eden-emu/opus
18
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Use _BitScanReverse for EC_ILOG with MSVC.

Browse source 
Also updates the TI dsplib macros to use the same EC_CLZ mechanism
 as everything else.
This commit is contained in:
Timothy B. Terriberry 2010-12-23 08:06:48 -08:00 • committed by Jean-Marc Valin
parent 1aaa50d1c1
commit df2c71ea5a
1 changed files with 22 additions and 12 deletions
Download patch file Download diff file Expand all files Collapse all files

26
libcelt/ecintrin.h
View file

@ -83,16 +83,29 @@
/*Count leading zeros. /*Count leading zeros.
This macro should only be used for implementing ec_ilog(), if it is defined. This macro should only be used for implementing ec_ilog(), if it is defined.
All other code should use EC_ILOG() instead.*/ All other code should use EC_ILOG() instead.*/
#ifdef __GNUC_PREREQ #if defined(_MSC_VER)
#if __GNUC_PREREQ(3,4) # include <intrin.h>
static __inline int ec_bsr(unsigned long _x){
unsigned long ret;
_BitScanReverse(&ret,_x);
return (int)ret;
}
# define EC_CLZ0 (1)
# define EC_CLZ(_x) (-ec_bsr(_x))
#elif defined(ENABLE_TI_DSPLIB)
# include "dsplib.h"
# define EC_CLZ0 (31)
# define EC_CLZ(_x) (_lnorm(x))
#elif defined(__GNUC_PREREQ)
# if __GNUC_PREREQ(3,4)
# if INT_MAX>=2147483647 # if INT_MAX>=2147483647
# define EC_CLZ0 sizeof(unsigned)*CHAR_BIT # define EC_CLZ0 ((int)sizeof(unsigned)*CHAR_BIT)
# define EC_CLZ(_x) (__builtin_clz(_x)) # define EC_CLZ(_x) (__builtin_clz(_x))
# elif LONG_MAX>=2147483647L # elif LONG_MAX>=2147483647L
# define EC_CLZ0 sizeof(unsigned long)*CHAR_BIT # define EC_CLZ0 ((int)sizeof(unsigned long)*CHAR_BIT)
# define EC_CLZ(_x) (__builtin_clzl(_x)) # define EC_CLZ(_x) (__builtin_clzl(_x))
# endif # endif
#endif # endif
#endif #endif
#if defined(EC_CLZ) #if defined(EC_CLZ)
@ -101,9 +114,6 @@
The majority of the time we can never pass it zero. The majority of the time we can never pass it zero.
When we need to, it can be special cased.*/ When we need to, it can be special cased.*/
# define EC_ILOG(_x) (EC_CLZ0-EC_CLZ(_x)) # define EC_ILOG(_x) (EC_CLZ0-EC_CLZ(_x))
#elif defined(ENABLE_TI_DSPLIB)
#include "dsplib.h"
#define EC_ILOG(x) (31 - _lnorm(x))
#else #else
# define EC_ILOG(_x) (ec_ilog(_x)) # define EC_ILOG(_x) (ec_ilog(_x))
#endif #endif