Merge pull request #288 from apache/cpc_check_pseudo_phase

check pseudo phase

Author: AlexanderSaydakov

cpc/include/cpc_compressor_impl.hpp

@@ -297,6 +297,7 @@ void cpc_compressor<A>::compress_sliding_flavor(const cpc_sketch_alloc<A>& sourc
     // changes the implied ordering of the pairs, so we must do it before sorting.
 
     const uint8_t pseudo_phase = determine_pseudo_phase(source.get_lg_k(), source.get_num_coupons());
+    if (pseudo_phase >= 16) throw std::logic_error("unexpected pseudo phase for sliding flavor");
     const uint8_t* permutation = column_permutations_for_encoding[pseudo_phase];
 
     const uint8_t offset = source.window_offset;
@@ -333,7 +334,7 @@ void cpc_compressor<A>::uncompress_sliding_flavor(const compressed_state<A>& sou
         lg_k, source.table_data.get_allocator());
 
     const uint8_t pseudo_phase = determine_pseudo_phase(lg_k, num_coupons);
-    if (pseudo_phase >= 16) throw std::logic_error("pseudo phase >= 16");
+    if (pseudo_phase >= 16) throw std::logic_error("unexpected pseudo phase for sliding flavor");
     const uint8_t* permutation = column_permutations_for_decoding[pseudo_phase];
 
     uint8_t offset = cpc_sketch_alloc<A>::determine_correct_offset(lg_k, num_coupons);