shared const BIT_mask

diff --git a/lib/bitstream.h b/lib/bitstream.h
index f2ed51bc5ab0a6c4ae8cc676ae6be3e19f6292da..62d2cb2bad6f80257de570e63f52f5adaaa70646 100644 (file)
--- a/lib/bitstream.h
+++ b/lib/bitstream.h
@@ -141,7 +141,7 @@ MEM_STATIC size_t BIT_readBitsFast(BIT_DStream_t* bitD, unsigned nbBits);
 
 
 /*-**************************************************************
-*  Helper functions
+*  Internal functions
 ****************************************************************/
 MEM_STATIC unsigned BIT_highbit32 (register U32 val)
 {
@@ -165,6 +165,9 @@ MEM_STATIC unsigned BIT_highbit32 (register U32 val)
 #   endif
 }
 
+/*=====    Local Constants   =====*/
+static const unsigned BIT_mask[] = { 0, 1, 3, 7, 0xF, 0x1F, 0x3F, 0x7F, 0xFF, 0x1FF, 0x3FF, 0x7FF, 0xFFF, 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF, 0x1FFFF, 0x3FFFF, 0x7FFFF, 0xFFFFF, 0x1FFFFF, 0x3FFFFF, 0x7FFFFF,  0xFFFFFF, 0x1FFFFFF, 0x3FFFFFF };   /* up to 26 bits */
+
 
 /*-**************************************************************
 *  bitStream encoding
@@ -189,8 +192,7 @@ MEM_STATIC size_t BIT_initCStream(BIT_CStream_t* bitC, void* startPtr, size_t ds
     Does not check for register overflow ! */
 MEM_STATIC void BIT_addBits(BIT_CStream_t* bitC, size_t value, unsigned nbBits)
 {
-    static const unsigned mask[] = { 0, 1, 3, 7, 0xF, 0x1F, 0x3F, 0x7F, 0xFF, 0x1FF, 0x3FF, 0x7FF, 0xFFF, 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF, 0x1FFFF, 0x3FFFF, 0x7FFFF, 0xFFFFF, 0x1FFFFF, 0x3FFFFF, 0x7FFFFF,  0xFFFFFF, 0x1FFFFFF, 0x3FFFFFF };   /* up to 26 bits */
-    bitC->bitContainer |= (value & mask[nbBits]) << bitC->bitPos;
+    bitC->bitContainer |= (value & BIT_mask[nbBits]) << bitC->bitPos;
     bitC->bitPos += nbBits;
 }
 
@@ -290,18 +292,14 @@ MEM_STATIC size_t BIT_getUpperBits(size_t bitD, U32 const start)
     return bitD >> start;
 }
 
-MEM_STATIC size_t BIT_getNBits(size_t bitD, U32 const nbBits, U32 const start)
+MEM_STATIC size_t BIT_getMiddleBits(size_t bitD, U32 const nbBits, U32 const start)
 {
-    static const unsigned mask[] = { 0, 1, 3, 7, 0xF, 0x1F, 0x3F, 0x7F, 0xFF, 0x1FF, 0x3FF, 0x7FF, 0xFFF, 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF, 0x1FFFF, 0x3FFFF, 0x7FFFF, 0xFFFFF, 0x1FFFFF, 0x3FFFFF, 0x7FFFFF,  0xFFFFFF, 0x1FFFFFF, 0x3FFFFFF };   /* up to 26 bits */
-    return (bitD >> start) & mask[nbBits];
+    return (bitD >> start) & BIT_mask[nbBits];
 }
 
-MEM_STATIC size_t BIT_consumeFirstBits(size_t* bitDPtr, U32 const nbBits)
+MEM_STATIC size_t BIT_getLowerBits(size_t bitD, U32 const nbBits)
 {
-    static const unsigned mask[] = { 0, 1, 3, 7, 0xF, 0x1F, 0x3F, 0x7F, 0xFF, 0x1FF, 0x3FF, 0x7FF, 0xFFF, 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF, 0x1FFFF, 0x3FFFF, 0x7FFFF, 0xFFFFF, 0x1FFFFF, 0x3FFFFF, 0x7FFFFF,  0xFFFFFF, 0x1FFFFFF, 0x3FFFFFF };   /* up to 26 bits */
-    size_t const result = *bitDPtr & mask[nbBits];
-    *bitDPtr >>= nbBits;
-    return result;
+    return bitD & BIT_mask[nbBits];
 }
 
 /*! BIT_lookBits() :

diff --git a/lib/zstd_decompress.c b/lib/zstd_decompress.c
index 3abd6bbc51f8dee0eff8fac3ac5553b4848733e0..7749ffd363a35c38073091c7771ae83298c11b71 100644 (file)
--- a/lib/zstd_decompress.c
+++ b/lib/zstd_decompress.c
@@ -655,8 +655,8 @@ static void ZSTD_decodeSequence(seq_t* seq, seqState_t* seqState, const U32 mls)
                 0x800000, 0x1000000, 0x2000000, 0x4000000, /*fake*/ 1, 1, 1, 1 };
 
     /* sequence */
-    seq->litLength = LL_base[llCode] + BIT_getNBits(allBits, llBits, 0);
-    seq->matchLength = ML_base[mlCode] + BIT_getNBits(allBits, mlBits, llBits) + mls;
+    seq->litLength = LL_base[llCode] + BIT_getLowerBits(allBits, llBits);
+    seq->matchLength = ML_base[mlCode] + mls + BIT_getMiddleBits(allBits, mlBits, llBits);
     {   size_t const offset = ofCode ? OF_base[ofCode] + BIT_getUpperBits(allBits, llBits+mlBits) :
                                        llCode ? seq->offset : seqState->prevOffset;
         if (ofCode | !llCode) seqState->prevOffset = seq->offset;   /* cmove */