Make mph_bits compile fast.

cxxmph/mph_bits.cc

@@ -8,28 +8,4 @@ dynamic_2bitset::dynamic_2bitset(uint32_t size, bool fill)
     : size_(size), fill_(fill), data_(ceil(size / 4.0), ones()*fill) {}
 dynamic_2bitset::~dynamic_2bitset() {}
 
-template <int n, int mask = (1 << 7)> struct bitcount {
-enum { value = (n & mask ? 1:0) + bitcount<n, (mask >> 1)>::value };
-};
-template <int n> struct bitcount<n, 0> { enum { value = 0 }; };
-
-template <int size, int index = size>
-class CompileTimeRankTable {
-public:
-CompileTimeRankTable() : current(bitcount<index - 1>::value) { }
-uint8_t operator[] (uint8_t i) { return *(&current + size - i - 1); }
-private:
-unsigned char current;
-CompileTimeRankTable<index -1> next;
-};
-template <int size> class CompileTimeRankTable<size, 0> { };
-static CompileTimeRankTable<256> kRanktable;
-
-uint8_t Ranktable::get(uint8_t i) { return kRanktable[i]; }
-
-void stop_unused_warning() {
-  rank64(4);
-  nextpoweroftwo(4);
-}
-
 }

cxxmph/mph_bits.h

@@ -68,13 +68,6 @@ static uint32_t nextpoweroftwo(uint32_t k) {
 // rank and select:
 // http://vigna.dsi.unimi.it/ftp/papers/Broadword.pdf
 
-struct Ranktable { static uint8_t get(uint8_t); };
-static uint8_t rank64(uint64_t bits) {
-  auto bytes = reinterpret_cast<const uint8_t*>(&bits);
-  return Ranktable::get(bytes[0]) + Ranktable::get(bytes[1]) +
-         Ranktable::get(bytes[2]) + Ranktable::get(bytes[3]);
-};
-  
 }  // namespace cxxmph
 
 #endif

cxxmph/mph_bits_test.cc

@@ -4,7 +4,6 @@
 #include "mph_bits.h"
 
 using cxxmph::dynamic_2bitset;
-using cxxmph::rank64;
 using cxxmph::nextpoweroftwo;
 
 int main(int argc, char** argv) {
@@ -57,11 +56,6 @@ int main(int argc, char** argv) {
   empty.swap(large);
 
   if (nextpoweroftwo(3) != 4) exit(-1);
-  
-  if (rank64(0) != 0) exit(-1);
-  if (rank64(1) != 1) exit(-1);
-  if (rank64(2) != 1) exit(-1);
-  if (rank64(255) != 8) exit(-1);
 }
   
   

cxxmph/mph_map.h

@@ -21,9 +21,10 @@
 #include <vector>
 #include <utility>  // for std::pair
 
+#include "hollow_iterator.h"
 #include "mph_bits.h"
 #include "mph_index.h"
-#include "hollow_iterator.h"
+#include "seeded_hash.h"
 
 namespace cxxmph {