.

[SXSI/XMLTree.git] / libcds / src / basics.h

diff --git a/libcds/src/basics.h b/libcds/src/basics.h
index 39cb81b..3376902 100644 (file)
--- a/libcds/src/basics.h
+++ b/libcds/src/basics.h
@@ -41,25 +41,22 @@ using namespace std;
 #define mask31 0x0000001F
 
 /** max function */
-#define max(x,y) ((x)>(y)?(x):(y))
+//#define max(x,y) ((x)>(y)?(x):(y))
 /** min function */
-#define min(x,y) ((x)<(y)?(x):(y))
+//#define min(x,y) ((x)<(y)?(x):(y))
 
 
 /** number of bits in a uint */
-#ifndef W
+#undef W
 #define W 32
-#endif
 
 /** W-1 */
-#ifndef Wminusone
+#undef Wminusone
 #define Wminusone 31
-#endif
 
 /** 2W*/
-#ifndef WW
+#undef WW
 #define WW 64
-#endif
 
 /** number of bits per uchar */
 #define bitsM 8
@@ -236,6 +233,20 @@ inline uint popcount(int x){
   return __popcount_tab[(x >>  0) & 0xff]  + __popcount_tab[(x >>  8) & 0xff]
           + __popcount_tab[(x >> 16) & 0xff] + __popcount_tab[(x >> 24) & 0xff];
 }
+inline unsigned int
+fast_popcount(int x)
+{
+    uint m1 = 0x55555555;
+    uint m2 = 0x33333333;
+    uint m4 = 0x0f0f0f0f;
+    x -= (x >> 1) & m1;
+    x = (x & m2) + ((x >> 2) & m2);
+    x = (x + (x >> 4)) & m4;
+    x += x >>  8;
+    return (x + (x >> 16)) & 0x3f;
+}
+
+
 
 /** Counts the number of 1s in the first 16 bits of x */
 inline uint popcount16(int x){