more accurate gain function

diff --git a/lib/zstd_opt.h b/lib/zstd_opt.h
index 5bb40e607fd37035443085f26102b79df9b77e58..55acef67fe5ae6fc96d74a5c16b8d0da9db51f65 100644 (file)
--- a/lib/zstd_opt.h
+++ b/lib/zstd_opt.h
@@ -37,26 +37,26 @@
 FORCE_INLINE U32 ZSTD_GETPRICE(seqStore_t* seqStorePtr, U32 litLength, const BYTE* literals, U32 offset, U32 matchLength)
 {
     /* offset */
-    BYTE offCode = offset ? (BYTE)ZSTD_highbit(offset) + 1 : 0;
-    U32 price = offCode + ZSTD_highbit(seqStorePtr->offCodeSum) - ZSTD_highbit(seqStorePtr->offCodeFreq[offCode]);
+    BYTE offCode = offset ? (BYTE)ZSTD_highbit(offset+1) + 1 : 0;
+    U32 price = (offCode-1) + (!offCode) + ZSTD_highbit(seqStorePtr->offCodeSum+1) - ZSTD_highbit(seqStorePtr->offCodeFreq[offCode]+1);
 
     /* match Length */
     matchLength -= MINMATCHOPT;
     price += ((matchLength >= MaxML)<<3) + ((matchLength >= 255+MaxML)<<4) + ((matchLength>=(1<<15))<<3);
     if (matchLength >= MaxML) matchLength = MaxML;
-    price += ZSTD_getLiteralPrice(seqStorePtr, litLength, literals) + ZSTD_highbit(seqStorePtr->matchLengthSum) - ZSTD_highbit(seqStorePtr->matchLengthFreq[matchLength]);
+    price += ZSTD_getLiteralPrice(seqStorePtr, litLength, literals) + ZSTD_highbit(seqStorePtr->matchLengthSum+1) - ZSTD_highbit(seqStorePtr->matchLengthFreq[matchLength]+1);
 
     switch (seqStorePtr->priceFunc)
     {
-        default:   
+        default:
         case 0:
-            return price + seqStorePtr->factor + ((seqStorePtr->litSum>>5) / seqStorePtr->litLengthSum) + ((seqStorePtr->litSum<<1) / (seqStorePtr->litSum + seqStorePtr->matchSum));
+            return 1 + price + seqStorePtr->factor + ((seqStorePtr->litSum>>5) / seqStorePtr->litLengthSum) + ((seqStorePtr->litSum<<1) / (seqStorePtr->litSum + seqStorePtr->matchSum));
         case 1:
-            return price + seqStorePtr->factor + ((seqStorePtr->factor2) ? ((seqStorePtr->litSum>>5) / seqStorePtr->litLengthSum) + ((seqStorePtr->litSum<<1) / (seqStorePtr->litSum + seqStorePtr->matchSum)) : 0);
+            return 1 + price + seqStorePtr->factor + ((seqStorePtr->factor2) ? ((seqStorePtr->litSum>>5) / seqStorePtr->litLengthSum) + ((seqStorePtr->litSum<<1) / (seqStorePtr->litSum + seqStorePtr->matchSum)) : 0);
         case 2:
-            return price + seqStorePtr->factor + ((seqStorePtr->factor2) ? ((seqStorePtr->litSum>>4) / seqStorePtr->litLengthSum) + ((seqStorePtr->litSum<<1) / (seqStorePtr->litSum + seqStorePtr->matchSum)) : 0);
+            return 1 + price + seqStorePtr->factor + ((seqStorePtr->factor2) ? ((seqStorePtr->litSum>>4) / seqStorePtr->litLengthSum) + ((seqStorePtr->litSum<<1) / (seqStorePtr->litSum + seqStorePtr->matchSum)) : 0);
         case 3:
-            return price;
+            return 1 + price;
     }
 }
 

diff --git a/lib/zstd_opt_internal.h b/lib/zstd_opt_internal.h
index 8628875299bb957a862835298b9d4783ad5cd4ad..a40cad068cc823281cca5d4de9cb409efb210619 100644 (file)
--- a/lib/zstd_opt_internal.h
+++ b/lib/zstd_opt_internal.h
@@ -52,7 +52,7 @@
     #define ZSTD_LOG_TRY_PRICE(...) printf(__VA_ARGS__)
 #else
     #define ZSTD_LOG_PARSER(...)
-    #define ZSTD_LOG_ENCODE(...)
+    #define ZSTD_LOG_ENCODE(...) // printf(__VA_ARGS__)
     #define ZSTD_LOG_TRY_PRICE(...)
 #endif
 
@@ -136,7 +136,7 @@ MEM_STATIC void ZSTD_updatePrice(seqStore_t* seqStorePtr, U32 litLength, const B
 
     /* match offset */
     seqStorePtr->offCodeSum += ZSTD_FREQ_STEP;
-    BYTE offCode = offset ? (BYTE)ZSTD_highbit(offset) + 1 : 0;
+    BYTE offCode = offset ? (BYTE)ZSTD_highbit(offset+1) + 1 : 0;
     seqStorePtr->offCodeFreq[offCode] += ZSTD_FREQ_STEP;
 
     /* match Length */
@@ -152,17 +152,17 @@ FORCE_INLINE U32 ZSTD_getLiteralPrice(seqStore_t* seqStorePtr, U32 litLength, co
     U32 price, u;
 
     if (litLength == 0)
-        return ZSTD_highbit(seqStorePtr->litLengthSum) - ZSTD_highbit(seqStorePtr->litLengthFreq[0]);
+        return ZSTD_highbit(seqStorePtr->litLengthSum+1) - ZSTD_highbit(seqStorePtr->litLengthFreq[0]+1);
 
     /* literals */
-    price = litLength * ZSTD_highbit(seqStorePtr->litSum);
+    price = litLength * ZSTD_highbit(seqStorePtr->litSum+1);
     for (u=0; u < litLength; u++)
-        price -= ZSTD_highbit(seqStorePtr->litFreq[literals[u]]);
+        price -= ZSTD_highbit(seqStorePtr->litFreq[literals[u]]+1);
 
     /* literal Length */
     price += ((litLength >= MaxLL)<<3) + ((litLength >= 255+MaxLL)<<4) + ((litLength>=(1<<15))<<3);
     if (litLength >= MaxLL) litLength = MaxLL;
-    price += ZSTD_highbit(seqStorePtr->litLengthSum) - ZSTD_highbit(seqStorePtr->litLengthFreq[litLength]);
+    price += ZSTD_highbit(seqStorePtr->litLengthSum+1) - ZSTD_highbit(seqStorePtr->litLengthFreq[litLength]+1);
 
     return price;
 }