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(svn r19789) -Add [FS#3519]: a typed FOR_EACH_SET_BIT (adf88)

release/1.1
rubidium 2010-05-11 20:59:54 +00:00
parent be504a6ef0
commit 2c25f51281
1 changed files with 28 additions and 6 deletions
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34
src/core/bitmath_func.hpp
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@ -306,6 +306,31 @@ static FORCEINLINE T ROR(const T x, const uint8 n)
return (T)(x >> n | x << (sizeof(x) * 8 - n));
}
/**
* Do an operation for each set bit in a value.
*
* This macros is used to do an operation for each set
* bit in a variable. The second parameter is a
* variable that is used as the bit position counter.
* The fourth parameter is an expression of the bits
* we need to iterate over. This expression will be
* evaluated once.
*
* @param Tbitpos_type Type of the position counter variable.
* @param bitpos_var The position counter variable.
* @param Tbitset_type Type of the bitset value.
* @param bitset_value The bitset value which we check for bits.
*
* @see FOR_EACH_SET_BIT
*/
#define FOR_EACH_SET_BIT_EX(Tbitpos_type, bitpos_var, Tbitset_type, bitset_value) \
for ( \
Tbitset_type ___FESBE_bits = (bitpos_var = (Tbitpos_type)0, bitset_value); \
___FESBE_bits != (Tbitset_type)0; \
___FESBE_bits = (Tbitset_type)(___FESBE_bits >> 1), bitpos_var++ \
) \
if ((___FESBE_bits & 1) != 0)
/**
* Do an operation for each set set bit in a value.
*
@ -316,13 +341,10 @@ static FORCEINLINE T ROR(const T x, const uint8 n)
* we need to iterate over. This expression will be
* evaluated once.
*
* @param i The position counter
* @param b The value which we check for set bits
* @param bitpos_var The position counter variable.
* @param bitset_value The value which we check for set bits.
*/
#define FOR_EACH_SET_BIT(i, b) \
for (uint __FESB_bits = (i = 0, b); __FESB_bits != 0; i++, __FESB_bits >>= 1) \
if (__FESB_bits & 1)
#define FOR_EACH_SET_BIT(bitpos_var, bitset_value) FOR_EACH_SET_BIT_EX(uint, bitpos_var, uint, bitset_value)
#if defined(__APPLE__)
/* Make endian swapping use Apple's macros to increase speed