diff options
author | rubidium <rubidium@openttd.org> | 2010-05-11 20:59:54 +0000 |
---|---|---|
committer | rubidium <rubidium@openttd.org> | 2010-05-11 20:59:54 +0000 |
commit | 2c25f512813b0871c62f209bc7303823edde886e (patch) | |
tree | 9f9fca063afedaed65f6b4d0a3ba6f3152e2c3a9 /src/core | |
parent | be504a6ef0f26b78216699d6995ccc8dee02a5c1 (diff) | |
download | openttd-2c25f512813b0871c62f209bc7303823edde886e.tar.xz |
(svn r19789) -Add [FS#3519]: a typed FOR_EACH_SET_BIT (adf88)
Diffstat (limited to 'src/core')
-rw-r--r-- | src/core/bitmath_func.hpp | 34 |
1 files changed, 28 insertions, 6 deletions
diff --git a/src/core/bitmath_func.hpp b/src/core/bitmath_func.hpp index a6b2ae446..14e9ed4e4 100644 --- a/src/core/bitmath_func.hpp +++ b/src/core/bitmath_func.hpp @@ -307,6 +307,31 @@ static FORCEINLINE T ROR(const T x, const uint8 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. * * This macros is used to do an operation for each set @@ -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 |