Differences

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--- chess:programming:lsb_least_significant_bit [2021/10/30 12:05] – [Using de Bruijn] peter
+++ chess:programming:lsb_least_significant_bit [2021/10/30 13:11] (current) – peter
@@ Line 98: / Line 98: @@
 ----
-===== Using de Bruijn for 32-bit =====
-u32 msbDeBruijn32(u32 v)
-{
-    static const int MultiplyDeBruijnBitPosition[32] =
-    {
-, 9, 1, 10, 13, 21, 2, 29, 11, 14, 16, 18, 22, 25, 3, 30,
-, 12, 20, 28, 15, 17, 24, 7, 19, 27, 23, 6, 26, 5, 4, 31
-    };
-    v |= v >> 1; // first round down to one less than a power of 2
-    v |= v >> 2;
-    v |= v >> 4;
-    v |= v >> 8;
-    v |= v >> 16;
-    return MultiplyDeBruijnBitPosition[( u32 )( v * 0x07C4ACDDU ) >> 27];
-}
-</code>
-----
 ===== Using Logs =====
@@ Line 209: / Line 188: @@
 ===== References =====
-https://docs.microsoft.com/en-us/cpp/intrinsics/bitscanforward-bitscanforward64?redirectedfrom=MSDN&view=msvc-160
 http://graphics.stanford.edu/~seander/bithacks.html#IntegerLogDeBruijn
@@ Line 217: / Line 194: @@
 https://en.wikipedia.org/wiki/Bit_numbering
+https://docs.microsoft.com/en-us/cpp/intrinsics/bitscanforward-bitscanforward64?redirectedfrom=MSDN&view=msvc-160