kannonier8/blender
1
0
Fork 0
forked from bartvdbraak/blender
Code Pull Requests Activity

BLI_mempool: Use an 'odd' FREEWORD for big/little endian

Browse Source 
This also changes freeword to an intptr_t to ensure
not only the first 4 bits of a pointer are tested on 64bit systems.
This commit is contained in:
Campbell Barton 2016-06-01 02:52:05 +10:00
parent d2bb0e660b
commit aedeca7d1c
1 changed files with 19 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
source/blender/blenlib/intern/BLI_mempool.c
View File

@ -57,12 +57,29 @@
#ifdef __BIG_ENDIAN__
/* Big Endian */
# define MAKE_ID(a, b, c, d) ( (int)(a) << 24 | (int)(b) << 16 | (c) << 8 | (d) )
# define MAKE_ID_8(a, b, c, d, e, f, g, h) \
((int64_t)(a) << 56 | (int64_t)(b) << 48 | (int64_t)(c) << 40 | (int64_t)(d) << 32 | \
(int64_t)(e) << 24 | (int64_t)(f) << 16 | (int64_t)(g) << 8 | (h) )
#else
/* Little Endian */
# define MAKE_ID(a, b, c, d) ( (int)(d) << 24 | (int)(c) << 16 | (b) << 8 | (a) )
# define MAKE_ID_8(a, b, c, d, e, f, g, h) \
((int64_t)(h) << 56 | (int64_t)(g) << 48 | (int64_t)(f) << 40 | (int64_t)(e) << 32 | \
(int64_t)(d) << 24 | (int64_t)(c) << 16 | (int64_t)(b) << 8 | (a) )
#endif
#define FREEWORD MAKE_ID('f', 'r', 'e', 'e')
/**
* Important that this value is an is _not_ aligned with ``sizeof(void *)``.
* So having a pointer to 2/4/8... aligned memory is enough to ensure the freeword will never be used.
* To be safe, use a word thats the same in both directions.
*/
#define FREEWORD ((sizeof(void *) > sizeof(int32_t)) ? \
MAKE_ID_8('e', 'e', 'r', 'f', 'f', 'r', 'e', 'e') : \
MAKE_ID('e', 'f', 'f', 'e'))
/**
* The 'used' word just needs to be set to something besides FREEWORD.
*/
#define USEDWORD MAKE_ID('u', 's', 'e', 'd')
/* currently totalloc isnt used */
@ -87,7 +104,7 @@ static bool mempool_debug_memset = false;
*/
typedef struct BLI_freenode {
struct BLI_freenode *next;
int freeword; /* used to identify this as a freed node */
intptr_t freeword; /* used to identify this as a freed node */
} BLI_freenode;
/**