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author | tron <tron@openttd.org> | 2005-07-30 09:29:20 +0000 |
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committer | tron <tron@openttd.org> | 2005-07-30 09:29:20 +0000 |
commit | 9b676d2cd992726223c39fd46db97994685df13f (patch) | |
tree | 4e9f7fae006fcf7f0433f1e421bad805c1c2013f /macros.h | |
parent | 79620db9be3e0cf8e773558ccd8b0fa399fe90d7 (diff) | |
download | openttd-9b676d2cd992726223c39fd46db97994685df13f.tar.xz |
(svn r2758) Add the AB() macro to add a value to a bit range and use it in a few places, also make use of GB and SB nearby
Diffstat (limited to 'macros.h')
-rw-r--r-- | macros.h | 4 |
1 files changed, 3 insertions, 1 deletions
@@ -146,8 +146,10 @@ static inline void swap_tile(TileIndex *a, TileIndex *b) { TileIndex t = *a; *a /// Fetch n bits starting at bit s from x #define GB(x, s, n) (((x) >> (s)) & ((1 << (n)) - 1)) -/// Set n bits in x starting at bit s to d +/// Set n bits starting at bit s in x to d #define SB(x, s, n, d) ((x) = ((x) & ~(((1 << (n)) - 1) << (s))) | ((d) << (s))) +/// Add i to the n bits starting at bit s in x +#define AB(x, s, n, i) ((x) = ((x) & ~(((1 << (n)) - 1) << (s))) | (((x) + ((i) << (s))) & (((1 << (n)) - 1) << (s)))) /** * ROtate x Left/Right by n (must be >= 0) |