Update deps
This commit is contained in:
314
vendor/github.com/DataDog/zstd/huf_decompress.c
generated
vendored
314
vendor/github.com/DataDog/zstd/huf_decompress.c
generated
vendored
@@ -35,6 +35,12 @@
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* Macros
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****************************************************************/
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#ifdef HUF_DISABLE_FAST_DECODE
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# define HUF_ENABLE_FAST_DECODE 0
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#else
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# define HUF_ENABLE_FAST_DECODE 1
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#endif
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/* These two optional macros force the use one way or another of the two
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* Huffman decompression implementations. You can't force in both directions
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* at the same time.
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@@ -159,17 +165,18 @@ static size_t HUF_initFastDStream(BYTE const* ip) {
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* op [in/out] - The output pointers, must be updated to reflect what is written.
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* bits [in/out] - The bitstream containers, must be updated to reflect the current state.
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* dt [in] - The decoding table.
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* ilimit [in] - The input limit, stop when any input pointer is below ilimit.
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* ilowest [in] - The beginning of the valid range of the input. Decoders may read
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* down to this pointer. It may be below iend[0].
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* oend [in] - The end of the output stream. op[3] must not cross oend.
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* iend [in] - The end of each input stream. ip[i] may cross iend[i],
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* as long as it is above ilimit, but that indicates corruption.
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* as long as it is above ilowest, but that indicates corruption.
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*/
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typedef struct {
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BYTE const* ip[4];
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BYTE* op[4];
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U64 bits[4];
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void const* dt;
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BYTE const* ilimit;
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BYTE const* ilowest;
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BYTE* oend;
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BYTE const* iend[4];
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} HUF_DecompressFastArgs;
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@@ -187,9 +194,9 @@ static size_t HUF_DecompressFastArgs_init(HUF_DecompressFastArgs* args, void* ds
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void const* dt = DTable + 1;
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U32 const dtLog = HUF_getDTableDesc(DTable).tableLog;
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const BYTE* const ilimit = (const BYTE*)src + 6 + 8;
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const BYTE* const istart = (const BYTE*)src;
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BYTE* const oend = (BYTE*)dst + dstSize;
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BYTE* const oend = ZSTD_maybeNullPtrAdd((BYTE*)dst, dstSize);
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/* The fast decoding loop assumes 64-bit little-endian.
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* This condition is false on x32.
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@@ -197,6 +204,11 @@ static size_t HUF_DecompressFastArgs_init(HUF_DecompressFastArgs* args, void* ds
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if (!MEM_isLittleEndian() || MEM_32bits())
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return 0;
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/* Avoid nullptr addition */
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if (dstSize == 0)
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return 0;
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assert(dst != NULL);
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/* strict minimum : jump table + 1 byte per stream */
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if (srcSize < 10)
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return ERROR(corruption_detected);
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@@ -210,7 +222,6 @@ static size_t HUF_DecompressFastArgs_init(HUF_DecompressFastArgs* args, void* ds
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/* Read the jump table. */
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{
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const BYTE* const istart = (const BYTE*)src;
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size_t const length1 = MEM_readLE16(istart);
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size_t const length2 = MEM_readLE16(istart+2);
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size_t const length3 = MEM_readLE16(istart+4);
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@@ -222,10 +233,8 @@ static size_t HUF_DecompressFastArgs_init(HUF_DecompressFastArgs* args, void* ds
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/* HUF_initFastDStream() requires this, and this small of an input
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* won't benefit from the ASM loop anyways.
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* length1 must be >= 16 so that ip[0] >= ilimit before the loop
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* starts.
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*/
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if (length1 < 16 || length2 < 8 || length3 < 8 || length4 < 8)
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if (length1 < 8 || length2 < 8 || length3 < 8 || length4 < 8)
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return 0;
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if (length4 > srcSize) return ERROR(corruption_detected); /* overflow */
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}
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@@ -257,11 +266,12 @@ static size_t HUF_DecompressFastArgs_init(HUF_DecompressFastArgs* args, void* ds
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args->bits[2] = HUF_initFastDStream(args->ip[2]);
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args->bits[3] = HUF_initFastDStream(args->ip[3]);
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/* If ip[] >= ilimit, it is guaranteed to be safe to
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* reload bits[]. It may be beyond its section, but is
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* guaranteed to be valid (>= istart).
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*/
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args->ilimit = ilimit;
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/* The decoders must be sure to never read beyond ilowest.
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* This is lower than iend[0], but allowing decoders to read
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* down to ilowest can allow an extra iteration or two in the
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* fast loop.
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*/
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args->ilowest = istart;
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args->oend = oend;
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args->dt = dt;
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@@ -286,13 +296,31 @@ static size_t HUF_initRemainingDStream(BIT_DStream_t* bit, HUF_DecompressFastArg
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assert(sizeof(size_t) == 8);
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bit->bitContainer = MEM_readLEST(args->ip[stream]);
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bit->bitsConsumed = ZSTD_countTrailingZeros64(args->bits[stream]);
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bit->start = (const char*)args->iend[0];
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bit->start = (const char*)args->ilowest;
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bit->limitPtr = bit->start + sizeof(size_t);
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bit->ptr = (const char*)args->ip[stream];
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return 0;
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}
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/* Calls X(N) for each stream 0, 1, 2, 3. */
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#define HUF_4X_FOR_EACH_STREAM(X) \
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do { \
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X(0); \
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X(1); \
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X(2); \
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X(3); \
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} while (0)
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/* Calls X(N, var) for each stream 0, 1, 2, 3. */
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#define HUF_4X_FOR_EACH_STREAM_WITH_VAR(X, var) \
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do { \
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X(0, (var)); \
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X(1, (var)); \
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X(2, (var)); \
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X(3, (var)); \
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} while (0)
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#ifndef HUF_FORCE_DECOMPRESS_X2
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@@ -501,15 +529,19 @@ HUF_decodeSymbolX1(BIT_DStream_t* Dstream, const HUF_DEltX1* dt, const U32 dtLog
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}
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#define HUF_DECODE_SYMBOLX1_0(ptr, DStreamPtr) \
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*ptr++ = HUF_decodeSymbolX1(DStreamPtr, dt, dtLog)
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do { *ptr++ = HUF_decodeSymbolX1(DStreamPtr, dt, dtLog); } while (0)
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#define HUF_DECODE_SYMBOLX1_1(ptr, DStreamPtr) \
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if (MEM_64bits() || (HUF_TABLELOG_MAX<=12)) \
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HUF_DECODE_SYMBOLX1_0(ptr, DStreamPtr)
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#define HUF_DECODE_SYMBOLX1_1(ptr, DStreamPtr) \
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do { \
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if (MEM_64bits() || (HUF_TABLELOG_MAX<=12)) \
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HUF_DECODE_SYMBOLX1_0(ptr, DStreamPtr); \
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} while (0)
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#define HUF_DECODE_SYMBOLX1_2(ptr, DStreamPtr) \
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if (MEM_64bits()) \
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HUF_DECODE_SYMBOLX1_0(ptr, DStreamPtr)
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#define HUF_DECODE_SYMBOLX1_2(ptr, DStreamPtr) \
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do { \
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if (MEM_64bits()) \
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HUF_DECODE_SYMBOLX1_0(ptr, DStreamPtr); \
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} while (0)
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HINT_INLINE size_t
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HUF_decodeStreamX1(BYTE* p, BIT_DStream_t* const bitDPtr, BYTE* const pEnd, const HUF_DEltX1* const dt, const U32 dtLog)
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@@ -547,7 +579,7 @@ HUF_decompress1X1_usingDTable_internal_body(
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const HUF_DTable* DTable)
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{
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BYTE* op = (BYTE*)dst;
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BYTE* const oend = op + dstSize;
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BYTE* const oend = ZSTD_maybeNullPtrAdd(op, dstSize);
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const void* dtPtr = DTable + 1;
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const HUF_DEltX1* const dt = (const HUF_DEltX1*)dtPtr;
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BIT_DStream_t bitD;
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@@ -575,6 +607,7 @@ HUF_decompress4X1_usingDTable_internal_body(
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{
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/* Check */
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if (cSrcSize < 10) return ERROR(corruption_detected); /* strict minimum : jump table + 1 byte per stream */
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if (dstSize < 6) return ERROR(corruption_detected); /* stream 4-split doesn't work */
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{ const BYTE* const istart = (const BYTE*) cSrc;
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BYTE* const ostart = (BYTE*) dst;
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@@ -610,7 +643,7 @@ HUF_decompress4X1_usingDTable_internal_body(
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if (length4 > cSrcSize) return ERROR(corruption_detected); /* overflow */
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if (opStart4 > oend) return ERROR(corruption_detected); /* overflow */
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if (dstSize < 6) return ERROR(corruption_detected); /* stream 4-split doesn't work */
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assert(dstSize >= 6); /* validated above */
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CHECK_F( BIT_initDStream(&bitD1, istart1, length1) );
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CHECK_F( BIT_initDStream(&bitD2, istart2, length2) );
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CHECK_F( BIT_initDStream(&bitD3, istart3, length3) );
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@@ -693,7 +726,7 @@ void HUF_decompress4X1_usingDTable_internal_fast_c_loop(HUF_DecompressFastArgs*
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BYTE* op[4];
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U16 const* const dtable = (U16 const*)args->dt;
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BYTE* const oend = args->oend;
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BYTE const* const ilimit = args->ilimit;
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BYTE const* const ilowest = args->ilowest;
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/* Copy the arguments to local variables */
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ZSTD_memcpy(&bits, &args->bits, sizeof(bits));
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@@ -706,13 +739,12 @@ void HUF_decompress4X1_usingDTable_internal_fast_c_loop(HUF_DecompressFastArgs*
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for (;;) {
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BYTE* olimit;
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int stream;
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int symbol;
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/* Assert loop preconditions */
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#ifndef NDEBUG
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for (stream = 0; stream < 4; ++stream) {
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assert(op[stream] <= (stream == 3 ? oend : op[stream + 1]));
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assert(ip[stream] >= ilimit);
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assert(ip[stream] >= ilowest);
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}
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#endif
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/* Compute olimit */
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@@ -722,7 +754,7 @@ void HUF_decompress4X1_usingDTable_internal_fast_c_loop(HUF_DecompressFastArgs*
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/* Each iteration consumes up to 11 bits * 5 = 55 bits < 7 bytes
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* per stream.
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*/
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size_t const iiters = (size_t)(ip[0] - ilimit) / 7;
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size_t const iiters = (size_t)(ip[0] - ilowest) / 7;
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/* We can safely run iters iterations before running bounds checks */
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size_t const iters = MIN(oiters, iiters);
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size_t const symbols = iters * 5;
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@@ -733,8 +765,8 @@ void HUF_decompress4X1_usingDTable_internal_fast_c_loop(HUF_DecompressFastArgs*
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*/
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olimit = op[3] + symbols;
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/* Exit fast decoding loop once we get close to the end. */
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if (op[3] + 20 > olimit)
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/* Exit fast decoding loop once we reach the end. */
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if (op[3] == olimit)
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break;
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/* Exit the decoding loop if any input pointer has crossed the
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@@ -753,27 +785,42 @@ void HUF_decompress4X1_usingDTable_internal_fast_c_loop(HUF_DecompressFastArgs*
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}
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#endif
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#define HUF_4X1_DECODE_SYMBOL(_stream, _symbol) \
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do { \
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int const index = (int)(bits[(_stream)] >> 53); \
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int const entry = (int)dtable[index]; \
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bits[(_stream)] <<= (entry & 0x3F); \
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op[(_stream)][(_symbol)] = (BYTE)((entry >> 8) & 0xFF); \
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} while (0)
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#define HUF_4X1_RELOAD_STREAM(_stream) \
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do { \
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int const ctz = ZSTD_countTrailingZeros64(bits[(_stream)]); \
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int const nbBits = ctz & 7; \
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int const nbBytes = ctz >> 3; \
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op[(_stream)] += 5; \
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ip[(_stream)] -= nbBytes; \
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bits[(_stream)] = MEM_read64(ip[(_stream)]) | 1; \
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bits[(_stream)] <<= nbBits; \
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} while (0)
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/* Manually unroll the loop because compilers don't consistently
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* unroll the inner loops, which destroys performance.
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*/
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do {
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/* Decode 5 symbols in each of the 4 streams */
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for (symbol = 0; symbol < 5; ++symbol) {
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for (stream = 0; stream < 4; ++stream) {
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int const index = (int)(bits[stream] >> 53);
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int const entry = (int)dtable[index];
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bits[stream] <<= (entry & 63);
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op[stream][symbol] = (BYTE)((entry >> 8) & 0xFF);
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}
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}
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/* Reload the bitstreams */
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for (stream = 0; stream < 4; ++stream) {
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int const ctz = ZSTD_countTrailingZeros64(bits[stream]);
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int const nbBits = ctz & 7;
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int const nbBytes = ctz >> 3;
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op[stream] += 5;
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ip[stream] -= nbBytes;
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bits[stream] = MEM_read64(ip[stream]) | 1;
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bits[stream] <<= nbBits;
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}
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HUF_4X_FOR_EACH_STREAM_WITH_VAR(HUF_4X1_DECODE_SYMBOL, 0);
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HUF_4X_FOR_EACH_STREAM_WITH_VAR(HUF_4X1_DECODE_SYMBOL, 1);
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HUF_4X_FOR_EACH_STREAM_WITH_VAR(HUF_4X1_DECODE_SYMBOL, 2);
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HUF_4X_FOR_EACH_STREAM_WITH_VAR(HUF_4X1_DECODE_SYMBOL, 3);
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HUF_4X_FOR_EACH_STREAM_WITH_VAR(HUF_4X1_DECODE_SYMBOL, 4);
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/* Reload each of the 4 the bitstreams */
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HUF_4X_FOR_EACH_STREAM(HUF_4X1_RELOAD_STREAM);
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} while (op[3] < olimit);
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#undef HUF_4X1_DECODE_SYMBOL
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#undef HUF_4X1_RELOAD_STREAM
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}
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_out:
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@@ -798,8 +845,8 @@ HUF_decompress4X1_usingDTable_internal_fast(
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HUF_DecompressFastLoopFn loopFn)
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{
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void const* dt = DTable + 1;
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const BYTE* const iend = (const BYTE*)cSrc + 6;
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BYTE* const oend = (BYTE*)dst + dstSize;
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BYTE const* const ilowest = (BYTE const*)cSrc;
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BYTE* const oend = ZSTD_maybeNullPtrAdd((BYTE*)dst, dstSize);
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HUF_DecompressFastArgs args;
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{ size_t const ret = HUF_DecompressFastArgs_init(&args, dst, dstSize, cSrc, cSrcSize, DTable);
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FORWARD_IF_ERROR(ret, "Failed to init fast loop args");
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@@ -807,18 +854,22 @@ HUF_decompress4X1_usingDTable_internal_fast(
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return 0;
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}
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assert(args.ip[0] >= args.ilimit);
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assert(args.ip[0] >= args.ilowest);
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loopFn(&args);
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/* Our loop guarantees that ip[] >= ilimit and that we haven't
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/* Our loop guarantees that ip[] >= ilowest and that we haven't
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* overwritten any op[].
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*/
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assert(args.ip[0] >= iend);
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assert(args.ip[1] >= iend);
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assert(args.ip[2] >= iend);
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assert(args.ip[3] >= iend);
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assert(args.ip[0] >= ilowest);
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assert(args.ip[0] >= ilowest);
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assert(args.ip[1] >= ilowest);
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assert(args.ip[2] >= ilowest);
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assert(args.ip[3] >= ilowest);
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assert(args.op[3] <= oend);
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(void)iend;
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assert(ilowest == args.ilowest);
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assert(ilowest + 6 == args.iend[0]);
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(void)ilowest;
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/* finish bit streams one by one. */
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{ size_t const segmentSize = (dstSize+3) / 4;
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@@ -869,7 +920,7 @@ static size_t HUF_decompress4X1_usingDTable_internal(void* dst, size_t dstSize,
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}
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#endif
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if (!(flags & HUF_flags_disableFast)) {
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if (HUF_ENABLE_FAST_DECODE && !(flags & HUF_flags_disableFast)) {
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size_t const ret = HUF_decompress4X1_usingDTable_internal_fast(dst, dstSize, cSrc, cSrcSize, DTable, loopFn);
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if (ret != 0)
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return ret;
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@@ -1240,15 +1291,19 @@ HUF_decodeLastSymbolX2(void* op, BIT_DStream_t* DStream, const HUF_DEltX2* dt, c
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}
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#define HUF_DECODE_SYMBOLX2_0(ptr, DStreamPtr) \
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ptr += HUF_decodeSymbolX2(ptr, DStreamPtr, dt, dtLog)
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do { ptr += HUF_decodeSymbolX2(ptr, DStreamPtr, dt, dtLog); } while (0)
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#define HUF_DECODE_SYMBOLX2_1(ptr, DStreamPtr) \
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if (MEM_64bits() || (HUF_TABLELOG_MAX<=12)) \
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ptr += HUF_decodeSymbolX2(ptr, DStreamPtr, dt, dtLog)
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#define HUF_DECODE_SYMBOLX2_1(ptr, DStreamPtr) \
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do { \
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if (MEM_64bits() || (HUF_TABLELOG_MAX<=12)) \
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ptr += HUF_decodeSymbolX2(ptr, DStreamPtr, dt, dtLog); \
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} while (0)
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#define HUF_DECODE_SYMBOLX2_2(ptr, DStreamPtr) \
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if (MEM_64bits()) \
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ptr += HUF_decodeSymbolX2(ptr, DStreamPtr, dt, dtLog)
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#define HUF_DECODE_SYMBOLX2_2(ptr, DStreamPtr) \
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do { \
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if (MEM_64bits()) \
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ptr += HUF_decodeSymbolX2(ptr, DStreamPtr, dt, dtLog); \
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} while (0)
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HINT_INLINE size_t
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HUF_decodeStreamX2(BYTE* p, BIT_DStream_t* bitDPtr, BYTE* const pEnd,
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@@ -1308,7 +1363,7 @@ HUF_decompress1X2_usingDTable_internal_body(
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/* decode */
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{ BYTE* const ostart = (BYTE*) dst;
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BYTE* const oend = ostart + dstSize;
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BYTE* const oend = ZSTD_maybeNullPtrAdd(ostart, dstSize);
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const void* const dtPtr = DTable+1; /* force compiler to not use strict-aliasing */
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const HUF_DEltX2* const dt = (const HUF_DEltX2*)dtPtr;
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DTableDesc const dtd = HUF_getDTableDesc(DTable);
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@@ -1333,6 +1388,7 @@ HUF_decompress4X2_usingDTable_internal_body(
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const HUF_DTable* DTable)
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{
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||||
if (cSrcSize < 10) return ERROR(corruption_detected); /* strict minimum : jump table + 1 byte per stream */
|
||||
if (dstSize < 6) return ERROR(corruption_detected); /* stream 4-split doesn't work */
|
||||
|
||||
{ const BYTE* const istart = (const BYTE*) cSrc;
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||||
BYTE* const ostart = (BYTE*) dst;
|
||||
@@ -1368,7 +1424,7 @@ HUF_decompress4X2_usingDTable_internal_body(
|
||||
|
||||
if (length4 > cSrcSize) return ERROR(corruption_detected); /* overflow */
|
||||
if (opStart4 > oend) return ERROR(corruption_detected); /* overflow */
|
||||
if (dstSize < 6) return ERROR(corruption_detected); /* stream 4-split doesn't work */
|
||||
assert(dstSize >= 6 /* validated above */);
|
||||
CHECK_F( BIT_initDStream(&bitD1, istart1, length1) );
|
||||
CHECK_F( BIT_initDStream(&bitD2, istart2, length2) );
|
||||
CHECK_F( BIT_initDStream(&bitD3, istart3, length3) );
|
||||
@@ -1473,7 +1529,7 @@ void HUF_decompress4X2_usingDTable_internal_fast_c_loop(HUF_DecompressFastArgs*
|
||||
BYTE* op[4];
|
||||
BYTE* oend[4];
|
||||
HUF_DEltX2 const* const dtable = (HUF_DEltX2 const*)args->dt;
|
||||
BYTE const* const ilimit = args->ilimit;
|
||||
BYTE const* const ilowest = args->ilowest;
|
||||
|
||||
/* Copy the arguments to local registers. */
|
||||
ZSTD_memcpy(&bits, &args->bits, sizeof(bits));
|
||||
@@ -1491,13 +1547,12 @@ void HUF_decompress4X2_usingDTable_internal_fast_c_loop(HUF_DecompressFastArgs*
|
||||
for (;;) {
|
||||
BYTE* olimit;
|
||||
int stream;
|
||||
int symbol;
|
||||
|
||||
/* Assert loop preconditions */
|
||||
#ifndef NDEBUG
|
||||
for (stream = 0; stream < 4; ++stream) {
|
||||
assert(op[stream] <= oend[stream]);
|
||||
assert(ip[stream] >= ilimit);
|
||||
assert(ip[stream] >= ilowest);
|
||||
}
|
||||
#endif
|
||||
/* Compute olimit */
|
||||
@@ -1510,7 +1565,7 @@ void HUF_decompress4X2_usingDTable_internal_fast_c_loop(HUF_DecompressFastArgs*
|
||||
* We also know that each input pointer is >= ip[0]. So we can run
|
||||
* iters loops before running out of input.
|
||||
*/
|
||||
size_t iters = (size_t)(ip[0] - ilimit) / 7;
|
||||
size_t iters = (size_t)(ip[0] - ilowest) / 7;
|
||||
/* Each iteration can produce up to 10 bytes of output per stream.
|
||||
* Each output stream my advance at different rates. So take the
|
||||
* minimum number of safe iterations among all the output streams.
|
||||
@@ -1528,8 +1583,8 @@ void HUF_decompress4X2_usingDTable_internal_fast_c_loop(HUF_DecompressFastArgs*
|
||||
*/
|
||||
olimit = op[3] + (iters * 5);
|
||||
|
||||
/* Exit the fast decoding loop if we are too close to the end. */
|
||||
if (op[3] + 10 > olimit)
|
||||
/* Exit the fast decoding loop once we reach the end. */
|
||||
if (op[3] == olimit)
|
||||
break;
|
||||
|
||||
/* Exit the decoding loop if any input pointer has crossed the
|
||||
@@ -1548,54 +1603,58 @@ void HUF_decompress4X2_usingDTable_internal_fast_c_loop(HUF_DecompressFastArgs*
|
||||
}
|
||||
#endif
|
||||
|
||||
#define HUF_4X2_DECODE_SYMBOL(_stream, _decode3) \
|
||||
do { \
|
||||
if ((_decode3) || (_stream) != 3) { \
|
||||
int const index = (int)(bits[(_stream)] >> 53); \
|
||||
HUF_DEltX2 const entry = dtable[index]; \
|
||||
MEM_write16(op[(_stream)], entry.sequence); \
|
||||
bits[(_stream)] <<= (entry.nbBits) & 0x3F; \
|
||||
op[(_stream)] += (entry.length); \
|
||||
} \
|
||||
} while (0)
|
||||
|
||||
#define HUF_4X2_RELOAD_STREAM(_stream) \
|
||||
do { \
|
||||
HUF_4X2_DECODE_SYMBOL(3, 1); \
|
||||
{ \
|
||||
int const ctz = ZSTD_countTrailingZeros64(bits[(_stream)]); \
|
||||
int const nbBits = ctz & 7; \
|
||||
int const nbBytes = ctz >> 3; \
|
||||
ip[(_stream)] -= nbBytes; \
|
||||
bits[(_stream)] = MEM_read64(ip[(_stream)]) | 1; \
|
||||
bits[(_stream)] <<= nbBits; \
|
||||
} \
|
||||
} while (0)
|
||||
|
||||
/* Manually unroll the loop because compilers don't consistently
|
||||
* unroll the inner loops, which destroys performance.
|
||||
*/
|
||||
do {
|
||||
/* Do 5 table lookups for each of the first 3 streams */
|
||||
for (symbol = 0; symbol < 5; ++symbol) {
|
||||
for (stream = 0; stream < 3; ++stream) {
|
||||
int const index = (int)(bits[stream] >> 53);
|
||||
HUF_DEltX2 const entry = dtable[index];
|
||||
MEM_write16(op[stream], entry.sequence);
|
||||
bits[stream] <<= (entry.nbBits);
|
||||
op[stream] += (entry.length);
|
||||
}
|
||||
}
|
||||
/* Do 1 table lookup from the final stream */
|
||||
{
|
||||
int const index = (int)(bits[3] >> 53);
|
||||
HUF_DEltX2 const entry = dtable[index];
|
||||
MEM_write16(op[3], entry.sequence);
|
||||
bits[3] <<= (entry.nbBits);
|
||||
op[3] += (entry.length);
|
||||
}
|
||||
/* Do 4 table lookups from the final stream & reload bitstreams */
|
||||
for (stream = 0; stream < 4; ++stream) {
|
||||
/* Do a table lookup from the final stream.
|
||||
* This is interleaved with the reloading to reduce register
|
||||
* pressure. This shouldn't be necessary, but compilers can
|
||||
* struggle with codegen with high register pressure.
|
||||
*/
|
||||
{
|
||||
int const index = (int)(bits[3] >> 53);
|
||||
HUF_DEltX2 const entry = dtable[index];
|
||||
MEM_write16(op[3], entry.sequence);
|
||||
bits[3] <<= (entry.nbBits);
|
||||
op[3] += (entry.length);
|
||||
}
|
||||
/* Reload the bistreams. The final bitstream must be reloaded
|
||||
* after the 5th symbol was decoded.
|
||||
*/
|
||||
{
|
||||
int const ctz = ZSTD_countTrailingZeros64(bits[stream]);
|
||||
int const nbBits = ctz & 7;
|
||||
int const nbBytes = ctz >> 3;
|
||||
ip[stream] -= nbBytes;
|
||||
bits[stream] = MEM_read64(ip[stream]) | 1;
|
||||
bits[stream] <<= nbBits;
|
||||
}
|
||||
}
|
||||
/* Decode 5 symbols from each of the first 3 streams.
|
||||
* The final stream will be decoded during the reload phase
|
||||
* to reduce register pressure.
|
||||
*/
|
||||
HUF_4X_FOR_EACH_STREAM_WITH_VAR(HUF_4X2_DECODE_SYMBOL, 0);
|
||||
HUF_4X_FOR_EACH_STREAM_WITH_VAR(HUF_4X2_DECODE_SYMBOL, 0);
|
||||
HUF_4X_FOR_EACH_STREAM_WITH_VAR(HUF_4X2_DECODE_SYMBOL, 0);
|
||||
HUF_4X_FOR_EACH_STREAM_WITH_VAR(HUF_4X2_DECODE_SYMBOL, 0);
|
||||
HUF_4X_FOR_EACH_STREAM_WITH_VAR(HUF_4X2_DECODE_SYMBOL, 0);
|
||||
|
||||
/* Decode one symbol from the final stream */
|
||||
HUF_4X2_DECODE_SYMBOL(3, 1);
|
||||
|
||||
/* Decode 4 symbols from the final stream & reload bitstreams.
|
||||
* The final stream is reloaded last, meaning that all 5 symbols
|
||||
* are decoded from the final stream before it is reloaded.
|
||||
*/
|
||||
HUF_4X_FOR_EACH_STREAM(HUF_4X2_RELOAD_STREAM);
|
||||
} while (op[3] < olimit);
|
||||
}
|
||||
|
||||
#undef HUF_4X2_DECODE_SYMBOL
|
||||
#undef HUF_4X2_RELOAD_STREAM
|
||||
|
||||
_out:
|
||||
|
||||
/* Save the final values of each of the state variables back to args. */
|
||||
@@ -1612,8 +1671,8 @@ HUF_decompress4X2_usingDTable_internal_fast(
|
||||
const HUF_DTable* DTable,
|
||||
HUF_DecompressFastLoopFn loopFn) {
|
||||
void const* dt = DTable + 1;
|
||||
const BYTE* const iend = (const BYTE*)cSrc + 6;
|
||||
BYTE* const oend = (BYTE*)dst + dstSize;
|
||||
const BYTE* const ilowest = (const BYTE*)cSrc;
|
||||
BYTE* const oend = ZSTD_maybeNullPtrAdd((BYTE*)dst, dstSize);
|
||||
HUF_DecompressFastArgs args;
|
||||
{
|
||||
size_t const ret = HUF_DecompressFastArgs_init(&args, dst, dstSize, cSrc, cSrcSize, DTable);
|
||||
@@ -1622,16 +1681,19 @@ HUF_decompress4X2_usingDTable_internal_fast(
|
||||
return 0;
|
||||
}
|
||||
|
||||
assert(args.ip[0] >= args.ilimit);
|
||||
assert(args.ip[0] >= args.ilowest);
|
||||
loopFn(&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.ip[0] >= ilowest);
|
||||
assert(args.ip[1] >= ilowest);
|
||||
assert(args.ip[2] >= ilowest);
|
||||
assert(args.ip[3] >= ilowest);
|
||||
assert(args.op[3] <= oend);
|
||||
(void)iend;
|
||||
|
||||
assert(ilowest == args.ilowest);
|
||||
assert(ilowest + 6 == args.iend[0]);
|
||||
(void)ilowest;
|
||||
|
||||
/* finish bitStreams one by one */
|
||||
{
|
||||
@@ -1680,7 +1742,7 @@ static size_t HUF_decompress4X2_usingDTable_internal(void* dst, size_t dstSize,
|
||||
}
|
||||
#endif
|
||||
|
||||
if (!(flags & HUF_flags_disableFast)) {
|
||||
if (HUF_ENABLE_FAST_DECODE && !(flags & HUF_flags_disableFast)) {
|
||||
size_t const ret = HUF_decompress4X2_usingDTable_internal_fast(dst, dstSize, cSrc, cSrcSize, DTable, loopFn);
|
||||
if (ret != 0)
|
||||
return ret;
|
||||
|
||||
Reference in New Issue
Block a user