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Rough draft speed optimization

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This commit is contained in:
Danielle Rozenblit
2022-10-17 10:24:29 -07:00
parent 75cd42afd7
commit a08fabd51a
2 changed files with 28 additions and 4 deletions
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lib/common/huf.h
+1 -1
View File
@@ -173,7 +173,7 @@ size_t HUF_decompress4X2_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize,
/* ****************************************
* HUF detailed API
* ****************************************/
#define HUF_OPTIMAL_DEPTH_THRESHOLD ZSTD_btultra
#define HUF_OPTIMAL_DEPTH_THRESHOLD 3
typedef enum {
HUF_depth_fast, /** Use heuristic to find the table depth**/
HUF_depth_optimal /** Test possible table depths to find the one that produces the smallest header + encoded size**/
lib/compress/huf_compress.c
+27 -3
View File
@@ -1258,7 +1258,8 @@ unsigned HUF_minTableLog(size_t srcSize, unsigned symbolCardinality)
unsigned HUF_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue, void* workSpace, size_t wkspSize, HUF_CElt* table, const unsigned* count, HUF_depth_mode depthMode)
{
unsigned optLog = FSE_optimalTableLog_internal(maxTableLog, srcSize, maxSymbolValue, 1);
unsigned optLogGuess = FSE_optimalTableLog_internal(maxTableLog, srcSize, maxSymbolValue, 1);
unsigned optLog = optLogGuess;
if (depthMode == HUF_depth_optimal) { /** Test valid depths and return optimal **/
BYTE* dst = (BYTE*)workSpace + sizeof(HUF_WriteCTableWksp);
@@ -1267,10 +1268,11 @@ unsigned HUF_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxS
unsigned huffLog;
size_t maxBits, hSize, newSize;
const unsigned symbolCardinality = HUF_cardinality(count, maxSymbolValue);
const unsigned minTableLog = HUF_minTableLog(srcSize, symbolCardinality);
if (wkspSize < sizeof(HUF_buildCTable_wksp_tables)) return optLog;
for (huffLog = HUF_minTableLog(srcSize, symbolCardinality); huffLog <= maxTableLog; huffLog++) {
for (huffLog = optLogGuess; huffLog >= minTableLog; huffLog--) {
maxBits = HUF_buildCTable_wksp(table, count,
maxSymbolValue, huffLog,
workSpace, wkspSize);
@@ -1282,7 +1284,29 @@ unsigned HUF_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxS
newSize = HUF_estimateCompressedSize(table, count, maxSymbolValue) + hSize;
if (newSize < optSize) {
if (newSize > optSize) {
break;
} else {
optSize = newSize;
optLog = huffLog;
}
}
for (huffLog = optLogGuess + 1; huffLog <= maxTableLog; huffLog++) {
maxBits = HUF_buildCTable_wksp(table, count,
maxSymbolValue, huffLog,
workSpace, wkspSize);
if (ERR_isError(maxBits)) continue;
hSize = HUF_writeCTable_wksp(dst, dstSize, table, maxSymbolValue, (U32)maxBits,
workSpace, wkspSize);
if (ERR_isError(hSize)) continue;
newSize = HUF_estimateCompressedSize(table, count, maxSymbolValue) + hSize;
if (newSize > optSize) {
break;
} else {
optSize = newSize;
optLog = huffLog;
}