mirror of https://github.com/YosysHQ/yosys.git
81 lines
1.6 KiB
Plaintext
81 lines
1.6 KiB
Plaintext
pattern reduce
|
|
|
|
state <IdString> portname
|
|
udata <vector<pair<Cell*, IdString>>> chain longest_chain
|
|
udata <pool<Cell*>> non_first_cells
|
|
|
|
code
|
|
non_first_cells.clear();
|
|
subpattern(setup);
|
|
endcode
|
|
|
|
match first
|
|
select first->type.in($_AND_, $_OR_, $_XOR_)
|
|
filter !non_first_cells.count(first)
|
|
endmatch
|
|
|
|
code
|
|
longest_chain.clear();
|
|
chain.push_back(make_pair(first, \A));
|
|
subpattern(tail);
|
|
chain.back().second = \B;
|
|
subpattern(tail);
|
|
finally
|
|
chain.pop_back();
|
|
log_assert(chain.empty());
|
|
accept;
|
|
endcode
|
|
|
|
// ------------------------------------------------------------------
|
|
|
|
subpattern setup
|
|
|
|
match first
|
|
select first->type.in($_AND_, $_OR_, $_XOR_)
|
|
endmatch
|
|
|
|
code portname
|
|
portname = \A;
|
|
branch;
|
|
portname = \B;
|
|
endcode
|
|
|
|
match next
|
|
select nusers(port(next, \Y)) == 2
|
|
select next->type.in($_AND_, $_OR_, $_XOR_)
|
|
index <IdString> next->type === first->type
|
|
index <SigSpec> port(next, \Y) === port(first, portname)
|
|
endmatch
|
|
|
|
code
|
|
non_first_cells.insert(next);
|
|
endcode
|
|
|
|
// ------------------------------------------------------------------
|
|
|
|
subpattern tail
|
|
arg first
|
|
|
|
match next
|
|
semioptional
|
|
select nusers(port(next, \Y)) == 2
|
|
select next->type.in($_AND_, $_OR_, $_XOR_)
|
|
index <IdString> next->type === chain.back().first->type
|
|
index <SigSpec> port(next, \Y) === port(chain.back().first, chain.back().second)
|
|
endmatch
|
|
|
|
code
|
|
if (next) {
|
|
chain.push_back(make_pair(next, \A));
|
|
subpattern(tail);
|
|
chain.back().second = \B;
|
|
subpattern(tail);
|
|
} else {
|
|
if (GetSize(chain) > GetSize(longest_chain))
|
|
longest_chain = chain;
|
|
}
|
|
finally
|
|
if (next)
|
|
chain.pop_back();
|
|
endcode
|