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Zstd: Update bundled library to v1.5.7 without further adjustments
This commit only replaces the bundled source and does not include any ZFS integration changes. Because the build depends on integration adjustments, it will fail until the accompanying integration commit is applied. Upstream release: https://github.com/facebook/zstd/releases/tag/v1.5.7 Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Alexander Moch <mail@alexmoch.com> Closes #18089
This commit is contained in:
committed by
Brian Behlendorf
parent
54b141fab5
commit
bbcddb127a
+104
-105
@@ -1,8 +1,7 @@
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// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0-only
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/* ******************************************************************
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* bitstream
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* Part of FSE library
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* Copyright (c) 2013-2020, Yann Collet, Facebook, Inc.
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* Copyright (c) Meta Platforms, Inc. and affiliates.
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*
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* You can contact the author at :
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* - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
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@@ -15,10 +14,6 @@
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#ifndef BITSTREAM_H_MODULE
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#define BITSTREAM_H_MODULE
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#if defined (__cplusplus)
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extern "C" {
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#endif
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/*
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* This API consists of small unitary functions, which must be inlined for best performance.
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* Since link-time-optimization is not available for all compilers,
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@@ -32,15 +27,17 @@ extern "C" {
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#include "compiler.h" /* UNLIKELY() */
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#include "debug.h" /* assert(), DEBUGLOG(), RAWLOG() */
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#include "error_private.h" /* error codes and messages */
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#include "bits.h" /* ZSTD_highbit32 */
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/*=========================================
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* Target specific
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=========================================*/
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#if defined(__BMI__) && defined(__GNUC__)
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# include <immintrin.h> /* support for bextr (experimental) */
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#elif defined(__ICCARM__)
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# include <intrinsics.h>
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#ifndef ZSTD_NO_INTRINSICS
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# if (defined(__BMI__) || defined(__BMI2__)) && defined(__GNUC__)
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# include <immintrin.h> /* support for bextr (experimental)/bzhi */
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# elif defined(__ICCARM__)
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# include <intrinsics.h>
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# endif
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#endif
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#define STREAM_ACCUMULATOR_MIN_32 25
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@@ -51,12 +48,13 @@ extern "C" {
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/*-******************************************
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* bitStream encoding API (write forward)
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********************************************/
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typedef size_t BitContainerType;
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/* bitStream can mix input from multiple sources.
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* A critical property of these streams is that they encode and decode in **reverse** direction.
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* So the first bit sequence you add will be the last to be read, like a LIFO stack.
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*/
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typedef struct {
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size_t bitContainer;
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BitContainerType bitContainer;
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unsigned bitPos;
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char* startPtr;
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char* ptr;
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@@ -64,7 +62,7 @@ typedef struct {
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} BIT_CStream_t;
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MEM_STATIC size_t BIT_initCStream(BIT_CStream_t* bitC, void* dstBuffer, size_t dstCapacity);
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MEM_STATIC void BIT_addBits(BIT_CStream_t* bitC, size_t value, unsigned nbBits);
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MEM_STATIC void BIT_addBits(BIT_CStream_t* bitC, BitContainerType value, unsigned nbBits);
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MEM_STATIC void BIT_flushBits(BIT_CStream_t* bitC);
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MEM_STATIC size_t BIT_closeCStream(BIT_CStream_t* bitC);
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@@ -73,7 +71,7 @@ MEM_STATIC size_t BIT_closeCStream(BIT_CStream_t* bitC);
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* `dstCapacity` must be >= sizeof(bitD->bitContainer), otherwise @return will be an error code.
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*
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* bits are first added to a local register.
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* Local register is size_t, hence 64-bits on 64-bits systems, or 32-bits on 32-bits systems.
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* Local register is BitContainerType, 64-bits on 64-bits systems, or 32-bits on 32-bits systems.
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* Writing data into memory is an explicit operation, performed by the flushBits function.
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* Hence keep track how many bits are potentially stored into local register to avoid register overflow.
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* After a flushBits, a maximum of 7 bits might still be stored into local register.
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@@ -90,28 +88,28 @@ MEM_STATIC size_t BIT_closeCStream(BIT_CStream_t* bitC);
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* bitStream decoding API (read backward)
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**********************************************/
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typedef struct {
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size_t bitContainer;
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BitContainerType bitContainer;
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unsigned bitsConsumed;
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const char* ptr;
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const char* start;
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const char* limitPtr;
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} BIT_DStream_t;
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typedef enum { BIT_DStream_unfinished = 0,
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BIT_DStream_endOfBuffer = 1,
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BIT_DStream_completed = 2,
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BIT_DStream_overflow = 3 } BIT_DStream_status; /* result of BIT_reloadDStream() */
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/* 1,2,4,8 would be better for bitmap combinations, but slows down performance a bit ... :( */
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typedef enum { BIT_DStream_unfinished = 0, /* fully refilled */
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BIT_DStream_endOfBuffer = 1, /* still some bits left in bitstream */
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BIT_DStream_completed = 2, /* bitstream entirely consumed, bit-exact */
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BIT_DStream_overflow = 3 /* user requested more bits than present in bitstream */
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} BIT_DStream_status; /* result of BIT_reloadDStream() */
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MEM_STATIC size_t BIT_initDStream(BIT_DStream_t* bitD, const void* srcBuffer, size_t srcSize);
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MEM_STATIC size_t BIT_readBits(BIT_DStream_t* bitD, unsigned nbBits);
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MEM_STATIC BitContainerType BIT_readBits(BIT_DStream_t* bitD, unsigned nbBits);
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MEM_STATIC BIT_DStream_status BIT_reloadDStream(BIT_DStream_t* bitD);
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MEM_STATIC unsigned BIT_endOfDStream(const BIT_DStream_t* bitD);
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/* Start by invoking BIT_initDStream().
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* A chunk of the bitStream is then stored into a local register.
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* Local register size is 64-bits on 64-bits systems, 32-bits on 32-bits systems (size_t).
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* Local register size is 64-bits on 64-bits systems, 32-bits on 32-bits systems (BitContainerType).
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* You can then retrieve bitFields stored into the local register, **in reverse order**.
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* Local register is explicitly reloaded from memory by the BIT_reloadDStream() method.
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* A reload guarantee a minimum of ((8*sizeof(bitD->bitContainer))-7) bits when its result is BIT_DStream_unfinished.
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@@ -123,7 +121,7 @@ MEM_STATIC unsigned BIT_endOfDStream(const BIT_DStream_t* bitD);
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/*-****************************************
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* unsafe API
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******************************************/
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MEM_STATIC void BIT_addBitsFast(BIT_CStream_t* bitC, size_t value, unsigned nbBits);
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MEM_STATIC void BIT_addBitsFast(BIT_CStream_t* bitC, BitContainerType value, unsigned nbBits);
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/* faster, but works only if value is "clean", meaning all high bits above nbBits are 0 */
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MEM_STATIC void BIT_flushBitsFast(BIT_CStream_t* bitC);
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@@ -132,38 +130,6 @@ MEM_STATIC void BIT_flushBitsFast(BIT_CStream_t* bitC);
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MEM_STATIC size_t BIT_readBitsFast(BIT_DStream_t* bitD, unsigned nbBits);
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/* faster, but works only if nbBits >= 1 */
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/*-**************************************************************
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* Internal functions
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****************************************************************/
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MEM_STATIC unsigned BIT_highbit32 (U32 val)
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{
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assert(val != 0);
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{
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# if defined(_MSC_VER) /* Visual */
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unsigned long r=0;
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return _BitScanReverse ( &r, val ) ? (unsigned)r : 0;
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# elif defined(__GNUC__) && (__GNUC__ >= 3) /* Use GCC Intrinsic */
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return __builtin_clz (val) ^ 31;
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# elif defined(__ICCARM__) /* IAR Intrinsic */
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return 31 - __CLZ(val);
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# else /* Software version */
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static const unsigned DeBruijnClz[32] = { 0, 9, 1, 10, 13, 21, 2, 29,
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11, 14, 16, 18, 22, 25, 3, 30,
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8, 12, 20, 28, 15, 17, 24, 7,
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19, 27, 23, 6, 26, 5, 4, 31 };
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U32 v = val;
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v |= v >> 1;
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v |= v >> 2;
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v |= v >> 4;
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v |= v >> 8;
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v |= v >> 16;
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return DeBruijnClz[ (U32) (v * 0x07C4ACDDU) >> 27];
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# endif
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}
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}
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/*===== Local Constants =====*/
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static const unsigned BIT_mask[] = {
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0, 1, 3, 7, 0xF, 0x1F,
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@@ -193,16 +159,31 @@ MEM_STATIC size_t BIT_initCStream(BIT_CStream_t* bitC,
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return 0;
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}
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FORCE_INLINE_TEMPLATE BitContainerType BIT_getLowerBits(BitContainerType bitContainer, U32 const nbBits)
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{
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#if STATIC_BMI2 && !defined(ZSTD_NO_INTRINSICS)
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# if (defined(__x86_64__) || defined(_M_X64)) && !defined(__ILP32__)
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return _bzhi_u64(bitContainer, nbBits);
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# else
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DEBUG_STATIC_ASSERT(sizeof(bitContainer) == sizeof(U32));
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return _bzhi_u32(bitContainer, nbBits);
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# endif
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#else
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assert(nbBits < BIT_MASK_SIZE);
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return bitContainer & BIT_mask[nbBits];
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#endif
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}
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/*! BIT_addBits() :
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* can add up to 31 bits into `bitC`.
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* Note : does not check for register overflow ! */
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MEM_STATIC void BIT_addBits(BIT_CStream_t* bitC,
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size_t value, unsigned nbBits)
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BitContainerType value, unsigned nbBits)
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{
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MEM_STATIC_ASSERT(BIT_MASK_SIZE == 32);
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DEBUG_STATIC_ASSERT(BIT_MASK_SIZE == 32);
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assert(nbBits < BIT_MASK_SIZE);
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assert(nbBits + bitC->bitPos < sizeof(bitC->bitContainer) * 8);
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bitC->bitContainer |= (value & BIT_mask[nbBits]) << bitC->bitPos;
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bitC->bitContainer |= BIT_getLowerBits(value, nbBits) << bitC->bitPos;
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bitC->bitPos += nbBits;
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}
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@@ -210,7 +191,7 @@ MEM_STATIC void BIT_addBits(BIT_CStream_t* bitC,
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* works only if `value` is _clean_,
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* meaning all high bits above nbBits are 0 */
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MEM_STATIC void BIT_addBitsFast(BIT_CStream_t* bitC,
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size_t value, unsigned nbBits)
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BitContainerType value, unsigned nbBits)
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{
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assert((value>>nbBits) == 0);
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assert(nbBits + bitC->bitPos < sizeof(bitC->bitContainer) * 8);
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@@ -257,7 +238,7 @@ MEM_STATIC size_t BIT_closeCStream(BIT_CStream_t* bitC)
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BIT_addBitsFast(bitC, 1, 1); /* endMark */
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BIT_flushBits(bitC);
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if (bitC->ptr >= bitC->endPtr) return 0; /* overflow detected */
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return (bitC->ptr - bitC->startPtr) + (bitC->bitPos > 0);
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return (size_t)(bitC->ptr - bitC->startPtr) + (bitC->bitPos > 0);
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}
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@@ -272,7 +253,7 @@ MEM_STATIC size_t BIT_closeCStream(BIT_CStream_t* bitC)
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*/
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MEM_STATIC size_t BIT_initDStream(BIT_DStream_t* bitD, const void* srcBuffer, size_t srcSize)
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{
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if (srcSize < 1) { memset(bitD, 0, sizeof(*bitD)); return ERROR(srcSize_wrong); }
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if (srcSize < 1) { ZSTD_memset(bitD, 0, sizeof(*bitD)); return ERROR(srcSize_wrong); }
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bitD->start = (const char*)srcBuffer;
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bitD->limitPtr = bitD->start + sizeof(bitD->bitContainer);
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@@ -281,35 +262,35 @@ MEM_STATIC size_t BIT_initDStream(BIT_DStream_t* bitD, const void* srcBuffer, si
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bitD->ptr = (const char*)srcBuffer + srcSize - sizeof(bitD->bitContainer);
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bitD->bitContainer = MEM_readLEST(bitD->ptr);
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{ BYTE const lastByte = ((const BYTE*)srcBuffer)[srcSize-1];
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bitD->bitsConsumed = lastByte ? 8 - BIT_highbit32(lastByte) : 0; /* ensures bitsConsumed is always set */
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bitD->bitsConsumed = lastByte ? 8 - ZSTD_highbit32(lastByte) : 0; /* ensures bitsConsumed is always set */
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if (lastByte == 0) return ERROR(GENERIC); /* endMark not present */ }
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} else {
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bitD->ptr = bitD->start;
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bitD->bitContainer = *(const BYTE*)(bitD->start);
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switch(srcSize)
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{
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case 7: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[6]) << (sizeof(bitD->bitContainer)*8 - 16);
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/* fall-through */
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case 7: bitD->bitContainer += (BitContainerType)(((const BYTE*)(srcBuffer))[6]) << (sizeof(bitD->bitContainer)*8 - 16);
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ZSTD_FALLTHROUGH;
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case 6: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[5]) << (sizeof(bitD->bitContainer)*8 - 24);
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/* fall-through */
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case 6: bitD->bitContainer += (BitContainerType)(((const BYTE*)(srcBuffer))[5]) << (sizeof(bitD->bitContainer)*8 - 24);
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ZSTD_FALLTHROUGH;
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case 5: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[4]) << (sizeof(bitD->bitContainer)*8 - 32);
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/* fall-through */
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case 5: bitD->bitContainer += (BitContainerType)(((const BYTE*)(srcBuffer))[4]) << (sizeof(bitD->bitContainer)*8 - 32);
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ZSTD_FALLTHROUGH;
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case 4: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[3]) << 24;
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/* fall-through */
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case 4: bitD->bitContainer += (BitContainerType)(((const BYTE*)(srcBuffer))[3]) << 24;
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ZSTD_FALLTHROUGH;
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case 3: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[2]) << 16;
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/* fall-through */
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case 3: bitD->bitContainer += (BitContainerType)(((const BYTE*)(srcBuffer))[2]) << 16;
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ZSTD_FALLTHROUGH;
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case 2: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[1]) << 8;
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/* fall-through */
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case 2: bitD->bitContainer += (BitContainerType)(((const BYTE*)(srcBuffer))[1]) << 8;
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ZSTD_FALLTHROUGH;
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default: break;
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}
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{ BYTE const lastByte = ((const BYTE*)srcBuffer)[srcSize-1];
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bitD->bitsConsumed = lastByte ? 8 - BIT_highbit32(lastByte) : 0;
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bitD->bitsConsumed = lastByte ? 8 - ZSTD_highbit32(lastByte) : 0;
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if (lastByte == 0) return ERROR(corruption_detected); /* endMark not present */
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}
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bitD->bitsConsumed += (U32)(sizeof(bitD->bitContainer) - srcSize)*8;
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@@ -318,23 +299,26 @@ MEM_STATIC size_t BIT_initDStream(BIT_DStream_t* bitD, const void* srcBuffer, si
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return srcSize;
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}
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MEM_STATIC size_t BIT_getUpperBits(size_t bitContainer, U32 const start)
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FORCE_INLINE_TEMPLATE BitContainerType BIT_getUpperBits(BitContainerType bitContainer, U32 const start)
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{
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return bitContainer >> start;
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}
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MEM_STATIC size_t BIT_getMiddleBits(size_t bitContainer, U32 const start, U32 const nbBits)
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FORCE_INLINE_TEMPLATE BitContainerType BIT_getMiddleBits(BitContainerType bitContainer, U32 const start, U32 const nbBits)
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{
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U32 const regMask = sizeof(bitContainer)*8 - 1;
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/* if start > regMask, bitstream is corrupted, and result is undefined */
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assert(nbBits < BIT_MASK_SIZE);
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/* x86 transform & ((1 << nbBits) - 1) to bzhi instruction, it is better
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* than accessing memory. When bmi2 instruction is not present, we consider
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* such cpus old (pre-Haswell, 2013) and their performance is not of that
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* importance.
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*/
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#if defined(__x86_64__) || defined(_M_X64)
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return (bitContainer >> (start & regMask)) & ((((U64)1) << nbBits) - 1);
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#else
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return (bitContainer >> (start & regMask)) & BIT_mask[nbBits];
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}
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MEM_STATIC size_t BIT_getLowerBits(size_t bitContainer, U32 const nbBits)
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{
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assert(nbBits < BIT_MASK_SIZE);
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return bitContainer & BIT_mask[nbBits];
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#endif
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}
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/*! BIT_lookBits() :
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@@ -343,7 +327,7 @@ MEM_STATIC size_t BIT_getLowerBits(size_t bitContainer, U32 const nbBits)
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* On 32-bits, maxNbBits==24.
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* On 64-bits, maxNbBits==56.
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* @return : value extracted */
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MEM_STATIC size_t BIT_lookBits(const BIT_DStream_t* bitD, U32 nbBits)
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FORCE_INLINE_TEMPLATE BitContainerType BIT_lookBits(const BIT_DStream_t* bitD, U32 nbBits)
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{
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/* arbitrate between double-shift and shift+mask */
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#if 1
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@@ -359,14 +343,14 @@ MEM_STATIC size_t BIT_lookBits(const BIT_DStream_t* bitD, U32 nbBits)
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/*! BIT_lookBitsFast() :
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* unsafe version; only works if nbBits >= 1 */
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MEM_STATIC size_t BIT_lookBitsFast(const BIT_DStream_t* bitD, U32 nbBits)
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MEM_STATIC BitContainerType BIT_lookBitsFast(const BIT_DStream_t* bitD, U32 nbBits)
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{
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U32 const regMask = sizeof(bitD->bitContainer)*8 - 1;
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assert(nbBits >= 1);
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return (bitD->bitContainer << (bitD->bitsConsumed & regMask)) >> (((regMask+1)-nbBits) & regMask);
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}
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MEM_STATIC void BIT_skipBits(BIT_DStream_t* bitD, U32 nbBits)
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FORCE_INLINE_TEMPLATE void BIT_skipBits(BIT_DStream_t* bitD, U32 nbBits)
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{
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bitD->bitsConsumed += nbBits;
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}
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@@ -375,23 +359,38 @@ MEM_STATIC void BIT_skipBits(BIT_DStream_t* bitD, U32 nbBits)
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* Read (consume) next n bits from local register and update.
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* Pay attention to not read more than nbBits contained into local register.
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* @return : extracted value. */
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MEM_STATIC size_t BIT_readBits(BIT_DStream_t* bitD, unsigned nbBits)
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FORCE_INLINE_TEMPLATE BitContainerType BIT_readBits(BIT_DStream_t* bitD, unsigned nbBits)
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{
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size_t const value = BIT_lookBits(bitD, nbBits);
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BitContainerType const value = BIT_lookBits(bitD, nbBits);
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BIT_skipBits(bitD, nbBits);
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return value;
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}
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/*! BIT_readBitsFast() :
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* unsafe version; only works only if nbBits >= 1 */
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MEM_STATIC size_t BIT_readBitsFast(BIT_DStream_t* bitD, unsigned nbBits)
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* unsafe version; only works if nbBits >= 1 */
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MEM_STATIC BitContainerType BIT_readBitsFast(BIT_DStream_t* bitD, unsigned nbBits)
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{
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size_t const value = BIT_lookBitsFast(bitD, nbBits);
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BitContainerType const value = BIT_lookBitsFast(bitD, nbBits);
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assert(nbBits >= 1);
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BIT_skipBits(bitD, nbBits);
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return value;
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}
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/*! BIT_reloadDStream_internal() :
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* Simple variant of BIT_reloadDStream(), with two conditions:
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* 1. bitstream is valid : bitsConsumed <= sizeof(bitD->bitContainer)*8
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* 2. look window is valid after shifted down : bitD->ptr >= bitD->start
|
||||
*/
|
||||
MEM_STATIC BIT_DStream_status BIT_reloadDStream_internal(BIT_DStream_t* bitD)
|
||||
{
|
||||
assert(bitD->bitsConsumed <= sizeof(bitD->bitContainer)*8);
|
||||
bitD->ptr -= bitD->bitsConsumed >> 3;
|
||||
assert(bitD->ptr >= bitD->start);
|
||||
bitD->bitsConsumed &= 7;
|
||||
bitD->bitContainer = MEM_readLEST(bitD->ptr);
|
||||
return BIT_DStream_unfinished;
|
||||
}
|
||||
|
||||
/*! BIT_reloadDStreamFast() :
|
||||
* Similar to BIT_reloadDStream(), but with two differences:
|
||||
* 1. bitsConsumed <= sizeof(bitD->bitContainer)*8 must hold!
|
||||
@@ -402,31 +401,35 @@ MEM_STATIC BIT_DStream_status BIT_reloadDStreamFast(BIT_DStream_t* bitD)
|
||||
{
|
||||
if (UNLIKELY(bitD->ptr < bitD->limitPtr))
|
||||
return BIT_DStream_overflow;
|
||||
assert(bitD->bitsConsumed <= sizeof(bitD->bitContainer)*8);
|
||||
bitD->ptr -= bitD->bitsConsumed >> 3;
|
||||
bitD->bitsConsumed &= 7;
|
||||
bitD->bitContainer = MEM_readLEST(bitD->ptr);
|
||||
return BIT_DStream_unfinished;
|
||||
return BIT_reloadDStream_internal(bitD);
|
||||
}
|
||||
|
||||
/*! BIT_reloadDStream() :
|
||||
* Refill `bitD` from buffer previously set in BIT_initDStream() .
|
||||
* This function is safe, it guarantees it will not read beyond src buffer.
|
||||
* This function is safe, it guarantees it will not never beyond src buffer.
|
||||
* @return : status of `BIT_DStream_t` internal register.
|
||||
* when status == BIT_DStream_unfinished, internal register is filled with at least 25 or 57 bits */
|
||||
MEM_STATIC BIT_DStream_status BIT_reloadDStream(BIT_DStream_t* bitD)
|
||||
FORCE_INLINE_TEMPLATE BIT_DStream_status BIT_reloadDStream(BIT_DStream_t* bitD)
|
||||
{
|
||||
if (bitD->bitsConsumed > (sizeof(bitD->bitContainer)*8)) /* overflow detected, like end of stream */
|
||||
/* note : once in overflow mode, a bitstream remains in this mode until it's reset */
|
||||
if (UNLIKELY(bitD->bitsConsumed > (sizeof(bitD->bitContainer)*8))) {
|
||||
static const BitContainerType zeroFilled = 0;
|
||||
bitD->ptr = (const char*)&zeroFilled; /* aliasing is allowed for char */
|
||||
/* overflow detected, erroneous scenario or end of stream: no update */
|
||||
return BIT_DStream_overflow;
|
||||
}
|
||||
|
||||
assert(bitD->ptr >= bitD->start);
|
||||
|
||||
if (bitD->ptr >= bitD->limitPtr) {
|
||||
return BIT_reloadDStreamFast(bitD);
|
||||
return BIT_reloadDStream_internal(bitD);
|
||||
}
|
||||
if (bitD->ptr == bitD->start) {
|
||||
/* reached end of bitStream => no update */
|
||||
if (bitD->bitsConsumed < sizeof(bitD->bitContainer)*8) return BIT_DStream_endOfBuffer;
|
||||
return BIT_DStream_completed;
|
||||
}
|
||||
/* start < ptr < limitPtr */
|
||||
/* start < ptr < limitPtr => cautious update */
|
||||
{ U32 nbBytes = bitD->bitsConsumed >> 3;
|
||||
BIT_DStream_status result = BIT_DStream_unfinished;
|
||||
if (bitD->ptr - nbBytes < bitD->start) {
|
||||
@@ -448,8 +451,4 @@ MEM_STATIC unsigned BIT_endOfDStream(const BIT_DStream_t* DStream)
|
||||
return ((DStream->ptr == DStream->start) && (DStream->bitsConsumed == sizeof(DStream->bitContainer)*8));
|
||||
}
|
||||
|
||||
#if defined (__cplusplus)
|
||||
}
|
||||
#endif
|
||||
|
||||
#endif /* BITSTREAM_H_MODULE */
|
||||
|
||||
Reference in New Issue
Block a user