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fix confusion between unsigned <-> U32

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as suggested in #1441.

generally U32 and unsigned are the same thing,
except when they are not ...

case : 32-bit compilation for MIPS (uint32_t == unsigned long)

A vast majority of transformation consists in transforming U32 into unsigned.
In rare cases, it's the other way around (typically for internal code, such as seeds).

Among a few issues this patches solves :
- some parameters were declared with type `unsigned` in *.h,
  but with type `U32` in their implementation *.c .
- some parameters have type unsigned*,
  but the caller user a pointer to U32 instead.

These fixes are useful.

However, the bulk of changes is about %u formating,
which requires unsigned type,
but generally receives U32 values instead,
often just for brevity (U32 is shorter than unsigned).
These changes are generally minor, or even annoying.

As a consequence, the amount of code changed is larger than I would expect for such a patch.

Testing is also a pain :
it requires manually modifying `mem.h`,
in order to lie about `U32`
and force it to be an `unsigned long` typically.
On a 64-bit system, this will break the equivalence unsigned == U32.
Unfortunately, it will also break a few static_assert(), controlling structure sizes.
So it also requires modifying `debug.h` to make `static_assert()` a noop.
And then reverting these changes.

So it's inconvenient, and as a consequence,
this property is currently not checked during CI tests.
Therefore, these problems can emerge again in the future.

I wonder if it is worth ensuring proper distinction of U32 != unsigned in CI tests.
It's another restriction for coding, adding more frustration during merge tests,
since most platforms don't need this distinction (hence contributor will not see it),
and while this can matter in theory, the number of platforms impacted seems minimal.

Thoughts ?
This commit is contained in:
Yann Collet
2018-12-21 18:09:41 -08:00
parent 8f35c7f94c
commit ededcfca57
30 changed files with 401 additions and 388 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lib/compress/huf_compress.c
+12 -11
View File
@@ -88,13 +88,13 @@ static size_t HUF_compressWeights (void* dst, size_t dstSize, const void* weight
BYTE* op = ostart;
BYTE* const oend = ostart + dstSize;
U32 maxSymbolValue = HUF_TABLELOG_MAX;
unsigned maxSymbolValue = HUF_TABLELOG_MAX;
U32 tableLog = MAX_FSE_TABLELOG_FOR_HUFF_HEADER;
FSE_CTable CTable[FSE_CTABLE_SIZE_U32(MAX_FSE_TABLELOG_FOR_HUFF_HEADER, HUF_TABLELOG_MAX)];
BYTE scratchBuffer[1<<MAX_FSE_TABLELOG_FOR_HUFF_HEADER];
U32 count[HUF_TABLELOG_MAX+1];
unsigned count[HUF_TABLELOG_MAX+1];
S16 norm[HUF_TABLELOG_MAX+1];
/* init conditions */
@@ -134,7 +134,7 @@ struct HUF_CElt_s {
`CTable` : Huffman tree to save, using huf representation.
@return : size of saved CTable */
size_t HUF_writeCTable (void* dst, size_t maxDstSize,
const HUF_CElt* CTable, U32 maxSymbolValue, U32 huffLog)
const HUF_CElt* CTable, unsigned maxSymbolValue, unsigned huffLog)
{
BYTE bitsToWeight[HUF_TABLELOG_MAX + 1]; /* precomputed conversion table */
BYTE huffWeight[HUF_SYMBOLVALUE_MAX];
@@ -169,7 +169,7 @@ size_t HUF_writeCTable (void* dst, size_t maxDstSize,
}
size_t HUF_readCTable (HUF_CElt* CTable, U32* maxSymbolValuePtr, const void* src, size_t srcSize)
size_t HUF_readCTable (HUF_CElt* CTable, unsigned* maxSymbolValuePtr, const void* src, size_t srcSize)
{
BYTE huffWeight[HUF_SYMBOLVALUE_MAX + 1]; /* init not required, even though some static analyzer may complain */
U32 rankVal[HUF_TABLELOG_ABSOLUTEMAX + 1]; /* large enough for values from 0 to 16 */
@@ -315,7 +315,7 @@ typedef struct {
U32 current;
} rankPos;
static void HUF_sort(nodeElt* huffNode, const U32* count, U32 maxSymbolValue)
static void HUF_sort(nodeElt* huffNode, const unsigned* count, U32 maxSymbolValue)
{
rankPos rank[32];
U32 n;
@@ -347,7 +347,7 @@ static void HUF_sort(nodeElt* huffNode, const U32* count, U32 maxSymbolValue)
*/
#define STARTNODE (HUF_SYMBOLVALUE_MAX+1)
typedef nodeElt huffNodeTable[HUF_CTABLE_WORKSPACE_SIZE_U32];
size_t HUF_buildCTable_wksp (HUF_CElt* tree, const U32* count, U32 maxSymbolValue, U32 maxNbBits, void* workSpace, size_t wkspSize)
size_t HUF_buildCTable_wksp (HUF_CElt* tree, const unsigned* count, U32 maxSymbolValue, U32 maxNbBits, void* workSpace, size_t wkspSize)
{
nodeElt* const huffNode0 = (nodeElt*)workSpace;
nodeElt* const huffNode = huffNode0+1;
@@ -421,7 +421,7 @@ size_t HUF_buildCTable_wksp (HUF_CElt* tree, const U32* count, U32 maxSymbolValu
* @return : maxNbBits
* Note : count is used before tree is written, so they can safely overlap
*/
size_t HUF_buildCTable (HUF_CElt* tree, const U32* count, U32 maxSymbolValue, U32 maxNbBits)
size_t HUF_buildCTable (HUF_CElt* tree, const unsigned* count, unsigned maxSymbolValue, unsigned maxNbBits)
{
huffNodeTable nodeTable;
return HUF_buildCTable_wksp(tree, count, maxSymbolValue, maxNbBits, nodeTable, sizeof(nodeTable));
@@ -629,7 +629,7 @@ static size_t HUF_compressCTable_internal(
}
typedef struct {
U32 count[HUF_SYMBOLVALUE_MAX + 1];
unsigned count[HUF_SYMBOLVALUE_MAX + 1];
HUF_CElt CTable[HUF_SYMBOLVALUE_MAX + 1];
huffNodeTable nodeTable;
} HUF_compress_tables_t;
@@ -689,9 +689,10 @@ HUF_compress_internal (void* dst, size_t dstSize,
/* Build Huffman Tree */
huffLog = HUF_optimalTableLog(huffLog, srcSize, maxSymbolValue);
{ CHECK_V_F(maxBits, HUF_buildCTable_wksp(table->CTable, table->count,
maxSymbolValue, huffLog,
table->nodeTable, sizeof(table->nodeTable)) );
{ size_t const maxBits = HUF_buildCTable_wksp(table->CTable, table->count,
maxSymbolValue, huffLog,
table->nodeTable, sizeof(table->nodeTable));
CHECK_F(maxBits);
huffLog = (U32)maxBits;
/* Zero unused symbols in CTable, so we can check it for validity */
memset(table->CTable + (maxSymbolValue + 1), 0,