luke
/
abc
mirror of https://github.com/YosysHQ/abc.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Adding local search for covering

This commit is contained in:
aletempiac 2023-11-15 21:57:29 +01:00
parent c07080f818
commit dcc960beba
1 changed files with 48 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

48
src/acd/ac_decomposition.hpp
View File

@ -1079,6 +1079,9 @@ private:
return;
}
/* improve solution with local search */
covering_improve( matrix, solution );
/* compute best bound sets */
uint32_t num_luts = 1 + solution[4];
uint32_t num_levels = 2;
@ -1526,6 +1529,51 @@ private:
return res;
}
bool covering_improve( std::vector<encoding_matrix>& matrix, std::array<uint32_t, 5>& solution )
{
/* performs one iteration of local search */
uint32_t best_cost = 0, local_cost = 0;
uint32_t num_elements = solution[4];
uint32_t combinations = ( best_multiplicity * ( best_multiplicity - 1 ) ) / 2;
bool improved = false;
/* compute current cost */
for ( uint32_t i = 0; i < num_elements; ++i )
{
best_cost += matrix[solution[i]].cost;
}
uint64_t column;
for ( uint32_t i = 0; i < num_elements; ++i )
{
/* remove element i */
local_cost = 0;
column = 0;
for ( uint32_t j = 0; j < num_elements; ++j )
{
if ( j == i )
continue;
local_cost += matrix[solution[j]].cost;
column |= matrix[solution[j]].column;
}
/* search for a better replecemnts */
for ( uint32_t j = 0; j < matrix.size(); ++j )
{
if ( __builtin_popcount( column | matrix[j].column ) != combinations )
continue;
if ( local_cost + matrix[j].cost < best_cost )
{
solution[i] = j;
best_cost = local_cost + matrix[j].cost;
improved = true;
}
}
}
return improved;
}
void adjust_truth_table_on_dc( STT& tt, STT& care, uint32_t var_index )
{
assert( var_index < tt.num_vars() );