--- a/macros.h Sat Jul 30 08:15:15 2005 +0000
+++ b/macros.h Sat Jul 30 09:29:20 2005 +0000
@@ -146,8 +146,10 @@
/// 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)