USING_YOSYS_NAMESPACE
PRIVATE_NAMESPACE_BEGIN
-void proc_rmdead(RTLIL::SwitchRule *sw, int &counter, int &full_case_counter)
+static bool can_use_fully_defined_pool(RTLIL::SwitchRule *sw)
+{
+ if (!GetSize(sw->signal))
+ return false;
+
+ for (const RTLIL::SigBit &bit : sw->signal)
+ if (bit.wire == NULL)
+ return false;
+
+ for (const RTLIL::CaseRule *cas : sw->cases)
+ for (const RTLIL::SigSpec &sig : cas->compare)
+ if (!sig.is_fully_def())
+ return false;
+
+ return true;
+}
+
+// This replicates the necessary parts of BitPatternPool's interface, but rather
+// than storing remaining patterns, this explicitly stores which fully-defined
+// constants have already been matched.
+struct FullyDefinedPool
+{
+ FullyDefinedPool(const RTLIL::SigSpec &signal)
+ : max_patterns{signal.size() >= 32 ? 0ul : 1ul << signal.size()}
+ {}
+
+ bool take(RTLIL::SigSpec sig)
+ {
+ if (default_reached || patterns.count(sig))
+ return false;
+ patterns.insert(sig);
+ return true;
+ }
+
+ void take_all()
+ {
+ default_reached = true;
+ }
+
+ bool empty()
+ {
+ return default_reached ||
+ (max_patterns && max_patterns == patterns.size());
+ }
+
+ pool<RTLIL::SigSpec> patterns;
+ bool default_reached = false;
+ size_t max_patterns;
+};
+
+void proc_rmdead(RTLIL::SwitchRule *sw, int &counter, int &full_case_counter);
+
+template <class Pool>
+static void proc_rmdead_impl(RTLIL::SwitchRule *sw, int &counter, int &full_case_counter)
{
- BitPatternPool pool(sw->signal);
+ Pool pool(sw->signal);
for (size_t i = 0; i < sw->cases.size(); i++)
{
}
}
+void proc_rmdead(RTLIL::SwitchRule *sw, int &counter, int &full_case_counter)
+{
+ if (can_use_fully_defined_pool(sw))
+ proc_rmdead_impl<FullyDefinedPool>(sw, counter, full_case_counter);
+ else
+ proc_rmdead_impl<BitPatternPool>(sw, counter, full_case_counter);
+}
+
struct ProcRmdeadPass : public Pass {
ProcRmdeadPass() : Pass("proc_rmdead", "eliminate dead trees in decision trees") { }
void help() override
projects / yosys.git / commitdiff