reduced table sizes for HUF_readDTableX4

diff --git a/lib/common/entropy_common.c b/lib/common/entropy_common.c
index 8a31c4696de287a71fa3acf5eff6b196400ecfb6..83fd971546b3786eef4c51af6a96d52eb42280fa 100644 (file)
--- a/lib/common/entropy_common.c
+++ b/lib/common/entropy_common.c
@@ -159,6 +159,7 @@ size_t FSE_readNCount (short* normalizedCounter, unsigned* maxSVPtr, unsigned* t
 /*! HUF_readStats() :
     Read compact Huffman tree, saved by HUF_writeCTable().
     `huffWeight` is destination buffer.
+    `rankStats` is assumed to be a table of at least HUF_TABLELOG_MAX U32.
     @return : size read from `src` , or an error Code .
     Note : Needed by HUF_readCTable() and HUF_readDTableX?() .
 */
@@ -187,17 +188,17 @@ size_t HUF_readStats(BYTE* huffWeight, size_t hwSize, U32* rankStats,
                 huffWeight[n+1] = ip[n/2] & 15;
     }   }   }
     else  {   /* header compressed with FSE (normal case) */
-        FSE_DTable fseWorkspace[FSE_DTABLE_SIZE_U32(5)];  /* 5 is max possible tableLog for HUF header */
+        FSE_DTable fseWorkspace[FSE_DTABLE_SIZE_U32(6)];  /* 6 is max possible tableLog for HUF header (maybe even 5, to be tested) */
         if (iSize+1 > srcSize) return ERROR(srcSize_wrong);
-        oSize = FSE_decompress_wksp(huffWeight, hwSize-1, ip+1, iSize, fseWorkspace, 5);   /* max (hwSize-1) values decoded, as last one is implied */
+        oSize = FSE_decompress_wksp(huffWeight, hwSize-1, ip+1, iSize, fseWorkspace, 6);   /* max (hwSize-1) values decoded, as last one is implied */
         if (FSE_isError(oSize)) return oSize;
     }
 
     /* collect weight stats */
-    memset(rankStats, 0, (HUF_TABLELOG_ABSOLUTEMAX + 1) * sizeof(U32));
+    memset(rankStats, 0, (HUF_TABLELOG_MAX + 1) * sizeof(U32));
     weightTotal = 0;
     {   U32 n; for (n=0; n<oSize; n++) {
-            if (huffWeight[n] >= HUF_TABLELOG_ABSOLUTEMAX) return ERROR(corruption_detected);
+            if (huffWeight[n] >= HUF_TABLELOG_MAX) return ERROR(corruption_detected);
             rankStats[huffWeight[n]]++;
             weightTotal += (1 << huffWeight[n]) >> 1;
     }   }
@@ -205,7 +206,7 @@ size_t HUF_readStats(BYTE* huffWeight, size_t hwSize, U32* rankStats,
 
     /* get last non-null symbol weight (implied, total must be 2^n) */
     {   U32 const tableLog = BIT_highbit32(weightTotal) + 1;
-        if (tableLog > HUF_TABLELOG_ABSOLUTEMAX) return ERROR(corruption_detected);
+        if (tableLog > HUF_TABLELOG_MAX) return ERROR(corruption_detected);
         *tableLogPtr = tableLog;
         /* determine last weight */
         {   U32 const total = 1 << tableLog;

diff --git a/lib/common/huf.h b/lib/common/huf.h
index 5087d36a20c8630a87732ddc6fe9182715f11438..35d6033ea9676fdd84bed306db67ec7f1f0d54ce 100644 (file)
--- a/lib/common/huf.h
+++ b/lib/common/huf.h
@@ -62,19 +62,19 @@ size_t HUF_compress(void* dst, size_t dstCapacity,
 HUF_decompress() :
     Decompress HUF data from buffer 'cSrc', of size 'cSrcSize',
     into already allocated buffer 'dst', of minimum size 'dstSize'.
-    `dstSize` : **must** be the ***exact*** size of original (uncompressed) data.
+    `originalSize` : **must** be the ***exact*** size of original (uncompressed) data.
     Note : in contrast with FSE, HUF_decompress can regenerate
            RLE (cSrcSize==1) and uncompressed (cSrcSize==dstSize) data,
            because it knows size to regenerate.
-    @return : size of regenerated data (== dstSize),
+    @return : size of regenerated data (== originalSize),
               or an error code, which can be tested using HUF_isError()
 */
-size_t HUF_decompress(void* dst,  size_t dstSize,
+size_t HUF_decompress(void* dst,  size_t originalSize,
                 const void* cSrc, size_t cSrcSize);
 
 
 /* ***   Tool functions *** */
-#define HUF_BLOCKSIZE_MAX (128 * 1024)
+#define HUF_BLOCKSIZE_MAX (128 * 1024)       /*< maximum input size for a single block compressed with HUF_compress */
 size_t HUF_compressBound(size_t size);       /**< maximum compressed size (worst case) */
 
 /* Error Management */
@@ -85,7 +85,8 @@ const char* HUF_getErrorName(size_t code);   /**< provides error code string (us
 /* ***   Advanced function   *** */
 
 /** HUF_compress2() :
-*   Same as HUF_compress(), but offers direct control over `maxSymbolValue` and `tableLog` */
+ *   Same as HUF_compress(), but offers direct control over `maxSymbolValue` and `tableLog` .
+ *   `tableLog` must be `<= HUF_TABLELOG_MAX` . */
 size_t HUF_compress2 (void* dst, size_t dstSize, const void* src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog);
 
 /** HUF_compress4X_wksp() :
@@ -101,7 +102,7 @@ size_t HUF_compress4X_wksp (void* dst, size_t dstSize, const void* src, size_t s
 
 
 /* *** Constants *** */
-#define HUF_TABLELOG_ABSOLUTEMAX  16   /* absolute limit of HUF_MAX_TABLELOG. Beyond that value, code does not work */
+#define HUF_TABLELOG_ABSOLUTEMAX  15   /* absolute limit of HUF_MAX_TABLELOG. Beyond that value, code does not work */
 #define HUF_TABLELOG_MAX  12           /* max configured tableLog (for static allocation); can be modified up to HUF_ABSOLUTEMAX_TABLELOG */
 #define HUF_TABLELOG_DEFAULT  11       /* tableLog by default, when not specified */
 #define HUF_SYMBOLVALUE_MAX 255
@@ -128,9 +129,9 @@ size_t HUF_compress4X_wksp (void* dst, size_t dstSize, const void* src, size_t s
 typedef U32 HUF_DTable;
 #define HUF_DTABLE_SIZE(maxTableLog)   (1 + (1<<(maxTableLog)))
 #define HUF_CREATE_STATIC_DTABLEX2(DTable, maxTableLog) \
-        HUF_DTable DTable[HUF_DTABLE_SIZE((maxTableLog)-1)] = { ((U32)((maxTableLog)-1)*0x1000001) }
+        HUF_DTable DTable[HUF_DTABLE_SIZE((maxTableLog)-1)] = { ((U32)((maxTableLog)-1) * 0x01000001) }
 #define HUF_CREATE_STATIC_DTABLEX4(DTable, maxTableLog) \
-        HUF_DTable DTable[HUF_DTABLE_SIZE(maxTableLog)] = { ((U32)(maxTableLog)*0x1000001) }
+        HUF_DTable DTable[HUF_DTABLE_SIZE(maxTableLog)] = { ((U32)(maxTableLog) * 0x01000001) }
 
 
 /* ****************************************

diff --git a/lib/decompress/huf_decompress.c b/lib/decompress/huf_decompress.c
index e94fa83ccd7d230732f9ceebd8e853a9450fd707..d212dd88e1a6fcd885924ad8dead24584229c5ff 100644 (file)
--- a/lib/decompress/huf_decompress.c
+++ b/lib/decompress/huf_decompress.c
@@ -398,14 +398,14 @@ static void HUF_fillDTableX4Level2(HUF_DEltX4* DTable, U32 sizeLog, const U32 co
     }   }
 }
 
-typedef U32 rankVal_t[HUF_TABLELOG_ABSOLUTEMAX][HUF_TABLELOG_ABSOLUTEMAX + 1];
+typedef U32 rankVal_t[HUF_TABLELOG_MAX][HUF_TABLELOG_MAX + 1];
 
 static void HUF_fillDTableX4(HUF_DEltX4* DTable, const U32 targetLog,
                            const sortedSymbol_t* sortedList, const U32 sortedListSize,
                            const U32* rankStart, rankVal_t rankValOrigin, const U32 maxWeight,
                            const U32 nbBitsBaseline)
 {
-    U32 rankVal[HUF_TABLELOG_ABSOLUTEMAX + 1];
+    U32 rankVal[HUF_TABLELOG_MAX + 1];
     const int scaleLog = nbBitsBaseline - targetLog;   /* note : targetLog >= srcLog, hence scaleLog <= 1 */
     const U32 minBits  = nbBitsBaseline - maxWeight;
     U32 s;
@@ -446,8 +446,8 @@ size_t HUF_readDTableX4 (HUF_DTable* DTable, const void* src, size_t srcSize)
 {
     BYTE weightList[HUF_SYMBOLVALUE_MAX + 1];
     sortedSymbol_t sortedSymbol[HUF_SYMBOLVALUE_MAX + 1];
-    U32 rankStats[HUF_TABLELOG_ABSOLUTEMAX + 1] = { 0 };
-    U32 rankStart0[HUF_TABLELOG_ABSOLUTEMAX + 2] = { 0 };
+    U32 rankStats[HUF_TABLELOG_MAX + 1] = { 0 };
+    U32 rankStart0[HUF_TABLELOG_MAX + 2] = { 0 };
     U32* const rankStart = rankStart0+1;
     rankVal_t rankVal;
     U32 tableLog, maxW, sizeOfSort, nbSymbols;
@@ -458,7 +458,7 @@ size_t HUF_readDTableX4 (HUF_DTable* DTable, const void* src, size_t srcSize)
     HUF_DEltX4* const dt = (HUF_DEltX4*)dtPtr;
 
     HUF_STATIC_ASSERT(sizeof(HUF_DEltX4) == sizeof(HUF_DTable));   /* if compilation fails here, assertion is false */
-    if (maxTableLog > HUF_TABLELOG_ABSOLUTEMAX) return ERROR(tableLog_tooLarge);
+    if (maxTableLog > HUF_TABLELOG_MAX) return ERROR(tableLog_tooLarge);
     /* memset(weightList, 0, sizeof(weightList)); */  /* is not necessary, even though some analyzer complain ... */
 
     iSize = HUF_readStats(weightList, HUF_SYMBOLVALUE_MAX + 1, rankStats, &nbSymbols, &tableLog, src, srcSize);