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opt_lut to ignore LUT cells, or those that drive bits, with (* keep *)

This commit is contained in:
Eddie Hung 2019-08-07 13:12:28 -07:00
parent 3414ee1e3f
commit f69410daaf
1 changed files with 6 additions and 0 deletions
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6
passes/opt/opt_lut.cc
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@ -101,6 +101,12 @@ struct OptLutWorker
{ {
if (cell->type == "$lut") if (cell->type == "$lut")
{ {
if (cell->has_keep_attr())
continue;
SigBit lut_output = cell->getPort("\\Y");
if (lut_output.wire->get_bool_attribute("\\keep"))
continue;
int lut_width = cell->getParam("\\WIDTH").as_int(); int lut_width = cell->getParam("\\WIDTH").as_int();
SigSpec lut_input = cell->getPort("\\A"); SigSpec lut_input = cell->getPort("\\A");
int lut_arity = 0; int lut_arity = 0;