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[linux-kernel] Update patches for v2

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* Reduce stack usage of many zstd functions, none use over 388 B anymore.
* Remove an incorrect `const` in `xxhash`.
This commit is contained in:
Nick Terrell
2017-06-28 22:01:46 -07:00
parent 379f9d874d
commit ce91b64f00
18 changed files with 691 additions and 456 deletions
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contrib/linux-kernel/lib/zstd/fse_decompress.c
+26 -7
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@@ -48,6 +48,7 @@
#include "bitstream.h"
#include "fse.h"
#include <linux/compiler.h>
#include <linux/kernel.h>
#include <linux/string.h> /* memcpy, memset */
/* **************************************************************
@@ -91,17 +92,19 @@
/* Function templates */
size_t FSE_buildDTable(FSE_DTable *dt, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog)
size_t FSE_buildDTable_wksp(FSE_DTable *dt, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog, void *workspace, size_t workspaceSize)
{
void *const tdPtr = dt + 1; /* because *dt is unsigned, 32-bits aligned on 32-bits */
FSE_DECODE_TYPE *const tableDecode = (FSE_DECODE_TYPE *)(tdPtr);
U16 symbolNext[FSE_MAX_SYMBOL_VALUE + 1];
U16 *symbolNext = (U16 *)workspace;
U32 const maxSV1 = maxSymbolValue + 1;
U32 const tableSize = 1 << tableLog;
U32 highThreshold = tableSize - 1;
/* Sanity Checks */
if (workspaceSize < sizeof(U16) * (FSE_MAX_SYMBOL_VALUE + 1))
return ERROR(tableLog_tooLarge);
if (maxSymbolValue > FSE_MAX_SYMBOL_VALUE)
return ERROR(maxSymbolValue_tooLarge);
if (tableLog > FSE_MAX_TABLELOG)
@@ -288,16 +291,32 @@ size_t FSE_decompress_usingDTable(void *dst, size_t originalSize, const void *cS
return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 0);
}
size_t FSE_decompress_wksp(void *dst, size_t dstCapacity, const void *cSrc, size_t cSrcSize, FSE_DTable *workSpace, unsigned maxLog)
size_t FSE_decompress_wksp(void *dst, size_t dstCapacity, const void *cSrc, size_t cSrcSize, unsigned maxLog, void *workspace, size_t workspaceSize)
{
const BYTE *const istart = (const BYTE *)cSrc;
const BYTE *ip = istart;
short counting[FSE_MAX_SYMBOL_VALUE + 1];
unsigned tableLog;
unsigned maxSymbolValue = FSE_MAX_SYMBOL_VALUE;
size_t NCountLength;
FSE_DTable *dt;
short *counting;
size_t spaceUsed32 = 0;
FSE_STATIC_ASSERT(sizeof(FSE_DTable) == sizeof(U32));
dt = (FSE_DTable *)((U32 *)workspace + spaceUsed32);
spaceUsed32 += FSE_DTABLE_SIZE_U32(maxLog);
counting = (short *)((U32 *)workspace + spaceUsed32);
spaceUsed32 += ALIGN(sizeof(short) * (FSE_MAX_SYMBOL_VALUE + 1), sizeof(U32)) >> 2;
if ((spaceUsed32 << 2) > workspaceSize)
return ERROR(tableLog_tooLarge);
workspace = (U32 *)workspace + spaceUsed32;
workspaceSize -= (spaceUsed32 << 2);
/* normal FSE decoding mode */
size_t const NCountLength = FSE_readNCount(counting, &maxSymbolValue, &tableLog, istart, cSrcSize);
NCountLength = FSE_readNCount(counting, &maxSymbolValue, &tableLog, istart, cSrcSize);
if (FSE_isError(NCountLength))
return NCountLength;
// if (NCountLength >= cSrcSize) return ERROR(srcSize_wrong); /* too small input size; supposed to be already checked in NCountLength, only remaining
@@ -307,7 +326,7 @@ size_t FSE_decompress_wksp(void *dst, size_t dstCapacity, const void *cSrc, size
ip += NCountLength;
cSrcSize -= NCountLength;
CHECK_F(FSE_buildDTable(workSpace, counting, maxSymbolValue, tableLog));
CHECK_F(FSE_buildDTable_wksp(dt, counting, maxSymbolValue, tableLog, workspace, workspaceSize));
return FSE_decompress_usingDTable(dst, dstCapacity, ip, cSrcSize, workSpace); /* always return, even if it is an error code */
return FSE_decompress_usingDTable(dst, dstCapacity, ip, cSrcSize, dt); /* always return, even if it is an error code */
}