-analyzer */);
+ U64 const DEltX2 = HUF_buildDEltX2U64(baseSeq, consumedBits, /* baseSeq */ 0, /* level */ 1);
+ int const skipSize = rankVal[minWeight];
+ assert(length > 1);
+ assert((U32)skipSize < length);
+ switch (length) {
+ case 2:
+ assert(skipSize == 1);
+ ZSTD_memcpy(DTable, &DEltX2, sizeof(DEltX2));
+ break;
+ case 4:
+ assert(skipSize <= 4);
+ ZSTD_memcpy(DTable + 0, &DEltX2, sizeof(DEltX2));
+ ZSTD_memcpy(DTable + 2, &DEltX2, sizeof(DEltX2));
+ break;
+ default:
+ {
+ int i;
+ for (i = 0; i < skipSize; i += 8) {
+ ZSTD_memcpy(DTable + i + 0, &DEltX2, sizeof(DEltX2));
+ ZSTD_memcpy(DTable + i + 2, &DEltX2, sizeof(DEltX2));
+ ZSTD_memcpy(DTable + i + 4, &DEltX2, sizeof(DEltX2));
+ ZSTD_memcpy(DTable + i + 6, &DEltX2, sizeof(DEltX2));
+ }
+ }
+ }
}
- /* fill DTable */
- { U32 s; for (s=0; s<sortedListSize; s++) { /* note : sortedSymbols already skipped */
- const U32 symbol = sortedSymbols[s].symbol;
- const U32 weight = sortedSymbols[s].weight;
- const U32 nbBits = nbBitsBaseline - weight;
- const U32 length = 1 << (sizeLog-nbBits);
- const U32 start = rankVal[weight];
- U32 i = start;
- const U32 end = start + length;
-
- MEM_writeLE16(&(DElt.sequence), (U16)(baseSeq + (symbol << 8)));
- DElt.nbBits = (BYTE)(nbBits + consumed);
- DElt.length = 2;
- do { DTable[i++] = DElt; } while (i<end); /* since length >= 1 */
-
- rankVal[weight] += length;
- } }
+ /* Fill each of the second level symbols by weight. */
+ {
+ int w;
+ for (w = minWeight; w < maxWeight1; ++w) {
+ int const begin = rankStart[w];
+ int const end = rankStart[w+1];
+ U32 const nbBits = nbBitsBaseline - w;
+ U32 const totalBits = nbBits + consumedBits;
+ HUF_fillDTableX2ForWeight(
+ DTable + rankVal[w],
+ sortedSymbols + begin, sortedSymbols + end,
+ totalBits, targetLog,
+ baseSeq, /* level */ 2);
+ }
+ }
}
-
static void HUF_fillDTableX2(HUF_DEltX2* DTable, const U32 targetLog,
- const sortedSymbol_t* sortedList, const U32 sortedListSize,
+ const sortedSymbol_t* sortedList,
const U32* rankStart, rankVal_t rankValOrigin, const U32 maxWeight,
- const U32 nbBitsBaseline, U32* wksp, size_t wkspSize)
+ const U32 nbBitsBaseline)
{
- U32* rankVal = wksp;
+ U32* const rankVal = rankValOrigin[0];
const int scaleLog = nbBitsBaseline - targetLog; /* note : targetLog >= srcLog, hence scaleLog <= 1 */
const U32 minBits = nbBitsBaseline - maxWeight;
- U32 s;
-
- assert(wkspSize >= HUF_TABLELOG_MAX + 1);
- wksp += HUF_TABLELOG_MAX + 1;
- wkspSize -= HUF_TABLELOG_MAX + 1;
-
- ZSTD_memcpy(rankVal, rankValOrigin, sizeof(U32) * (HUF_TABLELOG_MAX + 1));
-
- /* fill DTable */
- for (s=0; s<sortedListSize; s++) {
- const U16 symbol = sortedList[s].symbol;
- const U32 weight = sortedList[s].weight;
- const U32 nbBits = nbBitsBaseline - weight;
- const U32 start = rankVal[weight];
- const U32 length = 1 << (targetLog-nbBits);
-
- if (targetLog-nbBits >= minBits) { /* enough room for a second symbol */
- U32 sortedRank;
+ int w;
+ int const wEnd = (int)maxWeight + 1;
+
+ /* Fill DTable in order of weight. */
+ for (w = 1; w < wEnd; ++w) {
+ int const begin = (int)rankStart[w];
+ int const end = (int)rankStart[w+1];
+ U32 const nbBits = nbBitsBaseline - w;
+
+ if (targetLog-nbBits >= minBits) {
+ /* Enough room for a second symbol. */
+ int start = rankVal[w];
+ U32 const length = 1U << ((targetLog - nbBits) & 0x1F /* quiet static-analyzer */);
int minWeight = nbBits + scaleLog;
+ int s;
if (minWeight < 1) minWeight = 1;
- sortedRank = rankStart[minWeight];
- HUF_fillDTableX2Level2(DTable+start, targetLog-nbBits, nbBits,
- rankValOrigin[nbBits], minWeight,
- sortedList+sortedRank, sortedListSize-sortedRank,
- nbBitsBaseline, symbol, wksp, wkspSize);
+ /* Fill the DTable for every symbol of weight w.
+ * These symbols get at least 1 second symbol.
+ */
+ for (s = begin; s != end; ++s) {
+ HUF_fillDTableX2Level2(
+ DTable + start, targetLog, nbBits,
+ rankValOrigin[nbBits], minWeight, wEnd,
+ sortedList, rankStart,
+ nbBitsBaseline, sortedList[s].symbol);
+ start += length;
+ }
} else {
- HUF_DEltX2 DElt;
- MEM_writeLE16(&(DElt.sequence), symbol);
- DElt.nbBits = (BYTE)(nbBits);
- DElt.length = 1;
- { U32 const end = start + length;
- U32 u;
- for (u = start; u < end; u++) DTable[u] = DElt;
- } }
- rankVal[weight] += length;
+ /* Only a single symbol. */
+ HUF_fillDTableX2ForWeight(
+ DTable + rankVal[w],
+ sortedList + begin, sortedList + end,
+ nbBits, targetLog,
+ /* baseSeq */ 0, /* level */ 1);
+ }
}
}
typedef struct {
rankValCol_t rankVal[HUF_TABLELOG_MAX];
U32 rankStats[HUF_TABLELOG_MAX + 1];
- U32 rankStart0[HUF_TABLELOG_MAX + 2];
+ U32 rankStart0[HUF_TABLELOG_MAX + 3];
sortedSymbol_t sortedSymbol[HUF_SYMBOLVALUE_MAX + 1];
BYTE weightList[HUF_SYMBOLVALUE_MAX + 1];
U32 calleeWksp[HUF_READ_STATS_WORKSPACE_SIZE_U32];
@@ -627,9 +1042,16 @@ size_t HUF_readDTableX2_wksp(HUF_DTable* DTable,
const void* src, size_t srcSize,
void* workSpace, size_t wkspSize)
{
- U32 tableLog, maxW, sizeOfSort, nbSymbols;
+ return HUF_readDTableX2_wksp_bmi2(DTable, src, srcSize, workSpace, wkspSize, /* bmi2 */ 0);
+}
+
+size_t HUF_readDTableX2_wksp_bmi2(HUF_DTable* DTable,
+ const void* src, size_t srcSize,
+ void* workSpace, size_t wkspSize, int bmi2)
+{
+ U32 tableLog, maxW, nbSymbols;
DTableDesc dtd = HUF_getDTableDesc(DTable);
- U32 const maxTableLog = dtd.maxTableLog;
+ U32 maxTableLog = dtd.maxTableLog;
size_t iSize;
void* dtPtr = DTable+1; /* force compiler to avoid strict-aliasing */
HUF_DEltX2* const dt = (HUF_DEltX2*)dtPtr;
@@ -647,11 +1069,12 @@ size_t HUF_readDTableX2_wksp(HUF_DTable* DTable,
if (maxTableLog > HUF_TABLELOG_MAX) return ERROR(tableLog_tooLarge);
/* ZSTD_memset(weightList, 0, sizeof(weightList)); */ /* is not necessary, even though some analyzer complain ... */
- iSize = HUF_readStats_wksp(wksp->weightList, HUF_SYMBOLVALUE_MAX + 1, wksp->rankStats, &nbSymbols, &tableLog, src, srcSize, wksp->calleeWksp, sizeof(wksp->calleeWksp), /* bmi2 */ 0);
+ iSize = HUF_readStats_wksp(wksp->weightList, HUF_SYMBOLVALUE_MAX + 1, wksp->rankStats, &nbSymbols, &tableLog, src, srcSize, wksp->calleeWksp, sizeof(wksp->calleeWksp), bmi2);
if (HUF_isError(iSize)) return iSize;
/* check result */
if (tableLog > maxTableLog) return ERROR(tableLog_tooLarge); /* DTable can't fit code depth */
+ if (tableLog <= HUF_DECODER_FAST_TABLELOG && maxTableLog > HUF_DECODER_FAST_TABLELOG) maxTableLog = HUF_DECODER_FAST_TABLELOG;
/* find maxWeight */
for (maxW = tableLog; wksp->rankStats[maxW]==0; maxW--) {} /* necessarily finds a solution before 0 */
@@ -664,7 +1087,7 @@ size_t HUF_readDTableX2_wksp(HUF_DTable* DTable,
rankStart[w] = curr;
}
rankStart[0] = nextRankStart; /* put all 0w symbols at the end of sorted list*/
- sizeOfSort = nextRankStart;
+ rankStart[maxW+1] = nextRankStart;
}
/* sort symbols by weight */
@@ -673,7 +1096,6 @@ size_t HUF_readDTableX2_wksp(HUF_DTable* DTable,
U32 const w = wksp->weightList[s];
U32 const r = rankStart[w]++;
wksp->sortedSymbol[r].symbol = (BYTE)s;
- wksp->sortedSymbol[r].weight = (BYTE)w;
}
rankStart[0] = 0; /* forget 0w symbols; this is beginning of weight(1) */
}
@@ -698,10 +1120,9 @@ size_t HUF_readDTableX2_wksp(HUF_DTable* DTable,
} } } }
HUF_fillDTableX2(dt, maxTableLog,
- wksp->sortedSymbol, sizeOfSort,
+ wksp->sortedSymbol,
wksp->rankStart0, wksp->rankVal, maxW,
- tableLog+1,
- wksp->calleeWksp, sizeof(wksp->calleeWksp) / sizeof(U32));
+ tableLog+1);
dtd.tableLog = (BYTE)maxTableLog;
dtd.tableType = 1;
@@ -714,7 +1135,7 @@ FORCE_INLINE_TEMPLATE U32
HUF_decodeSymbolX2(void* op, BIT_DStream_t* DStream, const HUF_DEltX2* dt, const U32 dtLog)
{
size_t const val = BIT_lookBitsFast(DStream, dtLog); /* note : dtLog >= 1 */
- ZSTD_memcpy(op, dt+val, 2);
+ ZSTD_memcpy(op, &dt[val].sequence, 2);
BIT_skipBits(DStream, dt[val].nbBits);
return dt[val].length;
}
@@ -723,15 +1144,17 @@ FORCE_INLINE_TEMPLATE U32
HUF_decodeLastSymbolX2(void* op, BIT_DStream_t* DStream, const HUF_DEltX2* dt, const U32 dtLog)
{
size_t const val = BIT_lookBitsFast(DStream, dtLog); /* note : dtLog >= 1 */
- ZSTD_memcpy(op, dt+val, 1);
- if (dt[val].length==1) BIT_skipBits(DStream, dt[val].nbBits);
- else {
+ ZSTD_memcpy(op, &dt[val].sequence, 1);
+ if (dt[val].length==1) {
+ BIT_skipBits(DStream, dt[val].nbBits);
+ } else {
if (DStream->bitsConsumed < (sizeof(DStream->bitContainer)*8)) {
BIT_skipBits(DStream, dt[val].nbBits);
if (DStream->bitsConsumed > (sizeof(DStream->bitContainer)*8))
/* ugly hack; works only because it's the last symbol. Note : can't easily extract nbBits from just this symbol */
DStream->bitsConsumed = (sizeof(DStream->bitContainer)*8);
- } }
+ }
+ }
return 1;
}
@@ -753,19 +1176,37 @@ HUF_decodeStreamX2(BYTE* p, BIT_DStream_t* bitDPtr, BYTE* const pEnd,
BYTE* const pStart = p;
/* up to 8 symbols at a time */
- while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p < pEnd-(sizeof(bitDPtr->bitContainer)-1))) {
- HUF_DECODE_SYMBOLX2_2(p, bitDPtr);
- HUF_DECODE_SYMBOLX2_1(p, bitDPtr);
- HUF_DECODE_SYMBOLX2_2(p, bitDPtr);
- HUF_DECODE_SYMBOLX2_0(p, bitDPtr);
+ if ((size_t)(pEnd - p) >= sizeof(bitDPtr->bitContainer)) {
+ if (dtLog <= 11 && MEM_64bits()) {
+ /* up to 10 symbols at a time */
+ while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p < pEnd-9)) {
+ HUF_DECODE_SYMBOLX2_0(p, bitDPtr);
+ HUF_DECODE_SYMBOLX2_0(p, bitDPtr);
+ HUF_DECODE_SYMBOLX2_0(p, bitDPtr);
+ HUF_DECODE_SYMBOLX2_0(p, bitDPtr);
+ HUF_DECODE_SYMBOLX2_0(p, bitDPtr);
+ }
+ } else {
+ /* up to 8 symbols at a time */
+ while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p < pEnd-(sizeof(bitDPtr->bitContainer)-1))) {
+ HUF_DECODE_SYMBOLX2_2(p, bitDPtr);
+ HUF_DECODE_SYMBOLX2_1(p, bitDPtr);
+ HUF_DECODE_SYMBOLX2_2(p, bitDPtr);
+ HUF_DECODE_SYMBOLX2_0(p, bitDPtr);
+ }
+ }
+ } else {
+ BIT_reloadDStream(bitDPtr);
}
/* closer to end : up to 2 symbols at a time */
- while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p <= pEnd-2))
- HUF_DECODE_SYMBOLX2_0(p, bitDPtr);
+ if ((size_t)(pEnd - p) >= 2) {
+ while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p <= pEnd-2))
+ HUF_DECODE_SYMBOLX2_0(p, bitDPtr);
- while (p <= pEnd-2)
- HUF_DECODE_SYMBOLX2_0(p, bitDPtr); /* no need to reload : reached the end of DStream */
+ while (p <= pEnd-2)
+ HUF_DECODE_SYMBOLX2_0(p, bitDPtr); /* no need to reload : reached the end of DStream */
+ }
if (p < pEnd)
p += HUF_decodeLastSymbolX2(p, bitDPtr, dt, dtLog);
@@ -799,7 +1240,6 @@ HUF_decompress1X2_usingDTable_internal_body(
/* decoded size */
return dstSize;
}
-
FORCE_INLINE_TEMPLATE size_t
HUF_decompress4X2_usingDTable_internal_body(
void* dst, size_t dstSize,
@@ -841,57 +1281,60 @@ HUF_decompress4X2_usingDTable_internal_body(
U32 const dtLog = dtd.tableLog;
if (length4 > cSrcSize) return ERROR(corruption_detected); /* overflow */
+ if (opStart4 > oend) return ERROR(corruption_detected); /* overflow */
CHECK_F( BIT_initDStream(&bitD1, istart1, length1) );
CHECK_F( BIT_initDStream(&bitD2, istart2, length2) );
CHECK_F( BIT_initDStream(&bitD3, istart3, length3) );
CHECK_F( BIT_initDStream(&bitD4, istart4, length4) );
/* 16-32 symbols per loop (4-8 symbols per stream) */
- for ( ; (endSignal) & (op4 < olimit); ) {
+ if ((size_t)(oend - op4) >= sizeof(size_t)) {
+ for ( ; (endSignal) & (op4 < olimit); ) {
#if defined(__clang__) && (defined(__x86_64__) || defined(__i386__))
- HUF_DECODE_SYMBOLX2_2(op1, &bitD1);
- HUF_DECODE_SYMBOLX2_1(op1, &bitD1);
- HUF_DECODE_SYMBOLX2_2(op1, &bitD1);
- HUF_DECODE_SYMBOLX2_0(op1, &bitD1);
- HUF_DECODE_SYMBOLX2_2(op2, &bitD2);
- HUF_DECODE_SYMBOLX2_1(op2, &bitD2);
- HUF_DECODE_SYMBOLX2_2(op2, &bitD2);
- HUF_DECODE_SYMBOLX2_0(op2, &bitD2);
- endSignal &= BIT_reloadDStreamFast(&bitD1) == BIT_DStream_unfinished;
- endSignal &= BIT_reloadDStreamFast(&bitD2) == BIT_DStream_unfinished;
- HUF_DECODE_SYMBOLX2_2(op3, &bitD3);
- HUF_DECODE_SYMBOLX2_1(op3, &bitD3);
- HUF_DECODE_SYMBOLX2_2(op3, &bitD3);
- HUF_DECODE_SYMBOLX2_0(op3, &bitD3);
- HUF_DECODE_SYMBOLX2_2(op4, &bitD4);
- HUF_DECODE_SYMBOLX2_1(op4, &bitD4);
- HUF_DECODE_SYMBOLX2_2(op4, &bitD4);
- HUF_DECODE_SYMBOLX2_0(op4, &bitD4);
- endSignal &= BIT_reloadDStreamFast(&bitD3) == BIT_DStream_unfinished;
- endSignal &= BIT_reloadDStreamFast(&bitD4) == BIT_DStream_unfinished;
+ HUF_DECODE_SYMBOLX2_2(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_1(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_2(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_0(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_2(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_1(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_2(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_0(op2, &bitD2);
+ endSignal &= BIT_reloadDStreamFast(&bitD1) == BIT_DStream_unfinished;
+ endSignal &= BIT_reloadDStreamFast(&bitD2) == BIT_DStream_unfinished;
+ HUF_DECODE_SYMBOLX2_2(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_1(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_2(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_0(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_2(op4, &bitD4);
+ HUF_DECODE_SYMBOLX2_1(op4, &bitD4);
+ HUF_DECODE_SYMBOLX2_2(op4, &bitD4);
+ HUF_DECODE_SYMBOLX2_0(op4, &bitD4);
+ endSignal &= BIT_reloadDStreamFast(&bitD3) == BIT_DStream_unfinished;
+ endSignal &= BIT_reloadDStreamFast(&bitD4) == BIT_DStream_unfinished;
#else
- HUF_DECODE_SYMBOLX2_2(op1, &bitD1);
- HUF_DECODE_SYMBOLX2_2(op2, &bitD2);
- HUF_DECODE_SYMBOLX2_2(op3, &bitD3);
- HUF_DECODE_SYMBOLX2_2(op4, &bitD4);
- HUF_DECODE_SYMBOLX2_1(op1, &bitD1);
- HUF_DECODE_SYMBOLX2_1(op2, &bitD2);
- HUF_DECODE_SYMBOLX2_1(op3, &bitD3);
- HUF_DECODE_SYMBOLX2_1(op4, &bitD4);
- HUF_DECODE_SYMBOLX2_2(op1, &bitD1);
- HUF_DECODE_SYMBOLX2_2(op2, &bitD2);
- HUF_DECODE_SYMBOLX2_2(op3, &bitD3);
- HUF_DECODE_SYMBOLX2_2(op4, &bitD4);
- HUF_DECODE_SYMBOLX2_0(op1, &bitD1);
- HUF_DECODE_SYMBOLX2_0(op2, &bitD2);
- HUF_DECODE_SYMBOLX2_0(op3, &bitD3);
- HUF_DECODE_SYMBOLX2_0(op4, &bitD4);
- endSignal = (U32)LIKELY((U32)
- (BIT_reloadDStreamFast(&bitD1) == BIT_DStream_unfinished)
- & (BIT_reloadDStreamFast(&bitD2) == BIT_DStream_unfinished)
- & (BIT_reloadDStreamFast(&bitD3) == BIT_DStream_unfinished)
- & (BIT_reloadDStreamFast(&bitD4) == BIT_DStream_unfinished));
+ HUF_DECODE_SYMBOLX2_2(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_2(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_2(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_2(op4, &bitD4);
+ HUF_DECODE_SYMBOLX2_1(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_1(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_1(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_1(op4, &bitD4);
+ HUF_DECODE_SYMBOLX2_2(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_2(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_2(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_2(op4, &bitD4);
+ HUF_DECODE_SYMBOLX2_0(op1, &bitD1);
+ HUF_DECODE_SYMBOLX2_0(op2, &bitD2);
+ HUF_DECODE_SYMBOLX2_0(op3, &bitD3);
+ HUF_DECODE_SYMBOLX2_0(op4, &bitD4);
+ endSignal = (U32)LIKELY((U32)
+ (BIT_reloadDStreamFast(&bitD1) == BIT_DStream_unfinished)
+ & (BIT_reloadDStreamFast(&bitD2) == BIT_DStream_unfinished)
+ & (BIT_reloadDStreamFast(&bitD3) == BIT_DStream_unfinished)
+ & (BIT_reloadDStreamFast(&bitD4) == BIT_DStream_unfinished));
#endif
+ }
}
/* check corruption */
@@ -915,8 +1358,99 @@ HUF_decompress4X2_usingDTable_internal_body(
}
}
+#if HUF_NEED_BMI2_FUNCTION
+static BMI2_TARGET_ATTRIBUTE
+size_t HUF_decompress4X2_usingDTable_internal_bmi2(void* dst, size_t dstSize, void const* cSrc,
+ size_t cSrcSize, HUF_DTable const* DTable) {
+ return HUF_decompress4X2_usingDTable_internal_body(dst, dstSize, cSrc, cSrcSize, DTable);
+}
+#endif
+
+#if HUF_NEED_DEFAULT_FUNCTION
+static
+size_t HUF_decompress4X2_usingDTable_internal_default(void* dst, size_t dstSize, void const* cSrc,
+ size_t cSrcSize, HUF_DTable const* DTable) {
+ return HUF_decompress4X2_usingDTable_internal_body(dst, dstSize, cSrc, cSrcSize, DTable);
+}
+#endif
+
+#if ZSTD_ENABLE_ASM_X86_64_BMI2
+
+HUF_ASM_DECL void HUF_decompress4X2_usingDTable_internal_bmi2_asm_loop(HUF_DecompressAsmArgs* args) ZSTDLIB_HIDDEN;
+
+static HUF_ASM_X86_64_BMI2_ATTRS size_t
+HUF_decompress4X2_usingDTable_internal_bmi2_asm(
+ void* dst, size_t dstSize,
+ const void* cSrc, size_t cSrcSize,
+ const HUF_DTable* DTable) {
+ void const* dt = DTable + 1;
+ const BYTE* const iend = (const BYTE*)cSrc + 6;
+ BYTE* const oend = (BYTE*)dst + dstSize;
+ HUF_DecompressAsmArgs args;
+ {
+ size_t const ret = HUF_DecompressAsmArgs_init(&args, dst, dstSize, cSrc, cSrcSize, DTable);
+ FORWARD_IF_ERROR(ret, "Failed to init asm args");
+ if (ret != 0)
+ return HUF_decompress4X2_usingDTable_internal_bmi2(dst, dstSize, cSrc, cSrcSize, DTable);
+ }
+
+ assert(args.ip[0] >= args.ilimit);
+ HUF_decompress4X2_usingDTable_internal_bmi2_asm_loop(&args);
+
+ /* note : op4 already verified within main loop */
+ assert(args.ip[0] >= iend);
+ assert(args.ip[1] >= iend);
+ assert(args.ip[2] >= iend);
+ assert(args.ip[3] >= iend);
+ assert(args.op[3] <= oend);
+ (void)iend;
+
+ /* finish bitStreams one by one */
+ {
+ size_t const segmentSize = (dstSize+3) / 4;
+ BYTE* segmentEnd = (BYTE*)dst;
+ int i;
+ for (i = 0; i < 4; ++i) {
+ BIT_DStream_t bit;
+ if (segmentSize <= (size_t)(oend - segmentEnd))
+ segmentEnd += segmentSize;
+ else
+ segmentEnd = oend;
+ FORWARD_IF_ERROR(HUF_initRemainingDStream(&bit, &args, i, segmentEnd), "corruption");
+ args.op[i] += HUF_decodeStreamX2(args.op[i], &bit, segmentEnd, (HUF_DEltX2 const*)dt, HUF_DECODER_FAST_TABLELOG);
+ if (args.op[i] != segmentEnd)
+ return ERROR(corruption_detected);
+ }
+ }
+
+ /* decoded size */
+ return dstSize;
+}
+#endif /* ZSTD_ENABLE_ASM_X86_64_BMI2 */
+
+static size_t HUF_decompress4X2_usingDTable_internal(void* dst, size_t dstSize, void const* cSrc,
+ size_t cSrcSize, HUF_DTable const* DTable, int bmi2)
+{
+#if DYNAMIC_BMI2
+ if (bmi2) {
+# if ZSTD_ENABLE_ASM_X86_64_BMI2
+ return HUF_decompress4X2_usingDTable_internal_bmi2_asm(dst, dstSize, cSrc, cSrcSize, DTable);
+# else
+ return HUF_decompress4X2_usingDTable_internal_bmi2(dst, dstSize, cSrc, cSrcSize, DTable);
+# endif
+ }
+#else
+ (void)bmi2;
+#endif
+
+#if ZSTD_ENABLE_ASM_X86_64_BMI2 && defined(__BMI2__)
+ return HUF_decompress4X2_usingDTable_internal_bmi2_asm(dst, dstSize, cSrc, cSrcSize, DTable);
+#else
+ return HUF_decompress4X2_usingDTable_internal_default(dst, dstSize, cSrc, cSrcSize, DTable);
+#endif
+}
+
HUF_DGEN(HUF_decompress1X2_usingDTable_internal)
-HUF_DGEN(HUF_decompress4X2_usingDTable_internal)
size_t HUF_decompress1X2_usingDTable(
void* dst, size_t dstSize,
@@ -1025,25 +1559,25 @@ size_t HUF_decompress4X_usingDTable(void* dst, size_t maxDstSize,
#if !defined(HUF_FORCE_DECOMPRESS_X1) && !defined(HUF_FORCE_DECOMPRESS_X2)
typedef struct { U32 tableTime; U32 decode256Time; } algo_time_t;
-static const algo_time_t algoTime[16 /* Quantization */][3 /* single, double, quad */] =
+static const algo_time_t algoTime[16 /* Quantization */][2 /* single, double */] =
{
/* single, double, quad */
- {{0,0}, {1,1}, {2,2}}, /* Q==0 : impossible */
- {{0,0}, {1,1}, {2,2}}, /* Q==1 : impossible */
- {{ 38,130}, {1313, 74}, {2151, 38}}, /* Q == 2 : 12-18% */
- {{ 448,128}, {1353, 74}, {2238, 41}}, /* Q == 3 : 18-25% */
- {{ 556,128}, {1353, 74}, {2238, 47}}, /* Q == 4 : 25-32% */
- {{ 714,128}, {1418, 74}, {2436, 53}}, /* Q == 5 : 32-38% */
- {{ 883,128}, {1437, 74}, {2464, 61}}, /* Q == 6 : 38-44% */
- {{ 897,128}, {1515, 75}, {2622, 68}}, /* Q == 7 : 44-50% */
- {{ 926,128}, {1613, 75}, {2730, 75}}, /* Q == 8 : 50-56% */
- {{ 947,128}, {1729, 77}, {3359, 77}}, /* Q == 9 : 56-62% */
- {{1107,128}, {2083, 81}, {4006, 84}}, /* Q ==10 : 62-69% */
- {{1177,128}, {2379, 87}, {4785, 88}}, /* Q ==11 : 69-75% */
- {{1242,128}, {2415, 93}, {5155, 84}}, /* Q ==12 : 75-81% */
- {{1349,128}, {2644,106}, {5260,106}}, /* Q ==13 : 81-87% */
- {{1455,128}, {2422,124}, {4174,124}}, /* Q ==14 : 87-93% */
- {{ 722,128}, {1891,145}, {1936,146}}, /* Q ==15 : 93-99% */
+ {{0,0}, {1,1}}, /* Q==0 : impossible */
+ {{0,0}, {1,1}}, /* Q==1 : impossible */
+ {{ 150,216}, { 381,119}}, /* Q == 2 : 12-18% */
+ {{ 170,205}, { 514,112}}, /* Q == 3 : 18-25% */
+ {{ 177,199}, { 539,110}}, /* Q == 4 : 25-32% */
+ {{ 197,194}, { 644,107}}, /* Q == 5 : 32-38% */
+ {{ 221,192}, { 735,107}}, /* Q == 6 : 38-44% */
+ {{ 256,189}, { 881,106}}, /* Q == 7 : 44-50% */
+ {{ 359,188}, {1167,109}}, /* Q == 8 : 50-56% */
+ {{ 582,187}, {1570,114}}, /* Q == 9 : 56-62% */
+ {{ 688,187}, {1712,122}}, /* Q ==10 : 62-69% */
+ {{ 825,186}, {1965,136}}, /* Q ==11 : 69-75% */
+ {{ 976,185}, {2131,150}}, /* Q ==12 : 75-81% */
+ {{1180,186}, {2070,175}}, /* Q ==13 : 81-87% */
+ {{1377,185}, {1731,202}}, /* Q ==14 : 87-93% */
+ {{1412,185}, {1695,202}}, /* Q ==15 : 93-99% */
};
#endif
@@ -1070,7 +1604,7 @@ U32 HUF_selectDecoder (size_t dstSize, size_t cSrcSize)
U32 const D256 = (U32)(dstSize >> 8);
U32 const DTime0 = algoTime[Q][0].tableTime + (algoTime[Q][0].decode256Time * D256);
U32 DTime1 = algoTime[Q][1].tableTime + (algoTime[Q][1].decode256Time * D256);
- DTime1 += DTime1 >> 3; /* advantage to algorithm using less memory, to reduce cache eviction */
+ DTime1 += DTime1 >> 5; /* small advantage to algorithm using less memory, to reduce cache eviction */
return DTime1 < DTime0;
}
#endif
diff --git a/lib/zstd/decompress/zstd_decompress.c b/lib/zstd/decompress/zstd_decompress.c
index b4d81d84479a..b9b935a9f5c0 100644
--- a/lib/zstd/decompress/zstd_decompress.c
+++ b/lib/zstd/decompress/zstd_decompress.c
@@ -53,7 +53,6 @@
* Dependencies
*********************************************************/
#include "../common/zstd_deps.h" /* ZSTD_memcpy, ZSTD_memmove, ZSTD_memset */
-#include "../common/cpu.h" /* bmi2 */
#include "../common/mem.h" /* low level memory routines */
#define FSE_STATIC_LINKING_ONLY
#include "../common/fse.h"
@@ -252,11 +251,11 @@ static void ZSTD_initDCtx_internal(ZSTD_DCtx* dctx)
dctx->inBuffSize = 0;
dctx->outBuffSize = 0;
dctx->streamStage = zdss_init;
- dctx->legacyContext = NULL;
- dctx->previousLegacyVersion = 0;
dctx->noForwardProgress = 0;
dctx->oversizedDuration = 0;
- dctx->bmi2 = ZSTD_cpuid_bmi2(ZSTD_cpuid());
+#if DYNAMIC_BMI2
+ dctx->bmi2 = ZSTD_cpuSupportsBmi2();
+#endif
dctx->ddictSet = NULL;
ZSTD_DCtx_resetParameters(dctx);
#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
@@ -277,8 +276,7 @@ ZSTD_DCtx* ZSTD_initStaticDCtx(void *workspace, size_t workspaceSize)
return dctx;
}
-ZSTD_DCtx* ZSTD_createDCtx_advanced(ZSTD_customMem customMem)
-{
+static ZSTD_DCtx* ZSTD_createDCtx_internal(ZSTD_customMem customMem) {
if ((!customMem.customAlloc) ^ (!customMem.customFree)) return NULL;
{ ZSTD_DCtx* const dctx = (ZSTD_DCtx*)ZSTD_customMalloc(sizeof(*dctx), customMem);
@@ -289,10 +287,15 @@ ZSTD_DCtx* ZSTD_createDCtx_advanced(ZSTD_customMem customMem)
}
}
+ZSTD_DCtx* ZSTD_createDCtx_advanced(ZSTD_customMem customMem)
+{
+ return ZSTD_createDCtx_internal(customMem);
+}
+
ZSTD_DCtx* ZSTD_createDCtx(void)
{
DEBUGLOG(3, "ZSTD_createDCtx");
- return ZSTD_createDCtx_advanced(ZSTD_defaultCMem);
+ return ZSTD_createDCtx_internal(ZSTD_defaultCMem);
}
static void ZSTD_clearDict(ZSTD_DCtx* dctx)
@@ -370,6 +373,19 @@ unsigned ZSTD_isFrame(const void* buffer, size_t size)
return 0;
}
+/*! ZSTD_isSkippableFrame() :
+ * Tells if the content of `buffer` starts with a valid Frame Identifier for a skippable frame.
+ * Note : Frame Identifier is 4 bytes. If `size < 4`, @return will always be 0.
+ */
+unsigned ZSTD_isSkippableFrame(const void* buffer, size_t size)
+{
+ if (size < ZSTD_FRAMEIDSIZE) return 0;
+ { U32 const magic = MEM_readLE32(buffer);
+ if ((magic & ZSTD_MAGIC_SKIPPABLE_MASK) == ZSTD_MAGIC_SKIPPABLE_START) return 1;
+ }
+ return 0;
+}
+
/* ZSTD_frameHeaderSize_internal() :
* srcSize must be large enough to reach header size fields.
* note : only works for formats ZSTD_f_zstd1 and ZSTD_f_zstd1_magicless.
@@ -497,7 +513,6 @@ size_t ZSTD_getFrameHeader(ZSTD_frameHeader* zfhPtr, const void* src, size_t src
return ZSTD_getFrameHeader_advanced(zfhPtr, src, srcSize, ZSTD_f_zstd1);
}
-
/* ZSTD_getFrameContentSize() :
* compatible with legacy mode
* @return : decompressed size of the single frame pointed to be `src` if known, otherwise
@@ -532,6 +547,37 @@ static size_t readSkippableFrameSize(void const* src, size_t srcSize)
}
}
+/*! ZSTD_readSkippableFrame() :
+ * Retrieves a zstd skippable frame containing data given by src, and writes it to dst buffer.
+ *
+ * The parameter magicVariant will receive the magicVariant that was supplied when the frame was written,
+ * i.e. magicNumber - ZSTD_MAGIC_SKIPPABLE_START. This can be NULL if the caller is not interested
+ * in the magicVariant.
+ *
+ * Returns an error if destination buffer is not large enough, or if the frame is not skippable.
+ *
+ * @return : number of bytes written or a ZSTD error.
+ */
+ZSTDLIB_API size_t ZSTD_readSkippableFrame(void* dst, size_t dstCapacity, unsigned* magicVariant,
+ const void* src, size_t srcSize)
+{
+ U32 const magicNumber = MEM_readLE32(src);
+ size_t skippableFrameSize = readSkippableFrameSize(src, srcSize);
+ size_t skippableContentSize = skippableFrameSize - ZSTD_SKIPPABLEHEADERSIZE;
+
+ /* check input validity */
+ RETURN_ERROR_IF(!ZSTD_isSkippableFrame(src, srcSize), frameParameter_unsupported, "");
+ RETURN_ERROR_IF(skippableFrameSize < ZSTD_SKIPPABLEHEADERSIZE || skippableFrameSize > srcSize, srcSize_wrong, "");
+ RETURN_ERROR_IF(skippableContentSize > dstCapacity, dstSize_tooSmall, "");
+
+ /* deliver payload */
+ if (skippableContentSize > 0 && dst != NULL)
+ ZSTD_memcpy(dst, (const BYTE *)src + ZSTD_SKIPPABLEHEADERSIZE, skippableContentSize);
+ if (magicVariant != NULL)
+ *magicVariant = magicNumber - ZSTD_MAGIC_SKIPPABLE_START;
+ return skippableContentSize;
+}
+
/* ZSTD_findDecompressedSize() :
* compatible with legacy mode
* `srcSize` must be the exact length of some number of ZSTD compressed and/or
@@ -824,7 +870,7 @@ static size_t ZSTD_decompressFrame(ZSTD_DCtx* dctx,
switch(blockProperties.blockType)
{
case bt_compressed:
- decodedSize = ZSTD_decompressBlock_internal(dctx, op, (size_t)(oend-op), ip, cBlockSize, /* frame */ 1);
+ decodedSize = ZSTD_decompressBlock_internal(dctx, op, (size_t)(oend-op), ip, cBlockSize, /* frame */ 1, not_streaming);
break;
case bt_raw :
decodedSize = ZSTD_copyRawBlock(op, (size_t)(oend-op), ip, cBlockSize);
@@ -976,7 +1022,7 @@ size_t ZSTD_decompress(void* dst, size_t dstCapacity, const void* src, size_t sr
{
#if defined(ZSTD_HEAPMODE) && (ZSTD_HEAPMODE>=1)
size_t regenSize;
- ZSTD_DCtx* const dctx = ZSTD_createDCtx();
+ ZSTD_DCtx* const dctx = ZSTD_createDCtx_internal(ZSTD_defaultCMem);
RETURN_ERROR_IF(dctx==NULL, memory_allocation, "NULL pointer!");
regenSize = ZSTD_decompressDCtx(dctx, dst, dstCapacity, src, srcSize);
ZSTD_freeDCtx(dctx);
@@ -996,7 +1042,7 @@ size_t ZSTD_decompress(void* dst, size_t dstCapacity, const void* src, size_t sr
size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx* dctx) { return dctx->expected; }
/*
- * Similar to ZSTD_nextSrcSizeToDecompress(), but when when a block input can be streamed,
+ * Similar to ZSTD_nextSrcSizeToDecompress(), but when a block input can be streamed,
* we allow taking a partial block as the input. Currently only raw uncompressed blocks can
* be streamed.
*
@@ -1010,7 +1056,7 @@ static size_t ZSTD_nextSrcSizeToDecompressWithInputSize(ZSTD_DCtx* dctx, size_t
return dctx->expected;
if (dctx->bType != bt_raw)
return dctx->expected;
- return MIN(MAX(inputSize, 1), dctx->expected);
+ return BOUNDED(1, inputSize, dctx->expected);
}
ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx) {
@@ -1116,7 +1162,7 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, c
{
case bt_compressed:
DEBUGLOG(5, "ZSTD_decompressContinue: case bt_compressed");
- rSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize, /* frame */ 1);
+ rSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize, /* frame */ 1, is_streaming);
dctx->expected = 0; /* Streaming not supported */
break;
case bt_raw :
@@ -1438,7 +1484,7 @@ size_t ZSTD_decompress_usingDDict(ZSTD_DCtx* dctx,
ZSTD_DStream* ZSTD_createDStream(void)
{
DEBUGLOG(3, "ZSTD_createDStream");
- return ZSTD_createDStream_advanced(ZSTD_defaultCMem);
+ return ZSTD_createDCtx_internal(ZSTD_defaultCMem);
}
ZSTD_DStream* ZSTD_initStaticDStream(void *workspace, size_t workspaceSize)
@@ -1448,7 +1494,7 @@ ZSTD_DStream* ZSTD_initStaticDStream(void *workspace, size_t workspaceSize)
ZSTD_DStream* ZSTD_createDStream_advanced(ZSTD_customMem customMem)
{
- return ZSTD_createDCtx_advanced(customMem);
+ return ZSTD_createDCtx_internal(customMem);
}
size_t ZSTD_freeDStream(ZSTD_DStream* zds)
@@ -1708,7 +1754,8 @@ size_t ZSTD_sizeof_DStream(const ZSTD_DStream* dctx)
size_t ZSTD_decodingBufferSize_min(unsigned long long windowSize, unsigned long long frameContentSize)
{
size_t const blockSize = (size_t) MIN(windowSize, ZSTD_BLOCKSIZE_MAX);
- unsigned long long const neededRBSize = windowSize + blockSize + (WILDCOPY_OVERLENGTH * 2);
+ /* space is needed to store the litbuffer after the output of a given block without stomping the extDict of a previous run, as well as to cover both windows against wildcopy*/
+ unsigned long long const neededRBSize = windowSize + blockSize + ZSTD_BLOCKSIZE_MAX + (WILDCOPY_OVERLENGTH * 2);
unsigned long long const neededSize = MIN(frameContentSize, neededRBSize);
size_t const minRBSize = (size_t) neededSize;
RETURN_ERROR_IF((unsigned long long)minRBSize != neededSize,
@@ -1842,7 +1889,6 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB
DEBUGLOG(5, "stage zdss_init => transparent reset ");
zds->streamStage = zdss_loadHeader;
zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0;
- zds->legacyVersion = 0;
zds->hostageByte = 0;
zds->expectedOutBuffer = *output;
ZSTD_FALLTHROUGH;
diff --git a/lib/zstd/decompress/zstd_decompress_block.c b/lib/zstd/decompress/zstd_decompress_block.c
index 2d101d9a842e..c1913b8e7c89 100644
--- a/lib/zstd/decompress/zstd_decompress_block.c
+++ b/lib/zstd/decompress/zstd_decompress_block.c
@@ -69,15 +69,56 @@ size_t ZSTD_getcBlockSize(const void* src, size_t srcSize,
}
}
+/* Allocate buffer for literals, either overlapping current dst, or split between dst and litExtraBuffer, or stored entirely within litExtraBuffer */
+static void ZSTD_allocateLiteralsBuffer(ZSTD_DCtx* dctx, void* const dst, const size_t dstCapacity, const size_t litSize,
+ const streaming_operation streaming, const size_t expectedWriteSize, const unsigned splitImmediately)
+{
+ if (streaming == not_streaming && dstCapacity > ZSTD_BLOCKSIZE_MAX + WILDCOPY_OVERLENGTH + litSize + WILDCOPY_OVERLENGTH)
+ {
+ /* room for litbuffer to fit without read faulting */
+ dctx->litBuffer = (BYTE*)dst + ZSTD_BLOCKSIZE_MAX + WILDCOPY_OVERLENGTH;
+ dctx->litBufferEnd = dctx->litBuffer + litSize;
+ dctx->litBufferLocation = ZSTD_in_dst;
+ }
+ else if (litSize > ZSTD_LITBUFFEREXTRASIZE)
+ {
+ /* won't fit in litExtraBuffer, so it will be split between end of dst and extra buffer */
+ if (splitImmediately) {
+ /* won't fit in litExtraBuffer, so it will be split between end of dst and extra buffer */
+ dctx->litBuffer = (BYTE*)dst + expectedWriteSize - litSize + ZSTD_LITBUFFEREXTRASIZE - WILDCOPY_OVERLENGTH;
+ dctx->litBufferEnd = dctx->litBuffer + litSize - ZSTD_LITBUFFEREXTRASIZE;
+ }
+ else {
+ /* initially this will be stored entirely in dst during huffman decoding, it will partially shifted to litExtraBuffer after */
+ dctx->litBuffer = (BYTE*)dst + expectedWriteSize - litSize;
+ dctx->litBufferEnd = (BYTE*)dst + expectedWriteSize;
+ }
+ dctx->litBufferLocation = ZSTD_split;
+ }
+ else
+ {
+ /* fits entirely within litExtraBuffer, so no split is necessary */
+ dctx->litBuffer = dctx->litExtraBuffer;
+ dctx->litBufferEnd = dctx->litBuffer + litSize;
+ dctx->litBufferLocation = ZSTD_not_in_dst;
+ }
+}
/* Hidden declaration for fullbench */
size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
- const void* src, size_t srcSize);
+ const void* src, size_t srcSize,
+ void* dst, size_t dstCapacity, const streaming_operation streaming);
/*! ZSTD_decodeLiteralsBlock() :
+ * Where it is possible to do so without being stomped by the output during decompression, the literals block will be stored
+ * in the dstBuffer. If there is room to do so, it will be stored in full in the excess dst space after where the current
+ * block will be output. Otherwise it will be stored at the end of the current dst blockspace, with a small portion being
+ * stored in dctx->litExtraBuffer to help keep it "ahead" of the current output write.
+ *
* @return : nb of bytes read from src (< srcSize )
* note : symbol not declared but exposed for fullbench */
size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
- const void* src, size_t srcSize) /* note : srcSize < BLOCKSIZE */
+ const void* src, size_t srcSize, /* note : srcSize < BLOCKSIZE */
+ void* dst, size_t dstCapacity, const streaming_operation streaming)
{
DEBUGLOG(5, "ZSTD_decodeLiteralsBlock");
RETURN_ERROR_IF(srcSize < MIN_CBLOCK_SIZE, corruption_detected, "");
@@ -99,6 +140,7 @@ size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
U32 const lhlCode = (istart[0] >> 2) & 3;
U32 const lhc = MEM_readLE32(istart);
size_t hufSuccess;
+ size_t expectedWriteSize = MIN(ZSTD_BLOCKSIZE_MAX, dstCapacity);
switch(lhlCode)
{
case 0: case 1: default: /* note : default is impossible, since lhlCode into [0..3] */
@@ -121,8 +163,11 @@ size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
litCSize = (lhc >> 22) + ((size_t)istart[4] << 10);
break;
}
+ RETURN_ERROR_IF(litSize > 0 && dst == NULL, dstSize_tooSmall, "NULL not handled");
RETURN_ERROR_IF(litSize > ZSTD_BLOCKSIZE_MAX, corruption_detected, "");
RETURN_ERROR_IF(litCSize + lhSize > srcSize, corruption_detected, "");
+ RETURN_ERROR_IF(expectedWriteSize < litSize , dstSize_tooSmall, "");
+ ZSTD_allocateLiteralsBuffer(dctx, dst, dstCapacity, litSize, streaming, expectedWriteSize, 0);
/* prefetch huffman table if cold */
if (dctx->ddictIsCold && (litSize > 768 /* heuristic */)) {
@@ -133,11 +178,11 @@ size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
if (singleStream) {
hufSuccess = HUF_decompress1X_usingDTable_bmi2(
dctx->litBuffer, litSize, istart+lhSize, litCSize,
- dctx->HUFptr, dctx->bmi2);
+ dctx->HUFptr, ZSTD_DCtx_get_bmi2(dctx));
} else {
hufSuccess = HUF_decompress4X_usingDTable_bmi2(
dctx->litBuffer, litSize, istart+lhSize, litCSize,
- dctx->HUFptr, dctx->bmi2);
+ dctx->HUFptr, ZSTD_DCtx_get_bmi2(dctx));
}
} else {
if (singleStream) {
@@ -150,15 +195,22 @@ size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
hufSuccess = HUF_decompress1X1_DCtx_wksp_bmi2(
dctx->entropy.hufTable, dctx->litBuffer, litSize,
istart+lhSize, litCSize, dctx->workspace,
- sizeof(dctx->workspace), dctx->bmi2);
+ sizeof(dctx->workspace), ZSTD_DCtx_get_bmi2(dctx));
#endif
} else {
hufSuccess = HUF_decompress4X_hufOnly_wksp_bmi2(
dctx->entropy.hufTable, dctx->litBuffer, litSize,
istart+lhSize, litCSize, dctx->workspace,
- sizeof(dctx->workspace), dctx->bmi2);
+ sizeof(dctx->workspace), ZSTD_DCtx_get_bmi2(dctx));
}
}
+ if (dctx->litBufferLocation == ZSTD_split)
+ {
+ ZSTD_memcpy(dctx->litExtraBuffer, dctx->litBufferEnd - ZSTD_LITBUFFEREXTRASIZE, ZSTD_LITBUFFEREXTRASIZE);
+ ZSTD_memmove(dctx->litBuffer + ZSTD_LITBUFFEREXTRASIZE - WILDCOPY_OVERLENGTH, dctx->litBuffer, litSize - ZSTD_LITBUFFEREXTRASIZE);
+ dctx->litBuffer += ZSTD_LITBUFFEREXTRASIZE - WILDCOPY_OVERLENGTH;
+ dctx->litBufferEnd -= WILDCOPY_OVERLENGTH;
+ }
RETURN_ERROR_IF(HUF_isError(hufSuccess), corruption_detected, "");
@@ -166,13 +218,13 @@ size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
dctx->litSize = litSize;
dctx->litEntropy = 1;
if (litEncType==set_compressed) dctx->HUFptr = dctx->entropy.hufTable;
- ZSTD_memset(dctx->litBuffer + dctx->litSize, 0, WILDCOPY_OVERLENGTH);
return litCSize + lhSize;
}
case set_basic:
{ size_t litSize, lhSize;
U32 const lhlCode = ((istart[0]) >> 2) & 3;
+ size_t expectedWriteSize = MIN(ZSTD_BLOCKSIZE_MAX, dstCapacity);
switch(lhlCode)
{
case 0: case 2: default: /* note : default is impossible, since lhlCode into [0..3] */
@@ -189,23 +241,36 @@ size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
break;
}
+ RETURN_ERROR_IF(litSize > 0 && dst == NULL, dstSize_tooSmall, "NULL not handled");
+ RETURN_ERROR_IF(expectedWriteSize < litSize, dstSize_tooSmall, "");
+ ZSTD_allocateLiteralsBuffer(dctx, dst, dstCapacity, litSize, streaming, expectedWriteSize, 1);
if (lhSize+litSize+WILDCOPY_OVERLENGTH > srcSize) { /* risk reading beyond src buffer with wildcopy */
RETURN_ERROR_IF(litSize+lhSize > srcSize, corruption_detected, "");
- ZSTD_memcpy(dctx->litBuffer, istart+lhSize, litSize);
+ if (dctx->litBufferLocation == ZSTD_split)
+ {
+ ZSTD_memcpy(dctx->litBuffer, istart + lhSize, litSize - ZSTD_LITBUFFEREXTRASIZE);
+ ZSTD_memcpy(dctx->litExtraBuffer, istart + lhSize + litSize - ZSTD_LITBUFFEREXTRASIZE, ZSTD_LITBUFFEREXTRASIZE);
+ }
+ else
+ {
+ ZSTD_memcpy(dctx->litBuffer, istart + lhSize, litSize);
+ }
dctx->litPtr = dctx->litBuffer;
dctx->litSize = litSize;
- ZSTD_memset(dctx->litBuffer + dctx->litSize, 0, WILDCOPY_OVERLENGTH);
return lhSize+litSize;
}
/* direct reference into compressed stream */
dctx->litPtr = istart+lhSize;
dctx->litSize = litSize;
+ dctx->litBufferEnd = dctx->litPtr + litSize;
+ dctx->litBufferLocation = ZSTD_not_in_dst;
return lhSize+litSize;
}
case set_rle:
{ U32 const lhlCode = ((istart[0]) >> 2) & 3;
size_t litSize, lhSize;
+ size_t expectedWriteSize = MIN(ZSTD_BLOCKSIZE_MAX, dstCapacity);
switch(lhlCode)
{
case 0: case 2: default: /* note : default is impossible, since lhlCode into [0..3] */
@@ -222,8 +287,19 @@ size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
RETURN_ERROR_IF(srcSize<4, corruption_detected, "srcSize >= MIN_CBLOCK_SIZE == 3; here we need lhSize+1 = 4");
break;
}
+ RETURN_ERROR_IF(litSize > 0 && dst == NULL, dstSize_tooSmall, "NULL not handled");
RETURN_ERROR_IF(litSize > ZSTD_BLOCKSIZE_MAX, corruption_detected, "");
- ZSTD_memset(dctx->litBuffer, istart[lhSize], litSize + WILDCOPY_OVERLENGTH);
+ RETURN_ERROR_IF(expectedWriteSize < litSize, dstSize_tooSmall, "");
+ ZSTD_allocateLiteralsBuffer(dctx, dst, dstCapacity, litSize, streaming, expectedWriteSize, 1);
+ if (dctx->litBufferLocation == ZSTD_split)
+ {
+ ZSTD_memset(dctx->litBuffer, istart[lhSize], litSize - ZSTD_LITBUFFEREXTRASIZE);
+ ZSTD_memset(dctx->litExtraBuffer, istart[lhSize], ZSTD_LITBUFFEREXTRASIZE);
+ }
+ else
+ {
+ ZSTD_memset(dctx->litBuffer, istart[lhSize], litSize);
+ }
dctx->litPtr = dctx->litBuffer;
dctx->litSize = litSize;
return lhSize+1;
@@ -343,7 +419,7 @@ static const ZSTD_seqSymbol ML_defaultDTable[(1<<ML_DEFAULTNORMLOG)+1] = {
}; /* ML_defaultDTable */
-static void ZSTD_buildSeqTable_rle(ZSTD_seqSymbol* dt, U32 baseValue, U32 nbAddBits)
+static void ZSTD_buildSeqTable_rle(ZSTD_seqSymbol* dt, U32 baseValue, U8 nbAddBits)
{
void* ptr = dt;
ZSTD_seqSymbol_header* const DTableH = (ZSTD_seqSymbol_header*)ptr;
@@ -355,7 +431,7 @@ static void ZSTD_buildSeqTable_rle(ZSTD_seqSymbol* dt, U32 baseValue, U32 nbAddB
cell->nbBits = 0;
cell->nextState = 0;
assert(nbAddBits < 255);
- cell->nbAdditionalBits = (BYTE)nbAddBits;
+ cell->nbAdditionalBits = nbAddBits;
cell->baseValue = baseValue;
}
@@ -367,7 +443,7 @@ static void ZSTD_buildSeqTable_rle(ZSTD_seqSymbol* dt, U32 baseValue, U32 nbAddB
FORCE_INLINE_TEMPLATE
void ZSTD_buildFSETable_body(ZSTD_seqSymbol* dt,
const short* normalizedCounter, unsigned maxSymbolValue,
- const U32* baseValue, const U32* nbAdditionalBits,
+ const U32* baseValue, const U8* nbAdditionalBits,
unsigned tableLog, void* wksp, size_t wkspSize)
{
ZSTD_seqSymbol* const tableDecode = dt+1;
@@ -478,7 +554,7 @@ void ZSTD_buildFSETable_body(ZSTD_seqSymbol* dt,
tableDecode[u].nbBits = (BYTE) (tableLog - BIT_highbit32(nextState) );
tableDecode[u].nextState = (U16) ( (nextState << tableDecode[u].nbBits) - tableSize);
assert(nbAdditionalBits[symbol] < 255);
- tableDecode[u].nbAdditionalBits = (BYTE)nbAdditionalBits[symbol];
+ tableDecode[u].nbAdditionalBits = nbAdditionalBits[symbol];
tableDecode[u].baseValue = baseValue[symbol];
}
}
@@ -487,7 +563,7 @@ void ZSTD_buildFSETable_body(ZSTD_seqSymbol* dt,
/* Avoids the FORCE_INLINE of the _body() function. */
static void ZSTD_buildFSETable_body_default(ZSTD_seqSymbol* dt,
const short* normalizedCounter, unsigned maxSymbolValue,
- const U32* baseValue, const U32* nbAdditionalBits,
+ const U32* baseValue, const U8* nbAdditionalBits,
unsigned tableLog, void* wksp, size_t wkspSize)
{
ZSTD_buildFSETable_body(dt, normalizedCounter, maxSymbolValue,
@@ -495,9 +571,9 @@ static void ZSTD_buildFSETable_body_default(ZSTD_seqSymbol* dt,
}
#if DYNAMIC_BMI2
-TARGET_ATTRIBUTE("bmi2") static void ZSTD_buildFSETable_body_bmi2(ZSTD_seqSymbol* dt,
+BMI2_TARGET_ATTRIBUTE static void ZSTD_buildFSETable_body_bmi2(ZSTD_seqSymbol* dt,
const short* normalizedCounter, unsigned maxSymbolValue,
- const U32* baseValue, const U32* nbAdditionalBits,
+ const U32* baseValue, const U8* nbAdditionalBits,
unsigned tableLog, void* wksp, size_t wkspSize)
{
ZSTD_buildFSETable_body(dt, normalizedCounter, maxSymbolValue,
@@ -507,7 +583,7 @@ TARGET_ATTRIBUTE("bmi2") static void ZSTD_buildFSETable_body_bmi2(ZSTD_seqSymbol
void ZSTD_buildFSETable(ZSTD_seqSymbol* dt,
const short* normalizedCounter, unsigned maxSymbolValue,
- const U32* baseValue, const U32* nbAdditionalBits,
+ const U32* baseValue, const U8* nbAdditionalBits,
unsigned tableLog, void* wksp, size_t wkspSize, int bmi2)
{
#if DYNAMIC_BMI2
@@ -529,7 +605,7 @@ void ZSTD_buildFSETable(ZSTD_seqSymbol* dt,
static size_t ZSTD_buildSeqTable(ZSTD_seqSymbol* DTableSpace, const ZSTD_seqSymbol** DTablePtr,
symbolEncodingType_e type, unsigned max, U32 maxLog,
const void* src, size_t srcSize,
- const U32* baseValue, const U32* nbAdditionalBits,
+ const U32* baseValue, const U8* nbAdditionalBits,
const ZSTD_seqSymbol* defaultTable, U32 flagRepeatTable,
int ddictIsCold, int nbSeq, U32* wksp, size_t wkspSize,
int bmi2)
@@ -541,7 +617,7 @@ static size_t ZSTD_buildSeqTable(ZSTD_seqSymbol* DTableSpace, const ZSTD_seqSymb
RETURN_ERROR_IF((*(const BYTE*)src) > max, corruption_detected, "");
{ U32 const symbol = *(const BYTE*)src;
U32 const baseline = baseValue[symbol];
- U32 const nbBits = nbAdditionalBits[symbol];
+ U8 const nbBits = nbAdditionalBits[symbol];
ZSTD_buildSeqTable_rle(DTableSpace, baseline, nbBits);
}
*DTablePtr = DTableSpace;
@@ -620,7 +696,7 @@ size_t ZSTD_decodeSeqHeaders(ZSTD_DCtx* dctx, int* nbSeqPtr,
LL_defaultDTable, dctx->fseEntropy,
dctx->ddictIsCold, nbSeq,
dctx->workspace, sizeof(dctx->workspace),
- dctx->bmi2);
+ ZSTD_DCtx_get_bmi2(dctx));
RETURN_ERROR_IF(ZSTD_isError(llhSize), corruption_detected, "ZSTD_buildSeqTable failed");
ip += llhSize;
}
@@ -632,7 +708,7 @@ size_t ZSTD_decodeSeqHeaders(ZSTD_DCtx* dctx, int* nbSeqPtr,
OF_defaultDTable, dctx->fseEntropy,
dctx->ddictIsCold, nbSeq,
dctx->workspace, sizeof(dctx->workspace),
- dctx->bmi2);
+ ZSTD_DCtx_get_bmi2(dctx));
RETURN_ERROR_IF(ZSTD_isError(ofhSize), corruption_detected, "ZSTD_buildSeqTable failed");
ip += ofhSize;
}
@@ -644,7 +720,7 @@ size_t ZSTD_decodeSeqHeaders(ZSTD_DCtx* dctx, int* nbSeqPtr,
ML_defaultDTable, dctx->fseEntropy,
dctx->ddictIsCold, nbSeq,
dctx->workspace, sizeof(dctx->workspace),
- dctx->bmi2);
+ ZSTD_DCtx_get_bmi2(dctx));
RETURN_ERROR_IF(ZSTD_isError(mlhSize), corruption_detected, "ZSTD_buildSeqTable failed");
ip += mlhSize;
}
@@ -658,7 +734,6 @@ typedef struct {
size_t litLength;
size_t matchLength;
size_t offset;
- const BYTE* match;
} seq_t;
typedef struct {
@@ -672,9 +747,6 @@ typedef struct {
ZSTD_fseState stateOffb;
ZSTD_fseState stateML;
size_t prevOffset[ZSTD_REP_NUM];
- const BYTE* prefixStart;
- const BYTE* dictEnd;
- size_t pos;
} seqState_t;
/*! ZSTD_overlapCopy8() :
@@ -717,7 +789,7 @@ HINT_INLINE void ZSTD_overlapCopy8(BYTE** op, BYTE const** ip, size_t offset) {
* - ZSTD_overlap_src_before_dst: The src and dst may overlap and may be any distance apart.
* The src buffer must be before the dst buffer.
*/
-static void ZSTD_safecopy(BYTE* op, BYTE* const oend_w, BYTE const* ip, ptrdiff_t length, ZSTD_overlap_e ovtype) {
+static void ZSTD_safecopy(BYTE* op, const BYTE* const oend_w, BYTE const* ip, ptrdiff_t length, ZSTD_overlap_e ovtype) {
ptrdiff_t const diff = op - ip;
BYTE* const oend = op + length;
@@ -733,6 +805,7 @@ static void ZSTD_safecopy(BYTE* op, BYTE* const oend_w, BYTE const* ip, ptrdiff_
/* Copy 8 bytes and ensure the offset >= 8 when there can be overlap. */
assert(length >= 8);
ZSTD_overlapCopy8(&op, &ip, diff);
+ length -= 8;
assert(op - ip >= 8);
assert(op <= oend);
}
@@ -747,8 +820,31 @@ static void ZSTD_safecopy(BYTE* op, BYTE* const oend_w, BYTE const* ip, ptrdiff_
assert(oend > oend_w);
ZSTD_wildcopy(op, ip, oend_w - op, ovtype);
ip += oend_w - op;
- op = oend_w;
+ op += oend_w - op;
+ }
+ /* Handle the leftovers. */
+ while (op < oend) *op++ = *ip++;
+}
+
+/* ZSTD_safecopyDstBeforeSrc():
+ * This version allows overlap with dst before src, or handles the non-overlap case with dst after src
+ * Kept separate from more common ZSTD_safecopy case to avoid performance impact to the safecopy common case */
+static void ZSTD_safecopyDstBeforeSrc(BYTE* op, BYTE const* ip, ptrdiff_t length) {
+ ptrdiff_t const diff = op - ip;
+ BYTE* const oend = op + length;
+
+ if (length < 8 || diff > -8) {
+ /* Handle short lengths, close overlaps, and dst not before src. */
+ while (op < oend) *op++ = *ip++;
+ return;
+ }
+
+ if (op <= oend - WILDCOPY_OVERLENGTH && diff < -WILDCOPY_VECLEN) {
+ ZSTD_wildcopy(op, ip, oend - WILDCOPY_OVERLENGTH - op, ZSTD_no_overlap);
+ ip += oend - WILDCOPY_OVERLENGTH - op;
+ op += oend - WILDCOPY_OVERLENGTH - op;
}
+
/* Handle the leftovers. */
while (op < oend) *op++ = *ip++;
}
@@ -763,9 +859,9 @@ static void ZSTD_safecopy(BYTE* op, BYTE* const oend_w, BYTE const* ip, ptrdiff_
*/
FORCE_NOINLINE
size_t ZSTD_execSequenceEnd(BYTE* op,
- BYTE* const oend, seq_t sequence,
- const BYTE** litPtr, const BYTE* const litLimit,
- const BYTE* const prefixStart, const BYTE* const virtualStart, const BYTE* const dictEnd)
+ BYTE* const oend, seq_t sequence,
+ const BYTE** litPtr, const BYTE* const litLimit,
+ const BYTE* const prefixStart, const BYTE* const virtualStart, const BYTE* const dictEnd)
{
BYTE* const oLitEnd = op + sequence.litLength;
size_t const sequenceLength = sequence.litLength + sequence.matchLength;
@@ -788,27 +884,76 @@ size_t ZSTD_execSequenceEnd(BYTE* op,
if (sequence.offset > (size_t)(oLitEnd - prefixStart)) {
/* offset beyond prefix */
RETURN_ERROR_IF(sequence.offset > (size_t)(oLitEnd - virtualStart), corruption_detected, "");
- match = dictEnd - (prefixStart-match);
+ match = dictEnd - (prefixStart - match);
if (match + sequence.matchLength <= dictEnd) {
ZSTD_memmove(oLitEnd, match, sequence.matchLength);
return sequenceLength;
}
/* span extDict & currentPrefixSegment */
{ size_t const length1 = dictEnd - match;
- ZSTD_memmove(oLitEnd, match, length1);
- op = oLitEnd + length1;
- sequence.matchLength -= length1;
- match = prefixStart;
- } }
+ ZSTD_memmove(oLitEnd, match, length1);
+ op = oLitEnd + length1;
+ sequence.matchLength -= length1;
+ match = prefixStart;
+ }
+ }
+ ZSTD_safecopy(op, oend_w, match, sequence.matchLength, ZSTD_overlap_src_before_dst);
+ return sequenceLength;
+}
+
+/* ZSTD_execSequenceEndSplitLitBuffer():
+ * This version is intended to be used during instances where the litBuffer is still split. It is kept separate to avoid performance impact for the good case.
+ */
+FORCE_NOINLINE
+size_t ZSTD_execSequenceEndSplitLitBuffer(BYTE* op,
+ BYTE* const oend, const BYTE* const oend_w, seq_t sequence,
+ const BYTE** litPtr, const BYTE* const litLimit,
+ const BYTE* const prefixStart, const BYTE* const virtualStart, const BYTE* const dictEnd)
+{
+ BYTE* const oLitEnd = op + sequence.litLength;
+ size_t const sequenceLength = sequence.litLength + sequence.matchLength;
+ const BYTE* const iLitEnd = *litPtr + sequence.litLength;
+ const BYTE* match = oLitEnd - sequence.offset;
+
+
+ /* bounds checks : careful of address space overflow in 32-bit mode */
+ RETURN_ERROR_IF(sequenceLength > (size_t)(oend - op), dstSize_tooSmall, "last match must fit within dstBuffer");
+ RETURN_ERROR_IF(sequence.litLength > (size_t)(litLimit - *litPtr), corruption_detected, "try to read beyond literal buffer");
+ assert(op < op + sequenceLength);
+ assert(oLitEnd < op + sequenceLength);
+
+ /* copy literals */
+ RETURN_ERROR_IF(op > *litPtr && op < *litPtr + sequence.litLength, dstSize_tooSmall, "output should not catch up to and overwrite literal buffer");
+ ZSTD_safecopyDstBeforeSrc(op, *litPtr, sequence.litLength);
+ op = oLitEnd;
+ *litPtr = iLitEnd;
+
+ /* copy Match */
+ if (sequence.offset > (size_t)(oLitEnd - prefixStart)) {
+ /* offset beyond prefix */
+ RETURN_ERROR_IF(sequence.offset > (size_t)(oLitEnd - virtualStart), corruption_detected, "");
+ match = dictEnd - (prefixStart - match);
+ if (match + sequence.matchLength <= dictEnd) {
+ ZSTD_memmove(oLitEnd, match, sequence.matchLength);
+ return sequenceLength;
+ }
+ /* span extDict & currentPrefixSegment */
+ { size_t const length1 = dictEnd - match;
+ ZSTD_memmove(oLitEnd, match, length1);
+ op = oLitEnd + length1;
+ sequence.matchLength -= length1;
+ match = prefixStart;
+ }
+ }
ZSTD_safecopy(op, oend_w, match, sequence.matchLength, ZSTD_overlap_src_before_dst);
return sequenceLength;
}
HINT_INLINE
size_t ZSTD_execSequence(BYTE* op,
- BYTE* const oend, seq_t sequence,
- const BYTE** litPtr, const BYTE* const litLimit,
- const BYTE* const prefixStart, const BYTE* const virtualStart, const BYTE* const dictEnd)
+ BYTE* const oend, seq_t sequence,
+ const BYTE** litPtr, const BYTE* const litLimit,
+ const BYTE* const prefixStart, const BYTE* const virtualStart, const BYTE* const dictEnd)
{
BYTE* const oLitEnd = op + sequence.litLength;
size_t const sequenceLength = sequence.litLength + sequence.matchLength;
@@ -825,10 +970,102 @@ size_t ZSTD_execSequence(BYTE* op,
* - 32-bit mode and the match length overflows
*/
if (UNLIKELY(
+ iLitEnd > litLimit ||
+ oMatchEnd > oend_w ||
+ (MEM_32bits() && (size_t)(oend - op) < sequenceLength + WILDCOPY_OVERLENGTH)))
+ return ZSTD_execSequenceEnd(op, oend, sequence, litPtr, litLimit, prefixStart, virtualStart, dictEnd);
+
+ /* Assumptions (everything else goes into ZSTD_execSequenceEnd()) */
+ assert(op <= oLitEnd /* No overflow */);
+ assert(oLitEnd < oMatchEnd /* Non-zero match & no overflow */);
+ assert(oMatchEnd <= oend /* No underflow */);
+ assert(iLitEnd <= litLimit /* Literal length is in bounds */);
+ assert(oLitEnd <= oend_w /* Can wildcopy literals */);
+ assert(oMatchEnd <= oend_w /* Can wildcopy matches */);
+
+ /* Copy Literals:
+ * Split out litLength <= 16 since it is nearly always true. +1.6% on gcc-9.
+ * We likely don't need the full 32-byte wildcopy.
+ */
+ assert(WILDCOPY_OVERLENGTH >= 16);
+ ZSTD_copy16(op, (*litPtr));
+ if (UNLIKELY(sequence.litLength > 16)) {
+ ZSTD_wildcopy(op + 16, (*litPtr) + 16, sequence.litLength - 16, ZSTD_no_overlap);
+ }
+ op = oLitEnd;
+ *litPtr = iLitEnd; /* update for next sequence */
+
+ /* Copy Match */
+ if (sequence.offset > (size_t)(oLitEnd - prefixStart)) {
+ /* offset beyond prefix -> go into extDict */
+ RETURN_ERROR_IF(UNLIKELY(sequence.offset > (size_t)(oLitEnd - virtualStart)), corruption_detected, "");
+ match = dictEnd + (match - prefixStart);
+ if (match + sequence.matchLength <= dictEnd) {
+ ZSTD_memmove(oLitEnd, match, sequence.matchLength);
+ return sequenceLength;
+ }
+ /* span extDict & currentPrefixSegment */
+ { size_t const length1 = dictEnd - match;
+ ZSTD_memmove(oLitEnd, match, length1);
+ op = oLitEnd + length1;
+ sequence.matchLength -= length1;
+ match = prefixStart;
+ }
+ }
+ /* Match within prefix of 1 or more bytes */
+ assert(op <= oMatchEnd);
+ assert(oMatchEnd <= oend_w);
+ assert(match >= prefixStart);
+ assert(sequence.matchLength >= 1);
+
+ /* Nearly all offsets are >= WILDCOPY_VECLEN bytes, which means we can use wildcopy
+ * without overlap checking.
+ */
+ if (LIKELY(sequence.offset >= WILDCOPY_VECLEN)) {
+ /* We bet on a full wildcopy for matches, since we expect matches to be
+ * longer than literals (in general). In silesia, ~10% of matches are longer
+ * than 16 bytes.
+ */
+ ZSTD_wildcopy(op, match, (ptrdiff_t)sequence.matchLength, ZSTD_no_overlap);
+ return sequenceLength;
+ }
+ assert(sequence.offset < WILDCOPY_VECLEN);
+
+ /* Copy 8 bytes and spread the offset to be >= 8. */
+ ZSTD_overlapCopy8(&op, &match, sequence.offset);
+
+ /* If the match length is > 8 bytes, then continue with the wildcopy. */
+ if (sequence.matchLength > 8) {
+ assert(op < oMatchEnd);
+ ZSTD_wildcopy(op, match, (ptrdiff_t)sequence.matchLength - 8, ZSTD_overlap_src_before_dst);
+ }
+ return sequenceLength;
+}
+
+HINT_INLINE
+size_t ZSTD_execSequenceSplitLitBuffer(BYTE* op,
+ BYTE* const oend, const BYTE* const oend_w, seq_t sequence,
+ const BYTE** litPtr, const BYTE* const litLimit,
+ const BYTE* const prefixStart, const BYTE* const virtualStart, const BYTE* const dictEnd)
+{
+ BYTE* const oLitEnd = op + sequence.litLength;
+ size_t const sequenceLength = sequence.litLength + sequence.matchLength;
+ BYTE* const oMatchEnd = op + sequenceLength; /* risk : address space overflow (32-bits) */
+ const BYTE* const iLitEnd = *litPtr + sequence.litLength;
+ const BYTE* match = oLitEnd - sequence.offset;
+
+ assert(op != NULL /* Precondition */);
+ assert(oend_w < oend /* No underflow */);
+ /* Handle edge cases in a slow path:
+ * - Read beyond end of literals
+ * - Match end is within WILDCOPY_OVERLIMIT of oend
+ * - 32-bit mode and the match length overflows
+ */
+ if (UNLIKELY(
iLitEnd > litLimit ||
oMatchEnd > oend_w ||
(MEM_32bits() && (size_t)(oend - op) < sequenceLength + WILDCOPY_OVERLENGTH)))
- return ZSTD_execSequenceEnd(op, oend, sequence, litPtr, litLimit, prefixStart, virtualStart, dictEnd);
+ return ZSTD_execSequenceEndSplitLitBuffer(op, oend, oend_w, sequence, litPtr, litLimit, prefixStart, virtualStart, dictEnd);
/* Assumptions (everything else goes into ZSTD_execSequenceEnd()) */
assert(op <= oLitEnd /* No overflow */);
@@ -896,6 +1133,7 @@ size_t ZSTD_execSequence(BYTE* op,
return sequenceLength;
}
+
static void
ZSTD_initFseState(ZSTD_fseState* DStatePtr, BIT_DStream_t* bitD, const ZSTD_seqSymbol* dt)
{
@@ -909,20 +1147,10 @@ ZSTD_initFseState(ZSTD_fseState* DStatePtr, BIT_DStream_t* bitD, const ZSTD_seqS
}
FORCE_INLINE_TEMPLATE void
-ZSTD_updateFseState(ZSTD_fseState* DStatePtr, BIT_DStream_t* bitD)
-{
- ZSTD_seqSymbol const DInfo = DStatePtr->table[DStatePtr->state];
- U32 const nbBits = DInfo.nbBits;
- size_t const lowBits = BIT_readBits(bitD, nbBits);
- DStatePtr->state = DInfo.nextState + lowBits;
-}
-
-FORCE_INLINE_TEMPLATE void
-ZSTD_updateFseStateWithDInfo(ZSTD_fseState* DStatePtr, BIT_DStream_t* bitD, ZSTD_seqSymbol const DInfo)
+ZSTD_updateFseStateWithDInfo(ZSTD_fseState* DStatePtr, BIT_DStream_t* bitD, U16 nextState, U32 nbBits)
{
- U32 const nbBits = DInfo.nbBits;
size_t const lowBits = BIT_readBits(bitD, nbBits);
- DStatePtr->state = DInfo.nextState + lowBits;
+ DStatePtr->state = nextState + lowBits;
}
/* We need to add at most (ZSTD_WINDOWLOG_MAX_32 - 1) bits to read the maximum
@@ -936,116 +1164,105 @@ ZSTD_updateFseStateWithDInfo(ZSTD_fseState* DStatePtr, BIT_DStream_t* bitD, ZSTD
: 0)
typedef enum { ZSTD_lo_isRegularOffset, ZSTD_lo_isLongOffset=1 } ZSTD_longOffset_e;
-typedef enum { ZSTD_p_noPrefetch=0, ZSTD_p_prefetch=1 } ZSTD_prefetch_e;
FORCE_INLINE_TEMPLATE seq_t
-ZSTD_decodeSequence(seqState_t* seqState, const ZSTD_longOffset_e longOffsets, const ZSTD_prefetch_e prefetch)
+ZSTD_decodeSequence(seqState_t* seqState, const ZSTD_longOffset_e longOffsets)
{
seq_t seq;
- ZSTD_seqSymbol const llDInfo = seqState->stateLL.table[seqState->stateLL.state];
- ZSTD_seqSymbol const mlDInfo = seqState->stateML.table[seqState->stateML.state];
- ZSTD_seqSymbol const ofDInfo = seqState->stateOffb.table[seqState->stateOffb.state];
- U32 const llBase = llDInfo.baseValue;
- U32 const mlBase = mlDInfo.baseValue;
- U32 const ofBase = ofDInfo.baseValue;
- BYTE const llBits = llDInfo.nbAdditionalBits;
- BYTE const mlBits = mlDInfo.nbAdditionalBits;
- BYTE const ofBits = ofDInfo.nbAdditionalBits;
- BYTE const totalBits = llBits+mlBits+ofBits;
-
- /* sequence */
- { size_t offset;
- if (ofBits > 1) {
- ZSTD_STATIC_ASSERT(ZSTD_lo_isLongOffset == 1);
- ZSTD_STATIC_ASSERT(LONG_OFFSETS_MAX_EXTRA_BITS_32 == 5);
- assert(ofBits <= MaxOff);
- if (MEM_32bits() && longOffsets && (ofBits >= STREAM_ACCUMULATOR_MIN_32)) {
- U32 const extraBits = ofBits - MIN(ofBits, 32 - seqState->DStream.bitsConsumed);
- offset = ofBase + (BIT_readBitsFast(&seqState->DStream, ofBits - extraBits) << extraBits);
- BIT_reloadDStream(&seqState->DStream);
- if (extraBits) offset += BIT_readBitsFast(&seqState->DStream, extraBits);
- assert(extraBits <= LONG_OFFSETS_MAX_EXTRA_BITS_32); /* to avoid another reload */
- } else {
- offset = ofBase + BIT_readBitsFast(&seqState->DStream, ofBits/*>0*/); /* <= (ZSTD_WINDOWLOG_MAX-1) bits */
- if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream);
- }
- seqState->prevOffset[2] = seqState->prevOffset[1];
- seqState->prevOffset[1] = seqState->prevOffset[0];
- seqState->prevOffset[0] = offset;
- } else {
- U32 const ll0 = (llBase == 0);
- if (LIKELY((ofBits == 0))) {
- if (LIKELY(!ll0))
- offset = seqState->prevOffset[0];
- else {
- offset = seqState->prevOffset[1];
- seqState->prevOffset[1] = seqState->prevOffset[0];
- seqState->prevOffset[0] = offset;
+ const ZSTD_seqSymbol* const llDInfo = seqState->stateLL.table + seqState->stateLL.state;
+ const ZSTD_seqSymbol* const mlDInfo = seqState->stateML.table + seqState->stateML.state;
+ const ZSTD_seqSymbol* const ofDInfo = seqState->stateOffb.table + seqState->stateOffb.state;
+ seq.matchLength = mlDInfo->baseValue;
+ seq.litLength = llDInfo->baseValue;
+ { U32 const ofBase = ofDInfo->baseValue;
+ BYTE const llBits = llDInfo->nbAdditionalBits;
+ BYTE const mlBits = mlDInfo->nbAdditionalBits;
+ BYTE const ofBits = ofDInfo->nbAdditionalBits;
+ BYTE const totalBits = llBits+mlBits+ofBits;
+
+ U16 const llNext = llDInfo->nextState;
+ U16 const mlNext = mlDInfo->nextState;
+ U16 const ofNext = ofDInfo->nextState;
+ U32 const llnbBits = llDInfo->nbBits;
+ U32 const mlnbBits = mlDInfo->nbBits;
+ U32 const ofnbBits = ofDInfo->nbBits;
+ /*
+ * As gcc has better branch and block analyzers, sometimes it is only
+ * valuable to mark likelyness for clang, it gives around 3-4% of
+ * performance.
+ */
+
+ /* sequence */
+ { size_t offset;
+ #if defined(__clang__)
+ if (LIKELY(ofBits > 1)) {
+ #else
+ if (ofBits > 1) {
+ #endif
+ ZSTD_STATIC_ASSERT(ZSTD_lo_isLongOffset == 1);
+ ZSTD_STATIC_ASSERT(LONG_OFFSETS_MAX_EXTRA_BITS_32 == 5);
+ assert(ofBits <= MaxOff);
+ if (MEM_32bits() && longOffsets && (ofBits >= STREAM_ACCUMULATOR_MIN_32)) {
+ U32 const extraBits = ofBits - MIN(ofBits, 32 - seqState->DStream.bitsConsumed);
+ offset = ofBase + (BIT_readBitsFast(&seqState->DStream, ofBits - extraBits) << extraBits);
+ BIT_reloadDStream(&seqState->DStream);
+ if (extraBits) offset += BIT_readBitsFast(&seqState->DStream, extraBits);
+ assert(extraBits <= LONG_OFFSETS_MAX_EXTRA_BITS_32); /* to avoid another reload */
+ } else {
+ offset = ofBase + BIT_readBitsFast(&seqState->DStream, ofBits/*>0*/); /* <= (ZSTD_WINDOWLOG_MAX-1) bits */
+ if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream);
}
+ seqState->prevOffset[2] = seqState->prevOffset[1];
+ seqState->prevOffset[1] = seqState->prevOffset[0];
+ seqState->prevOffset[0] = offset;
} else {
- offset = ofBase + ll0 + BIT_readBitsFast(&seqState->DStream, 1);
- { size_t temp = (offset==3) ? seqState->prevOffset[0] - 1 : seqState->prevOffset[offset];
- temp += !temp; /* 0 is not valid; input is corrupted; force offset to 1 */
- if (offset != 1) seqState->prevOffset[2] = seqState->prevOffset[1];
- seqState->prevOffset[1] = seqState->prevOffset[0];
- seqState->prevOffset[0] = offset = temp;
- } } }
- seq.offset = offset;
- }
-
- seq.matchLength = mlBase;
- if (mlBits > 0)
- seq.matchLength += BIT_readBitsFast(&seqState->DStream, mlBits/*>0*/);
-
- if (MEM_32bits() && (mlBits+llBits >= STREAM_ACCUMULATOR_MIN_32-LONG_OFFSETS_MAX_EXTRA_BITS_32))
- BIT_reloadDStream(&seqState->DStream);
- if (MEM_64bits() && UNLIKELY(totalBits >= STREAM_ACCUMULATOR_MIN_64-(LLFSELog+MLFSELog+OffFSELog)))
- BIT_reloadDStream(&seqState->DStream);
- /* Ensure there are enough bits to read the rest of data in 64-bit mode. */
- ZSTD_STATIC_ASSERT(16+LLFSELog+MLFSELog+OffFSELog < STREAM_ACCUMULATOR_MIN_64);
-
- seq.litLength = llBase;
- if (llBits > 0)
- seq.litLength += BIT_readBitsFast(&seqState->DStream, llBits/*>0*/);
-
- if (MEM_32bits())
- BIT_reloadDStream(&seqState->DStream);
-
- DEBUGLOG(6, "seq: litL=%u, matchL=%u, offset=%u",
- (U32)seq.litLength, (U32)seq.matchLength, (U32)seq.offset);
-
- if (prefetch == ZSTD_p_prefetch) {
- size_t const pos = seqState->pos + seq.litLength;
- const BYTE* const matchBase = (seq.offset > pos) ? seqState->dictEnd : seqState->prefixStart;
- seq.match = matchBase + pos - seq.offset; /* note : this operation can overflow when seq.offset is really too large, which can only happen when input is corrupted.
- * No consequence though : no memory access will occur, offset is only used for prefetching */
- seqState->pos = pos + seq.matchLength;
- }
-
- /* ANS state update
- * gcc-9.0.0 does 2.5% worse with ZSTD_updateFseStateWithDInfo().
- * clang-9.2.0 does 7% worse with ZSTD_updateFseState().
- * Naturally it seems like ZSTD_updateFseStateWithDInfo() should be the
- * better option, so it is the default for other compilers. But, if you
- * measure that it is worse, please put up a pull request.
- */
- {
-#if !defined(__clang__)
- const int kUseUpdateFseState = 1;
-#else
- const int kUseUpdateFseState = 0;
-#endif
- if (kUseUpdateFseState) {
- ZSTD_updateFseState(&seqState->stateLL, &seqState->DStream); /* <= 9 bits */
- ZSTD_updateFseState(&seqState->stateML, &seqState->DStream); /* <= 9 bits */
- if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream); /* <= 18 bits */
- ZSTD_updateFseState(&seqState->stateOffb, &seqState->DStream); /* <= 8 bits */
- } else {
- ZSTD_updateFseStateWithDInfo(&seqState->stateLL, &seqState->DStream, llDInfo); /* <= 9 bits */
- ZSTD_updateFseStateWithDInfo(&seqState->stateML, &seqState->DStream, mlDInfo); /* <= 9 bits */
- if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream); /* <= 18 bits */
- ZSTD_updateFseStateWithDInfo(&seqState->stateOffb, &seqState->DStream, ofDInfo); /* <= 8 bits */
+ U32 const ll0 = (llDInfo->baseValue == 0);
+ if (LIKELY((ofBits == 0))) {
+ offset = seqState->prevOffset[ll0];
+ seqState->prevOffset[1] = seqState->prevOffset[!ll0];
+ seqState->prevOffset[0] = offset;
+ } else {
+ offset = ofBase + ll0 + BIT_readBitsFast(&seqState->DStream, 1);
+ { size_t temp = (offset==3) ? seqState->prevOffset[0] - 1 : seqState->prevOffset[offset];
+ temp += !temp; /* 0 is not valid; input is corrupted; force offset to 1 */
+ if (offset != 1) seqState->prevOffset[2] = seqState->prevOffset[1];
+ seqState->prevOffset[1] = seqState->prevOffset[0];
+ seqState->prevOffset[0] = offset = temp;
+ } } }
+ seq.offset = offset;
}
+
+ #if defined(__clang__)
+ if (UNLIKELY(mlBits > 0))
+ #else
+ if (mlBits > 0)
+ #endif
+ seq.matchLength += BIT_readBitsFast(&seqState->DStream, mlBits/*>0*/);
+
+ if (MEM_32bits() && (mlBits+llBits >= STREAM_ACCUMULATOR_MIN_32-LONG_OFFSETS_MAX_EXTRA_BITS_32))
+ BIT_reloadDStream(&seqState->DStream);
+ if (MEM_64bits() && UNLIKELY(totalBits >= STREAM_ACCUMULATOR_MIN_64-(LLFSELog+MLFSELog+OffFSELog)))
+ BIT_reloadDStream(&seqState->DStream);
+ /* Ensure there are enough bits to read the rest of data in 64-bit mode. */
+ ZSTD_STATIC_ASSERT(16+LLFSELog+MLFSELog+OffFSELog < STREAM_ACCUMULATOR_MIN_64);
+
+ #if defined(__clang__)
+ if (UNLIKELY(llBits > 0))
+ #else
+ if (llBits > 0)
+ #endif
+ seq.litLength += BIT_readBitsFast(&seqState->DStream, llBits/*>0*/);
+
+ if (MEM_32bits())
+ BIT_reloadDStream(&seqState->DStream);
+
+ DEBUGLOG(6, "seq: litL=%u, matchL=%u, offset=%u",
+ (U32)seq.litLength, (U32)seq.matchLength, (U32)seq.offset);
+
+ ZSTD_updateFseStateWithDInfo(&seqState->stateLL, &seqState->DStream, llNext, llnbBits); /* <= 9 bits */
+ ZSTD_updateFseStateWithDInfo(&seqState->stateML, &seqState->DStream, mlNext, mlnbBits); /* <= 9 bits */
+ if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream); /* <= 18 bits */
+ ZSTD_updateFseStateWithDInfo(&seqState->stateOffb, &seqState->DStream, ofNext, ofnbBits); /* <= 8 bits */
}
return seq;
@@ -1098,9 +1315,11 @@ MEM_STATIC void ZSTD_assertValidSequence(
#endif
#ifndef ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG
+
+
FORCE_INLINE_TEMPLATE size_t
DONT_VECTORIZE
-ZSTD_decompressSequences_body( ZSTD_DCtx* dctx,
+ZSTD_decompressSequences_bodySplitLitBuffer( ZSTD_DCtx* dctx,
void* dst, size_t maxDstSize,
const void* seqStart, size_t seqSize, int nbSeq,
const ZSTD_longOffset_e isLongOffset,
@@ -1112,17 +1331,16 @@ ZSTD_decompressSequences_body( ZSTD_DCtx* dctx,
BYTE* const oend = ostart + maxDstSize;
BYTE* op = ostart;
const BYTE* litPtr = dctx->litPtr;
- const BYTE* const litEnd = litPtr + dctx->litSize;
+ const BYTE* litBufferEnd = dctx->litBufferEnd;
const BYTE* const prefixStart = (const BYTE*) (dctx->prefixStart);
const BYTE* const vBase = (const BYTE*) (dctx->virtualStart);
const BYTE* const dictEnd = (const BYTE*) (dctx->dictEnd);
- DEBUGLOG(5, "ZSTD_decompressSequences_body");
+ DEBUGLOG(5, "ZSTD_decompressSequences_bodySplitLitBuffer");
(void)frame;
/* Regen sequences */
if (nbSeq) {
seqState_t seqState;
- size_t error = 0;
dctx->fseEntropy = 1;
{ U32 i; for (i=0; i<ZSTD_REP_NUM; i++) seqState.prevOffset[i] = dctx->entropy.rep[i]; }
RETURN_ERROR_IF(
@@ -1138,70 +1356,255 @@ ZSTD_decompressSequences_body( ZSTD_DCtx* dctx,
BIT_DStream_endOfBuffer < BIT_DStream_completed &&
BIT_DStream_completed < BIT_DStream_overflow);
+ /* decompress without overrunning litPtr begins */
+ {
+ seq_t sequence = ZSTD_decodeSequence(&seqState, isLongOffset);
+ /* Align the decompression loop to 32 + 16 bytes.
+ *
+ * zstd compiled with gcc-9 on an Intel i9-9900k shows 10% decompression
+ * speed swings based on the alignment of the decompression loop. This
+ * performance swing is caused by parts of the decompression loop falling
+ * out of the DSB. The entire decompression loop should fit in the DSB,
+ * when it can't we get much worse performance. You can measure if you've
+ * hit the good case or the bad case with this perf command for some
+ * compressed file test.zst:
+ *
+ * perf stat -e cycles -e instructions -e idq.all_dsb_cycles_any_uops \
+ * -e idq.all_mite_cycles_any_uops -- ./zstd -tq test.zst
+ *
+ * If you see most cycles served out of the MITE you've hit the bad case.
+ * If you see most cycles served out of the DSB you've hit the good case.
+ * If it is pretty even then you may be in an okay case.
+ *
+ * This issue has been reproduced on the following CPUs:
+ * - Kabylake: Macbook Pro (15-inch, 2019) 2.4 GHz Intel Core i9
+ * Use Instruments->Counters to get DSB/MITE cycles.
+ * I never got performance swings, but I was able to
+ * go from the good case of mostly DSB to half of the
+ * cycles served from MITE.
+ * - Coffeelake: Intel i9-9900k
+ * - Coffeelake: Intel i7-9700k
+ *
+ * I haven't been able to reproduce the instability or DSB misses on any
+ * of the following CPUS:
+ * - Haswell
+ * - Broadwell: Intel(R) Xeon(R) CPU E5-2680 v4 @ 2.40GH
+ * - Skylake
+ *
+ * Alignment is done for each of the three major decompression loops:
+ * - ZSTD_decompressSequences_bodySplitLitBuffer - presplit section of the literal buffer
+ * - ZSTD_decompressSequences_bodySplitLitBuffer - postsplit section of the literal buffer
+ * - ZSTD_decompressSequences_body
+ * Alignment choices are made to minimize large swings on bad cases and influence on performance
+ * from changes external to this code, rather than to overoptimize on the current commit.
+ *
+ * If you are seeing performance stability this script can help test.
+ * It tests on 4 commits in zstd where I saw performance change.
+ *
+ * https://gist.github.com/terrelln/9889fc06a423fd5ca6e99351564473f4
+ */
#if defined(__x86_64__)
- /* Align the decompression loop to 32 + 16 bytes.
- *
- * zstd compiled with gcc-9 on an Intel i9-9900k shows 10% decompression
- * speed swings based on the alignment of the decompression loop. This
- * performance swing is caused by parts of the decompression loop falling
- * out of the DSB. The entire decompression loop should fit in the DSB,
- * when it can't we get much worse performance. You can measure if you've
- * hit the good case or the bad case with this perf command for some
- * compressed file test.zst:
- *
- * perf stat -e cycles -e instructions -e idq.all_dsb_cycles_any_uops \
- * -e idq.all_mite_cycles_any_uops -- ./zstd -tq test.zst
- *
- * If you see most cycles served out of the MITE you've hit the bad case.
- * If you see most cycles served out of the DSB you've hit the good case.
- * If it is pretty even then you may be in an okay case.
- *
- * I've been able to reproduce this issue on the following CPUs:
- * - Kabylake: Macbook Pro (15-inch, 2019) 2.4 GHz Intel Core i9
- * Use Instruments->Counters to get DSB/MITE cycles.
- * I never got performance swings, but I was able to
- * go from the good case of mostly DSB to half of the
- * cycles served from MITE.
- * - Coffeelake: Intel i9-9900k
- *
- * I haven't been able to reproduce the instability or DSB misses on any
- * of the following CPUS:
- * - Haswell
- * - Broadwell: Intel(R) Xeon(R) CPU E5-2680 v4 @ 2.40GH
- * - Skylake
- *
- * If you are seeing performance stability this script can help test.
- * It tests on 4 commits in zstd where I saw performance change.
- *
- * https://gist.github.com/terrelln/9889fc06a423fd5ca6e99351564473f4
- */
- __asm__(".p2align 5");
- __asm__("nop");
- __asm__(".p2align 4");
+ __asm__(".p2align 6");
+# if __GNUC__ >= 7
+ /* good for gcc-7, gcc-9, and gcc-11 */
+ __asm__("nop");
+ __asm__(".p2align 5");
+ __asm__("nop");
+ __asm__(".p2align 4");
+# if __GNUC__ == 8 || __GNUC__ == 10
+ /* good for gcc-8 and gcc-10 */
+ __asm__("nop");
+ __asm__(".p2align 3");
+# endif
+# endif
+#endif
+
+ /* Handle the initial state where litBuffer is currently split between dst and litExtraBuffer */
+ for (; litPtr + sequence.litLength <= dctx->litBufferEnd; ) {
+ size_t const oneSeqSize = ZSTD_execSequenceSplitLitBuffer(op, oend, litPtr + sequence.litLength - WILDCOPY_OVERLENGTH, sequence, &litPtr, litBufferEnd, prefixStart, vBase, dictEnd);
+#if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION) && defined(FUZZING_ASSERT_VALID_SEQUENCE)
+ assert(!ZSTD_isError(oneSeqSize));
+ if (frame) ZSTD_assertValidSequence(dctx, op, oend, sequence, prefixStart, vBase);
+#endif
+ if (UNLIKELY(ZSTD_isError(oneSeqSize)))
+ return oneSeqSize;
+ DEBUGLOG(6, "regenerated sequence size : %u", (U32)oneSeqSize);
+ op += oneSeqSize;
+ if (UNLIKELY(!--nbSeq))
+ break;
+ BIT_reloadDStream(&(seqState.DStream));
+ sequence = ZSTD_decodeSequence(&seqState, isLongOffset);
+ }
+
+ /* If there are more sequences, they will need to read literals from litExtraBuffer; copy over the remainder from dst and update litPtr and litEnd */
+ if (nbSeq > 0) {
+ const size_t leftoverLit = dctx->litBufferEnd - litPtr;
+ if (leftoverLit)
+ {
+ RETURN_ERROR_IF(leftoverLit > (size_t)(oend - op), dstSize_tooSmall, "remaining lit must fit within dstBuffer");
+ ZSTD_safecopyDstBeforeSrc(op, litPtr, leftoverLit);
+ sequence.litLength -= leftoverLit;
+ op += leftoverLit;
+ }
+ litPtr = dctx->litExtraBuffer;
+ litBufferEnd = dctx->litExtraBuffer + ZSTD_LITBUFFEREXTRASIZE;
+ dctx->litBufferLocation = ZSTD_not_in_dst;
+ {
+ size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequence, &litPtr, litBufferEnd, prefixStart, vBase, dictEnd);
+#if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION) && defined(FUZZING_ASSERT_VALID_SEQUENCE)
+ assert(!ZSTD_isError(oneSeqSize));
+ if (frame) ZSTD_assertValidSequence(dctx, op, oend, sequence, prefixStart, vBase);
+#endif
+ if (UNLIKELY(ZSTD_isError(oneSeqSize)))
+ return oneSeqSize;
+ DEBUGLOG(6, "regenerated sequence size : %u", (U32)oneSeqSize);
+ op += oneSeqSize;
+ if (--nbSeq)
+ BIT_reloadDStream(&(seqState.DStream));
+ }
+ }
+ }
+
+ if (nbSeq > 0) /* there is remaining lit from extra buffer */
+ {
+
+#if defined(__x86_64__)
+ __asm__(".p2align 6");
+ __asm__("nop");
+# if __GNUC__ != 7
+ /* worse for gcc-7 better for gcc-8, gcc-9, and gcc-10 and clang */
+ __asm__(".p2align 4");
+ __asm__("nop");
+ __asm__(".p2align 3");
+# elif __GNUC__ >= 11
+ __asm__(".p2align 3");
+# else
+ __asm__(".p2align 5");
+ __asm__("nop");
+ __asm__(".p2align 3");
+# endif
+#endif
+
+ for (; ; ) {
+ seq_t const sequence = ZSTD_decodeSequence(&seqState, isLongOffset);
+ size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequence, &litPtr, litBufferEnd, prefixStart, vBase, dictEnd);
+#if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION) && defined(FUZZING_ASSERT_VALID_SEQUENCE)
+ assert(!ZSTD_isError(oneSeqSize));
+ if (frame) ZSTD_assertValidSequence(dctx, op, oend, sequence, prefixStart, vBase);
+#endif
+ if (UNLIKELY(ZSTD_isError(oneSeqSize)))
+ return oneSeqSize;
+ DEBUGLOG(6, "regenerated sequence size : %u", (U32)oneSeqSize);
+ op += oneSeqSize;
+ if (UNLIKELY(!--nbSeq))
+ break;
+ BIT_reloadDStream(&(seqState.DStream));
+ }
+ }
+
+ /* check if reached exact end */
+ DEBUGLOG(5, "ZSTD_decompressSequences_bodySplitLitBuffer: after decode loop, remaining nbSeq : %i", nbSeq);
+ RETURN_ERROR_IF(nbSeq, corruption_detected, "");
+ RETURN_ERROR_IF(BIT_reloadDStream(&seqState.DStream) < BIT_DStream_completed, corruption_detected, "");
+ /* save reps for next block */
+ { U32 i; for (i=0; i<ZSTD_REP_NUM; i++) dctx->entropy.rep[i] = (U32)(seqState.prevOffset[i]); }
+ }
+
+ /* last literal segment */
+ if (dctx->litBufferLocation == ZSTD_split) /* split hasn't been reached yet, first get dst then copy litExtraBuffer */
+ {
+ size_t const lastLLSize = litBufferEnd - litPtr;
+ RETURN_ERROR_IF(lastLLSize > (size_t)(oend - op), dstSize_tooSmall, "");
+ if (op != NULL) {
+ ZSTD_memmove(op, litPtr, lastLLSize);
+ op += lastLLSize;
+ }
+ litPtr = dctx->litExtraBuffer;
+ litBufferEnd = dctx->litExtraBuffer + ZSTD_LITBUFFEREXTRASIZE;
+ dctx->litBufferLocation = ZSTD_not_in_dst;
+ }
+ { size_t const lastLLSize = litBufferEnd - litPtr;
+ RETURN_ERROR_IF(lastLLSize > (size_t)(oend-op), dstSize_tooSmall, "");
+ if (op != NULL) {
+ ZSTD_memcpy(op, litPtr, lastLLSize);
+ op += lastLLSize;
+ }
+ }
+
+ return op-ostart;
+}
+
+FORCE_INLINE_TEMPLATE size_t
+DONT_VECTORIZE
+ZSTD_decompressSequences_body(ZSTD_DCtx* dctx,
+ void* dst, size_t maxDstSize,
+ const void* seqStart, size_t seqSize, int nbSeq,
+ const ZSTD_longOffset_e isLongOffset,
+ const int frame)
+{
+ const BYTE* ip = (const BYTE*)seqStart;
+ const BYTE* const iend = ip + seqSize;
+ BYTE* const ostart = (BYTE*)dst;
+ BYTE* const oend = dctx->litBufferLocation == ZSTD_not_in_dst ? ostart + maxDstSize : dctx->litBuffer;
+ BYTE* op = ostart;
+ const BYTE* litPtr = dctx->litPtr;
+ const BYTE* const litEnd = litPtr + dctx->litSize;
+ const BYTE* const prefixStart = (const BYTE*)(dctx->prefixStart);
+ const BYTE* const vBase = (const BYTE*)(dctx->virtualStart);
+ const BYTE* const dictEnd = (const BYTE*)(dctx->dictEnd);
+ DEBUGLOG(5, "ZSTD_decompressSequences_body");
+ (void)frame;
+
+ /* Regen sequences */
+ if (nbSeq) {
+ seqState_t seqState;
+ dctx->fseEntropy = 1;
+ { U32 i; for (i = 0; i < ZSTD_REP_NUM; i++) seqState.prevOffset[i] = dctx->entropy.rep[i]; }
+ RETURN_ERROR_IF(
+ ERR_isError(BIT_initDStream(&seqState.DStream, ip, iend - ip)),
+ corruption_detected, "");
+ ZSTD_initFseState(&seqState.stateLL, &seqState.DStream, dctx->LLTptr);
+ ZSTD_initFseState(&seqState.stateOffb, &seqState.DStream, dctx->OFTptr);
+ ZSTD_initFseState(&seqState.stateML, &seqState.DStream, dctx->MLTptr);
+ assert(dst != NULL);
+
+ ZSTD_STATIC_ASSERT(
+ BIT_DStream_unfinished < BIT_DStream_completed &&
+ BIT_DStream_endOfBuffer < BIT_DStream_completed &&
+ BIT_DStream_completed < BIT_DStream_overflow);
+
+#if defined(__x86_64__)
+ __asm__(".p2align 6");
+ __asm__("nop");
+# if __GNUC__ >= 7
+ __asm__(".p2align 5");
+ __asm__("nop");
+ __asm__(".p2align 3");
+# else
+ __asm__(".p2align 4");
+ __asm__("nop");
+ __asm__(".p2align 3");
+# endif
#endif
+
for ( ; ; ) {
- seq_t const sequence = ZSTD_decodeSequence(&seqState, isLongOffset, ZSTD_p_noPrefetch);
+ seq_t const sequence = ZSTD_decodeSequence(&seqState, isLongOffset);
size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequence, &litPtr, litEnd, prefixStart, vBase, dictEnd);
#if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION) && defined(FUZZING_ASSERT_VALID_SEQUENCE)
assert(!ZSTD_isError(oneSeqSize));
if (frame) ZSTD_assertValidSequence(dctx, op, oend, sequence, prefixStart, vBase);
#endif
+ if (UNLIKELY(ZSTD_isError(oneSeqSize)))
+ return oneSeqSize;
DEBUGLOG(6, "regenerated sequence size : %u", (U32)oneSeqSize);
- BIT_reloadDStream(&(seqState.DStream));
op += oneSeqSize;
- /* gcc and clang both don't like early returns in this loop.
- * Instead break and check for an error at the end of the loop.
- */
- if (UNLIKELY(ZSTD_isError(oneSeqSize))) {
- error = oneSeqSize;
+ if (UNLIKELY(!--nbSeq))
break;
- }
- if (UNLIKELY(!--nbSeq)) break;
+ BIT_reloadDStream(&(seqState.DStream));
}
/* check if reached exact end */
DEBUGLOG(5, "ZSTD_decompressSequences_body: after decode loop, remaining nbSeq : %i", nbSeq);
- if (ZSTD_isError(error)) return error;
RETURN_ERROR_IF(nbSeq, corruption_detected, "");
RETURN_ERROR_IF(BIT_reloadDStream(&seqState.DStream) < BIT_DStream_completed, corruption_detected, "");
/* save reps for next block */
@@ -1229,9 +1632,37 @@ ZSTD_decompressSequences_default(ZSTD_DCtx* dctx,
{
return ZSTD_decompressSequences_body(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset, frame);
}
+
+static size_t
+ZSTD_decompressSequencesSplitLitBuffer_default(ZSTD_DCtx* dctx,
+ void* dst, size_t maxDstSize,
+ const void* seqStart, size_t seqSize, int nbSeq,
+ const ZSTD_longOffset_e isLongOffset,
+ const int frame)
+{
+ return ZSTD_decompressSequences_bodySplitLitBuffer(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset, frame);
+}
#endif /* ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG */
#ifndef ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT
+
+FORCE_INLINE_TEMPLATE size_t
+ZSTD_prefetchMatch(size_t prefetchPos, seq_t const sequence,
+ const BYTE* const prefixStart, const BYTE* const dictEnd)
+{
+ prefetchPos += sequence.litLength;
+ { const BYTE* const matchBase = (sequence.offset > prefetchPos) ? dictEnd : prefixStart;
+ const BYTE* const match = matchBase + prefetchPos - sequence.offset; /* note : this operation can overflow when seq.offset is really too large, which can only happen when input is corrupted.
+ * No consequence though : memory address is only used for prefetching, not for dereferencing */
+ PREFETCH_L1(match); PREFETCH_L1(match+CACHELINE_SIZE); /* note : it's safe to invoke PREFETCH() on any memory address, including invalid ones */
+ }
+ return prefetchPos + sequence.matchLength;
+}
+
+/* This decoding function employs prefetching
+ * to reduce latency impact of cache misses.
+ * It's generally employed when block contains a significant portion of long-distance matches
+ * or when coupled with a "cold" dictionary */
FORCE_INLINE_TEMPLATE size_t
ZSTD_decompressSequencesLong_body(
ZSTD_DCtx* dctx,
@@ -1243,10 +1674,10 @@ ZSTD_decompressSequencesLong_body(
const BYTE* ip = (const BYTE*)seqStart;
const BYTE* const iend = ip + seqSize;
BYTE* const ostart = (BYTE*)dst;
- BYTE* const oend = ostart + maxDstSize;
+ BYTE* const oend = dctx->litBufferLocation == ZSTD_in_dst ? dctx->litBuffer : ostart + maxDstSize;
BYTE* op = ostart;
const BYTE* litPtr = dctx->litPtr;
- const BYTE* const litEnd = litPtr + dctx->litSize;
+ const BYTE* litBufferEnd = dctx->litBufferEnd;
const BYTE* const prefixStart = (const BYTE*) (dctx->prefixStart);
const BYTE* const dictStart = (const BYTE*) (dctx->virtualStart);
const BYTE* const dictEnd = (const BYTE*) (dctx->dictEnd);
@@ -1254,18 +1685,17 @@ ZSTD_decompressSequencesLong_body(
/* Regen sequences */
if (nbSeq) {
-#define STORED_SEQS 4
+#define STORED_SEQS 8
#define STORED_SEQS_MASK (STORED_SEQS-1)
-#define ADVANCED_SEQS 4
+#define ADVANCED_SEQS STORED_SEQS
seq_t sequences[STORED_SEQS];
int const seqAdvance = MIN(nbSeq, ADVANCED_SEQS);
seqState_t seqState;
int seqNb;
+ size_t prefetchPos = (size_t)(op-prefixStart); /* track position relative to prefixStart */
+
dctx->fseEntropy = 1;
{ int i; for (i=0; i<ZSTD_REP_NUM; i++) seqState.prevOffset[i] = dctx->entropy.rep[i]; }
- seqState.prefixStart = prefixStart;
- seqState.pos = (size_t)(op-prefixStart);
- seqState.dictEnd = dictEnd;
assert(dst != NULL);
assert(iend >= ip);
RETURN_ERROR_IF(
@@ -1277,36 +1707,100 @@ ZSTD_decompressSequencesLong_body(
/* prepare in advance */
for (seqNb=0; (BIT_reloadDStream(&seqState.DStream) <= BIT_DStream_completed) && (seqNb<seqAdvance); seqNb++) {
- sequences[seqNb] = ZSTD_decodeSequence(&seqState, isLongOffset, ZSTD_p_prefetch);
- PREFETCH_L1(sequences[seqNb].match); PREFETCH_L1(sequences[seqNb].match + sequences[seqNb].matchLength - 1); /* note : it's safe to invoke PREFETCH() on any memory address, including invalid ones */
+ seq_t const sequence = ZSTD_decodeSequence(&seqState, isLongOffset);
+ prefetchPos = ZSTD_prefetchMatch(prefetchPos, sequence, prefixStart, dictEnd);
+ sequences[seqNb] = sequence;
}
RETURN_ERROR_IF(seqNb<seqAdvance, corruption_detected, "");
- /* decode and decompress */
- for ( ; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && (seqNb<nbSeq) ; seqNb++) {
- seq_t const sequence = ZSTD_decodeSequence(&seqState, isLongOffset, ZSTD_p_prefetch);
- size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequences[(seqNb-ADVANCED_SEQS) & STORED_SEQS_MASK], &litPtr, litEnd, prefixStart, dictStart, dictEnd);
+ /* decompress without stomping litBuffer */
+ for (; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && (seqNb < nbSeq); seqNb++) {
+ seq_t sequence = ZSTD_decodeSequence(&seqState, isLongOffset);
+ size_t oneSeqSize;
+
+ if (dctx->litBufferLocation == ZSTD_split && litPtr + sequences[(seqNb - ADVANCED_SEQS) & STORED_SEQS_MASK].litLength > dctx->litBufferEnd)
+ {
+ /* lit buffer is reaching split point, empty out the first buffer and transition to litExtraBuffer */
+ const size_t leftoverLit = dctx->litBufferEnd - litPtr;
+ if (leftoverLit)
+ {
+ RETURN_ERROR_IF(leftoverLit > (size_t)(oend - op), dstSize_tooSmall, "remaining lit must fit within dstBuffer");
+ ZSTD_safecopyDstBeforeSrc(op, litPtr, leftoverLit);
+ sequences[(seqNb - ADVANCED_SEQS) & STORED_SEQS_MASK].litLength -= leftoverLit;
+ op += leftoverLit;
+ }
+ litPtr = dctx->litExtraBuffer;
+ litBufferEnd = dctx->litExtraBuffer + ZSTD_LITBUFFEREXTRASIZE;
+ dctx->litBufferLocation = ZSTD_not_in_dst;
+ oneSeqSize = ZSTD_execSequence(op, oend, sequences[(seqNb - ADVANCED_SEQS) & STORED_SEQS_MASK], &litPtr, litBufferEnd, prefixStart, dictStart, dictEnd);
#if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION) && defined(FUZZING_ASSERT_VALID_SEQUENCE)
- assert(!ZSTD_isError(oneSeqSize));
- if (frame) ZSTD_assertValidSequence(dctx, op, oend, sequences[(seqNb-ADVANCED_SEQS) & STORED_SEQS_MASK], prefixStart, dictStart);
+ assert(!ZSTD_isError(oneSeqSize));
+ if (frame) ZSTD_assertValidSequence(dctx, op, oend, sequences[(seqNb - ADVANCED_SEQS) & STORED_SEQS_MASK], prefixStart, dictStart);
#endif
- if (ZSTD_isError(oneSeqSize)) return oneSeqSize;
- PREFETCH_L1(sequence.match); PREFETCH_L1(sequence.match + sequence.matchLength - 1); /* note : it's safe to invoke PREFETCH() on any memory address, including invalid ones */
- sequences[seqNb & STORED_SEQS_MASK] = sequence;
- op += oneSeqSize;
+ if (ZSTD_isError(oneSeqSize)) return oneSeqSize;
+
+ prefetchPos = ZSTD_prefetchMatch(prefetchPos, sequence, prefixStart, dictEnd);
+ sequences[seqNb & STORED_SEQS_MASK] = sequence;
+ op += oneSeqSize;
+ }
+ else
+ {
+ /* lit buffer is either wholly contained in first or second split, or not split at all*/
+ oneSeqSize = dctx->litBufferLocation == ZSTD_split ?
+ ZSTD_execSequenceSplitLitBuffer(op, oend, litPtr + sequences[(seqNb - ADVANCED_SEQS) & STORED_SEQS_MASK].litLength - WILDCOPY_OVERLENGTH, sequences[(seqNb - ADVANCED_SEQS) & STORED_SEQS_MASK], &litPtr, litBufferEnd, prefixStart, dictStart, dictEnd) :
+ ZSTD_execSequence(op, oend, sequences[(seqNb - ADVANCED_SEQS) & STORED_SEQS_MASK], &litPtr, litBufferEnd, prefixStart, dictStart, dictEnd);
+#if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION) && defined(FUZZING_ASSERT_VALID_SEQUENCE)
+ assert(!ZSTD_isError(oneSeqSize));
+ if (frame) ZSTD_assertValidSequence(dctx, op, oend, sequences[(seqNb - ADVANCED_SEQS) & STORED_SEQS_MASK], prefixStart, dictStart);
+#endif
+ if (ZSTD_isError(oneSeqSize)) return oneSeqSize;
+
+ prefetchPos = ZSTD_prefetchMatch(prefetchPos, sequence, prefixStart, dictEnd);
+ sequences[seqNb & STORED_SEQS_MASK] = sequence;
+ op += oneSeqSize;
+ }
}
RETURN_ERROR_IF(seqNb<nbSeq, corruption_detected, "");
/* finish queue */
seqNb -= seqAdvance;
for ( ; seqNb<nbSeq ; seqNb++) {
- size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequences[seqNb&STORED_SEQS_MASK], &litPtr, litEnd, prefixStart, dictStart, dictEnd);
+ seq_t *sequence = &(sequences[seqNb&STORED_SEQS_MASK]);
+ if (dctx->litBufferLocation == ZSTD_split && litPtr + sequence->litLength > dctx->litBufferEnd)
+ {
+ const size_t leftoverLit = dctx->litBufferEnd - litPtr;
+ if (leftoverLit)
+ {
+ RETURN_ERROR_IF(leftoverLit > (size_t)(oend - op), dstSize_tooSmall, "remaining lit must fit within dstBuffer");
+ ZSTD_safecopyDstBeforeSrc(op, litPtr, leftoverLit);
+ sequence->litLength -= leftoverLit;
+ op += leftoverLit;
+ }
+ litPtr = dctx->litExtraBuffer;
+ litBufferEnd = dctx->litExtraBuffer + ZSTD_LITBUFFEREXTRASIZE;
+ dctx->litBufferLocation = ZSTD_not_in_dst;
+ {
+ size_t const oneSeqSize = ZSTD_execSequence(op, oend, *sequence, &litPtr, litBufferEnd, prefixStart, dictStart, dictEnd);
#if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION) && defined(FUZZING_ASSERT_VALID_SEQUENCE)
- assert(!ZSTD_isError(oneSeqSize));
- if (frame) ZSTD_assertValidSequence(dctx, op, oend, sequences[seqNb&STORED_SEQS_MASK], prefixStart, dictStart);
+ assert(!ZSTD_isError(oneSeqSize));
+ if (frame) ZSTD_assertValidSequence(dctx, op, oend, sequences[seqNb&STORED_SEQS_MASK], prefixStart, dictStart);
#endif
- if (ZSTD_isError(oneSeqSize)) return oneSeqSize;
- op += oneSeqSize;
+ if (ZSTD_isError(oneSeqSize)) return oneSeqSize;
+ op += oneSeqSize;
+ }
+ }
+ else
+ {
+ size_t const oneSeqSize = dctx->litBufferLocation == ZSTD_split ?
+ ZSTD_execSequenceSplitLitBuffer(op, oend, litPtr + sequence->litLength - WILDCOPY_OVERLENGTH, *sequence, &litPtr, litBufferEnd, prefixStart, dictStart, dictEnd) :
+ ZSTD_execSequence(op, oend, *sequence, &litPtr, litBufferEnd, prefixStart, dictStart, dictEnd);
+#if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION) && defined(FUZZING_ASSERT_VALID_SEQUENCE)
+ assert(!ZSTD_isError(oneSeqSize));
+ if (frame) ZSTD_assertValidSequence(dctx, op, oend, sequences[seqNb&STORED_SEQS_MASK], prefixStart, dictStart);
+#endif
+ if (ZSTD_isError(oneSeqSize)) return oneSeqSize;
+ op += oneSeqSize;
+ }
}
/* save reps for next block */
@@ -1314,10 +1808,21 @@ ZSTD_decompressSequencesLong_body(
}
/* last literal segment */
- { size_t const lastLLSize = litEnd - litPtr;
+ if (dctx->litBufferLocation == ZSTD_split) /* first deplete literal buffer in dst, then copy litExtraBuffer */
+ {
+ size_t const lastLLSize = litBufferEnd - litPtr;
+ RETURN_ERROR_IF(lastLLSize > (size_t)(oend - op), dstSize_tooSmall, "");
+ if (op != NULL) {
+ ZSTD_memmove(op, litPtr, lastLLSize);
+ op += lastLLSize;
+ }
+ litPtr = dctx->litExtraBuffer;
+ litBufferEnd = dctx->litExtraBuffer + ZSTD_LITBUFFEREXTRASIZE;
+ }
+ { size_t const lastLLSize = litBufferEnd - litPtr;
RETURN_ERROR_IF(lastLLSize > (size_t)(oend-op), dstSize_tooSmall, "");
if (op != NULL) {
- ZSTD_memcpy(op, litPtr, lastLLSize);
+ ZSTD_memmove(op, litPtr, lastLLSize);
op += lastLLSize;
}
}
@@ -1341,7 +1846,7 @@ ZSTD_decompressSequencesLong_default(ZSTD_DCtx* dctx,
#if DYNAMIC_BMI2
#ifndef ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG
-static TARGET_ATTRIBUTE("bmi2") size_t
+static BMI2_TARGET_ATTRIBUTE size_t
DONT_VECTORIZE
ZSTD_decompressSequences_bmi2(ZSTD_DCtx* dctx,
void* dst, size_t maxDstSize,
@@ -1351,10 +1856,20 @@ ZSTD_decompressSequences_bmi2(ZSTD_DCtx* dctx,
{
return ZSTD_decompressSequences_body(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset, frame);
}
+static BMI2_TARGET_ATTRIBUTE size_t
+DONT_VECTORIZE
+ZSTD_decompressSequencesSplitLitBuffer_bmi2(ZSTD_DCtx* dctx,
+ void* dst, size_t maxDstSize,
+ const void* seqStart, size_t seqSize, int nbSeq,
+ const ZSTD_longOffset_e isLongOffset,
+ const int frame)
+{
+ return ZSTD_decompressSequences_bodySplitLitBuffer(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset, frame);
+}
#endif /* ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG */
#ifndef ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT
-static TARGET_ATTRIBUTE("bmi2") size_t
+static BMI2_TARGET_ATTRIBUTE size_t
ZSTD_decompressSequencesLong_bmi2(ZSTD_DCtx* dctx,
void* dst, size_t maxDstSize,
const void* seqStart, size_t seqSize, int nbSeq,
@@ -1383,11 +1898,25 @@ ZSTD_decompressSequences(ZSTD_DCtx* dctx, void* dst, size_t maxDstSize,
{
DEBUGLOG(5, "ZSTD_decompressSequences");
#if DYNAMIC_BMI2
- if (dctx->bmi2) {
+ if (ZSTD_DCtx_get_bmi2(dctx)) {
return ZSTD_decompressSequences_bmi2(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset, frame);
}
#endif
- return ZSTD_decompressSequences_default(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset, frame);
+ return ZSTD_decompressSequences_default(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset, frame);
+}
+static size_t
+ZSTD_decompressSequencesSplitLitBuffer(ZSTD_DCtx* dctx, void* dst, size_t maxDstSize,
+ const void* seqStart, size_t seqSize, int nbSeq,
+ const ZSTD_longOffset_e isLongOffset,
+ const int frame)
+{
+ DEBUGLOG(5, "ZSTD_decompressSequencesSplitLitBuffer");
+#if DYNAMIC_BMI2
+ if (ZSTD_DCtx_get_bmi2(dctx)) {
+ return ZSTD_decompressSequencesSplitLitBuffer_bmi2(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset, frame);
+ }
+#endif
+ return ZSTD_decompressSequencesSplitLitBuffer_default(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset, frame);
}
#endif /* ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG */
@@ -1407,7 +1936,7 @@ ZSTD_decompressSequencesLong(ZSTD_DCtx* dctx,
{
DEBUGLOG(5, "ZSTD_decompressSequencesLong");
#if DYNAMIC_BMI2
- if (dctx->bmi2) {
+ if (ZSTD_DCtx_get_bmi2(dctx)) {
return ZSTD_decompressSequencesLong_bmi2(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset, frame);
}
#endif
@@ -1448,7 +1977,7 @@ ZSTD_getLongOffsetsShare(const ZSTD_seqSymbol* offTable)
size_t
ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx,
void* dst, size_t dstCapacity,
- const void* src, size_t srcSize, const int frame)
+ const void* src, size_t srcSize, const int frame, const streaming_operation streaming)
{ /* blockType == blockCompressed */
const BYTE* ip = (const BYTE*)src;
/* isLongOffset must be true if there are long offsets.
@@ -1463,7 +1992,7 @@ ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx,
RETURN_ERROR_IF(srcSize >= ZSTD_BLOCKSIZE_MAX, srcSize_wrong, "");
/* Decode literals section */
- { size_t const litCSize = ZSTD_decodeLiteralsBlock(dctx, src, srcSize);
+ { size_t const litCSize = ZSTD_decodeLiteralsBlock(dctx, src, srcSize, dst, dstCapacity, streaming);
DEBUGLOG(5, "ZSTD_decodeLiteralsBlock : %u", (U32)litCSize);
if (ZSTD_isError(litCSize)) return litCSize;
ip += litCSize;
@@ -1511,7 +2040,10 @@ ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx,
#ifndef ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG
/* else */
- return ZSTD_decompressSequences(dctx, dst, dstCapacity, ip, srcSize, nbSeq, isLongOffset, frame);
+ if (dctx->litBufferLocation == ZSTD_split)
+ return ZSTD_decompressSequencesSplitLitBuffer(dctx, dst, dstCapacity, ip, srcSize, nbSeq, isLongOffset, frame);
+ else
+ return ZSTD_decompressSequences(dctx, dst, dstCapacity, ip, srcSize, nbSeq, isLongOffset, frame);
#endif
}
}
@@ -1534,7 +2066,7 @@ size_t ZSTD_decompressBlock(ZSTD_DCtx* dctx,
{
size_t dSize;
ZSTD_checkContinuity(dctx, dst, dstCapacity);
- dSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize, /* frame */ 0);
+ dSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize, /* frame */ 0, not_streaming);
dctx->previousDstEnd = (char*)dst + dSize;
return dSize;
}
diff --git a/lib/zstd/decompress/zstd_decompress_block.h b/lib/zstd/decompress/zstd_decompress_block.h
index e7f5f6689459..3d2d57a5d25a 100644
--- a/lib/zstd/decompress/zstd_decompress_block.h
+++ b/lib/zstd/decompress/zstd_decompress_block.h
@@ -33,6 +33,12 @@
*/
+ /* Streaming state is used to inform allocation of the literal buffer */
+typedef enum {
+ not_streaming = 0,
+ is_streaming = 1
+} streaming_operation;
+
/* ZSTD_decompressBlock_internal() :
* decompress block, starting at `src`,
* into destination buffer `dst`.
@@ -41,7 +47,7 @@
*/
size_t ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx,
void* dst, size_t dstCapacity,
- const void* src, size_t srcSize, const int frame);
+ const void* src, size_t srcSize, const int frame, const streaming_operation streaming);
/* ZSTD_buildFSETable() :
* generate FSE decoding table for one symbol (ll, ml or off)
@@ -54,7 +60,7 @@ size_t ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx,
*/
void ZSTD_buildFSETable(ZSTD_seqSymbol* dt,
const short* normalizedCounter, unsigned maxSymbolValue,
- const U32* baseValue, const U32* nbAdditionalBits,
+ const U32* baseValue, const U8* nbAdditionalBits,
unsigned tableLog, void* wksp, size_t wkspSize,
int bmi2);
diff --git a/lib/zstd/decompress/zstd_decompress_internal.h b/lib/zstd/decompress/zstd_decompress_internal.h
index 4b9052f68755..98102edb6a83 100644
--- a/lib/zstd/decompress/zstd_decompress_internal.h
+++ b/lib/zstd/decompress/zstd_decompress_internal.h
@@ -20,7 +20,7 @@
* Dependencies
*********************************************************/
#include "../common/mem.h" /* BYTE, U16, U32 */
-#include "../common/zstd_internal.h" /* ZSTD_seqSymbol */
+#include "../common/zstd_internal.h" /* constants : MaxLL, MaxML, MaxOff, LLFSELog, etc. */
@@ -40,7 +40,7 @@ static UNUSED_ATTR const U32 OF_base[MaxOff+1] = {
0xFFFD, 0x1FFFD, 0x3FFFD, 0x7FFFD, 0xFFFFD, 0x1FFFFD, 0x3FFFFD, 0x7FFFFD,
0xFFFFFD, 0x1FFFFFD, 0x3FFFFFD, 0x7FFFFFD, 0xFFFFFFD, 0x1FFFFFFD, 0x3FFFFFFD, 0x7FFFFFFD };
-static UNUSED_ATTR const U32 OF_bits[MaxOff+1] = {
+static UNUSED_ATTR const U8 OF_bits[MaxOff+1] = {
0, 1, 2, 3, 4, 5, 6, 7,
8, 9, 10, 11, 12, 13, 14, 15,
16, 17, 18, 19, 20, 21, 22, 23,
@@ -106,6 +106,22 @@ typedef struct {
size_t ddictPtrCount;
} ZSTD_DDictHashSet;
+#ifndef ZSTD_DECODER_INTERNAL_BUFFER
+# define ZSTD_DECODER_INTERNAL_BUFFER (1 << 16)
+#endif
+
+#define ZSTD_LBMIN 64
+#define ZSTD_LBMAX (128 << 10)
+
+/* extra buffer, compensates when dst is not large enough to store litBuffer */
+#define ZSTD_LITBUFFEREXTRASIZE BOUNDED(ZSTD_LBMIN, ZSTD_DECODER_INTERNAL_BUFFER, ZSTD_LBMAX)
+
+typedef enum {
+ ZSTD_not_in_dst = 0, /* Stored entirely within litExtraBuffer */
+ ZSTD_in_dst = 1, /* Stored entirely within dst (in memory after current output write) */
+ ZSTD_split = 2 /* Split between litExtraBuffer and dst */
+} ZSTD_litLocation_e;
+
struct ZSTD_DCtx_s
{
const ZSTD_seqSymbol* LLTptr;
@@ -136,7 +152,9 @@ struct ZSTD_DCtx_s
size_t litSize;
size_t rleSize;
size_t staticSize;
+#if DYNAMIC_BMI2 != 0
int bmi2; /* == 1 if the CPU supports BMI2 and 0 otherwise. CPU support is determined dynamically once per context lifetime. */
+#endif
/* dictionary */
ZSTD_DDict* ddictLocal;
@@ -158,16 +176,16 @@ struct ZSTD_DCtx_s
size_t outStart;
size_t outEnd;
size_t lhSize;
- void* legacyContext;
- U32 previousLegacyVersion;
- U32 legacyVersion;
U32 hostageByte;
int noForwardProgress;
ZSTD_bufferMode_e outBufferMode;
ZSTD_outBuffer expectedOutBuffer;
/* workspace */
- BYTE litBuffer[ZSTD_BLOCKSIZE_MAX + WILDCOPY_OVERLENGTH];
+ BYTE* litBuffer;
+ const BYTE* litBufferEnd;
+ ZSTD_litLocation_e litBufferLocation;
+ BYTE litExtraBuffer[ZSTD_LITBUFFEREXTRASIZE + WILDCOPY_OVERLENGTH]; /* literal buffer can be split between storage within dst and within this scratch buffer */
BYTE headerBuffer[ZSTD_FRAMEHEADERSIZE_MAX];
size_t oversizedDuration;
@@ -180,6 +198,14 @@ struct ZSTD_DCtx_s
/* Tracing */
}; /* typedef'd to ZSTD_DCtx within "zstd.h" */
+MEM_STATIC int ZSTD_DCtx_get_bmi2(const struct ZSTD_DCtx_s *dctx) {
+#if DYNAMIC_BMI2 != 0
+ return dctx->bmi2;
+#else
+ (void)dctx;
+ return 0;
+#endif
+}
/*-*******************************************************
* Shared internal functions
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-23 17:55:15 +0000