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removed huf_compress_impl.h

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re-imported all functions inside huf_compress.c
for easier source editing.

Also updated a bunch of code comments
for clarification.
This commit is contained in:
Yann Collet
2018-03-13 14:14:05 -07:00
parent facc09aa03
commit a95a88af57
7 changed files with 272 additions and 257 deletions
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lib/compress/fse_compress.c
+15 -7
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@@ -292,7 +292,7 @@ size_t FSE_writeNCount (void* buffer, size_t bufferSize, const short* normalized
It doesn't use any additional memory.
But this function is unsafe : it doesn't check that all values within `src` can fit into `count`.
For this reason, prefer using a table `count` with 256 elements.
@return : count of most numerous element
@return : count of most numerous element.
*/
size_t FSE_count_simple(unsigned* count, unsigned* maxSymbolValuePtr,
const void* src, size_t srcSize)
@@ -305,7 +305,10 @@ size_t FSE_count_simple(unsigned* count, unsigned* maxSymbolValuePtr,
memset(count, 0, (maxSymbolValue+1)*sizeof(*count));
if (srcSize==0) { *maxSymbolValuePtr = 0; return 0; }
while (ip<end) count[*ip++]++;
while (ip<end) {
assert(*ip <= maxSymbolValue);
count[*ip++]++;
}
while (!count[maxSymbolValue]) maxSymbolValue--;
*maxSymbolValuePtr = maxSymbolValue;
@@ -318,7 +321,8 @@ size_t FSE_count_simple(unsigned* count, unsigned* maxSymbolValuePtr,
/* FSE_count_parallel_wksp() :
* Same as FSE_count_parallel(), but using an externally provided scratch buffer.
* `workSpace` size must be a minimum of `1024 * sizeof(unsigned)`` */
* `workSpace` size must be a minimum of `1024 * sizeof(unsigned)`.
* @return : largest histogram frequency, or an error code (notably when histogram would be larger than *maxSymbolValuePtr). */
static size_t FSE_count_parallel_wksp(
unsigned* count, unsigned* maxSymbolValuePtr,
const void* source, size_t sourceSize,
@@ -333,7 +337,7 @@ static size_t FSE_count_parallel_wksp(
U32* const Counting3 = Counting2 + 256;
U32* const Counting4 = Counting3 + 256;
memset(Counting1, 0, 4*256*sizeof(unsigned));
memset(workSpace, 0, 4*256*sizeof(unsigned));
/* safety checks */
if (!sourceSize) {
@@ -379,7 +383,9 @@ static size_t FSE_count_parallel_wksp(
if (Counting1[s]) return ERROR(maxSymbolValue_tooSmall);
} }
{ U32 s; for (s=0; s<=maxSymbolValue; s++) {
{ U32 s;
if (maxSymbolValue > 255) maxSymbolValue = 255;
for (s=0; s<=maxSymbolValue; s++) {
count[s] = Counting1[s] + Counting2[s] + Counting3[s] + Counting4[s];
if (count[s] > max) max = count[s];
} }
@@ -393,9 +399,11 @@ static size_t FSE_count_parallel_wksp(
* Same as FSE_countFast(), but using an externally provided scratch buffer.
* `workSpace` size must be table of >= `1024` unsigned */
size_t FSE_countFast_wksp(unsigned* count, unsigned* maxSymbolValuePtr,
const void* source, size_t sourceSize, unsigned* workSpace)
const void* source, size_t sourceSize,
unsigned* workSpace)
{
if (sourceSize < 1500) return FSE_count_simple(count, maxSymbolValuePtr, source, sourceSize);
if (sourceSize < 1500) /* heuristic threshold */
return FSE_count_simple(count, maxSymbolValuePtr, source, sourceSize);
return FSE_count_parallel_wksp(count, maxSymbolValuePtr, source, sourceSize, 0, workSpace);
}