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Fixed a bug in opt_muxtree for "mux forests"

This commit is contained in:
Clifford Wolf 2015-01-17 13:56:53 +01:00
parent 3628ca989c
commit a95c229e12
1 changed files with 18 additions and 4 deletions
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22
passes/opt/opt_muxtree.cc
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@ -69,6 +69,8 @@ struct OptMuxtreeWorker
std::vector<muxinfo_t> mux2info;
std::set<int> root_muxes;
OptMuxtreeWorker(RTLIL::Design *design, RTLIL::Module *module) :
design(design), module(module), assign_map(module), removed_count(0)
{
@ -159,15 +161,26 @@ struct OptMuxtreeWorker
log(" Evaluating internal representation of mux trees.\n");
std::set<int> root_muxes;
dict<int, pool<int>> mux_to_users;
for (auto &bi : bit2info) {
for (int i : bi.mux_drivers)
for (int j : bi.mux_users)
mux_to_users[i].insert(j);
if (!bi.seen_non_mux)
continue;
for (int mux_idx : bi.mux_drivers)
root_muxes.insert(mux_idx);
}
for (int mux_idx : root_muxes)
for (auto &it : mux_to_users)
if (GetSize(it.second) > 1)
root_muxes.insert(it.first);
for (int mux_idx : root_muxes) {
log(" Root of a mux tree: %s\n", log_id(mux2info[mux_idx].cell));
eval_root_mux(mux_idx);
}
log(" Analyzing evaluation results.\n");
@ -317,7 +330,8 @@ struct OptMuxtreeWorker
parent_muxes.push_back(m);
}
for (int m : parent_muxes)
eval_mux(knowledge, m);
if (!root_muxes.count(m))
eval_mux(knowledge, m);
for (int m : parent_muxes)
knowledge.visited_muxes.erase(m);
@ -355,7 +369,7 @@ struct OptMuxtreeWorker
}
if (did_something) {
log(" Replacing known input bits on port %s of cell %s: %s -> %s\n", log_id(portname),
log(" Replacing known input bits on port %s of cell %s: %s -> %s\n", log_id(portname),
log_id(muxinfo.cell), log_signal(muxinfo.cell->getPort(portname)), log_signal(sig));
muxinfo.cell->setPort(portname, sig);
}