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Can TBB use concurrent_hash_map for another concurrent_hash_map?


Dear all,

I read the following example of concurrent_hash_map example( and this is fine:

    parallel_for( blocked_range<string*>( Data, Data+N, 1000 ),
                  Tally(table) );

Can the "Data" be a concurrent_hash_map type?

My requirement is that I have a concurrent_hash_map A, and a concurrent_hash_map B, how can I insert the entries in concurrent_hash_map A into the concurrent_hash_map B? I need to insert entries from concurrent_hash_maps into concurrent_hash_maps.

I write my code as follows:

 40 struct MyHashCompare {
 41   static size_t hash( const int& x ) {
 42     return x;
 43   }
 44   //! True if strings are equal
 45   static bool equal( const int& x, const int& y ) {
 46     return x==y;
 47   }
 48 };
 49 // A concurrent hash table that maps ints to ints.
 50 typedef concurrent_hash_map<int,int,MyHashCompare> mapTable;

 95 struct RULE{
 96   mapTable rule_index;
 97   mapTable word_index;
 98 };

105 struct RULE* rule_full;

295   rule_full=new struct RULE[rules];

112 struct count4Rule{
113   mapTable& table;
114   count4Rule( mapTable& table_ ) : table(table_) {}
115   void operator()( const blocked_range<int*> range ) const {
116 //
117   }
118 };

181       parallel_for(blocked_range< mapTable::iterator >(rule_full[rulenum].word_index.range(),64), count4Rule((rule_full[rulenum].word_index)));

However, when I compile the code, I get the following error:

icpc -g -O3 -std=c++11 -pthread -ltbb error: no instance of constructor "tbb::blocked_range<Value>::blocked_range [with Value=tbb::interface5::internal::hash_map_iterator<tbb::interface5::concurrent_hash_map<int, int, MyHashCompare, tbb::tbb_allocator<std::pair<int, int>>>, std::pair<const int, int>>]" matches the argument list
            argument types are: (tbb::interface5::internal::hash_map_range<tbb::interface5::internal::hash_map_iterator<tbb::interface5::concurrent_hash_map<int, int, MyHashCompare, tbb::tbb_allocator<std::pair<int, int>>>, std::pair<const int, int>>>)
        parallel_for(blocked_range< mapTable::iterator >(rule_full[rulenum].word_index.range()), count4Rule((rule_full[rulenum].word_index)));

compilation aborted for (code 2)
make: *** [main] Error 2

What should I do? Any suggestions or example?



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