diff options
Diffstat (limited to 'passes/opt/wreduce.cc')
| -rw-r--r-- | passes/opt/wreduce.cc | 31 |
1 files changed, 27 insertions, 4 deletions
diff --git a/passes/opt/wreduce.cc b/passes/opt/wreduce.cc index 1fbc41082..908a85d5b 100644 --- a/passes/opt/wreduce.cc +++ b/passes/opt/wreduce.cc @@ -342,9 +342,9 @@ struct WreduceWorker } } - if (cell->type.in("$pos", "$add", "$mul", "$and", "$or", "$xor")) + if (cell->type.in("$pos", "$add", "$mul", "$and", "$or", "$xor", "$sub")) { - bool is_signed = cell->getParam("\\A_SIGNED").as_bool(); + bool is_signed = cell->getParam("\\A_SIGNED").as_bool() || cell->type == "$sub"; int a_size = 0, b_size = 0; if (cell->hasPort("\\A")) a_size = GetSize(cell->getPort("\\A")); @@ -352,7 +352,7 @@ struct WreduceWorker int max_y_size = max(a_size, b_size); - if (cell->type == "$add") + if (cell->type.in("$add", "$sub")) max_y_size++; if (cell->type == "$mul") @@ -365,6 +365,29 @@ struct WreduceWorker } } + if (cell->type.in("$add", "$sub")) { + SigSpec A = mi.sigmap(cell->getPort("\\A")); + SigSpec B = mi.sigmap(cell->getPort("\\B")); + bool sub = cell->type == "$sub"; + + int i; + for (i = 0; i < GetSize(sig); i++) { + if (B.at(i, Sx) != S0 && (sub || A.at(i, Sx) != S0)) + break; + if (B[i] == S0) + module->connect(sig[i], A[i]); + else if (A[i] == S0) + module->connect(sig[i], B[i]); + else log_abort(); + } + if (i > 0) { + cell->setPort("\\A", A.extract(i, -1)); + cell->setPort("\\B", B.extract(i, -1)); + sig.remove(0, i); + bits_removed += i; + } + } + if (GetSize(sig) == 0) { log("Removed cell %s.%s (%s).\n", log_id(module), log_id(cell), log_id(cell->type)); module->remove(cell); @@ -372,7 +395,7 @@ struct WreduceWorker } if (bits_removed) { - log("Removed top %d bits (of %d) from port Y of cell %s.%s (%s).\n", + log("Removed %d bits (of %d) from port Y of cell %s.%s (%s).\n", bits_removed, GetSize(sig) + bits_removed, log_id(module), log_id(cell), log_id(cell->type)); cell->setPort("\\Y", sig); did_something = true; |