rapidus liberty latch D->Q/EN->Q matching

Signed-off-by: James Cherry <cherry@parallaxsw.com>

include/sta/TimingArc.hh

@@ -176,6 +176,7 @@ public:
   // other conditional timing arcs between the same pins.
   bool isCondDefault() const { return is_cond_default_; }
   void setIsCondDefault(bool is_default);
+  const FuncExpr *when() const { return attrs_->cond(); }
   // SDF IOPATHs match sdfCond.
   // sdfCond (IOPATH) reuses sdfCondStart (timing check) variable.
   const std::string &sdfCond() const { return attrs_->sdfCondStart(); }

liberty/Liberty.cc

@@ -1679,22 +1679,30 @@ LibertyCell::makeLatchEnables(Report *report,
 {
   if (hasSequentials()
       || hasInferedRegTimingArcs()) {
-    for (auto en_to_q : timing_arc_sets_) {
+    for (TimingArcSet *d_to_q : timing_arc_sets_) {
-      if (en_to_q->role() == TimingRole::latchEnToQ()) {
+      if (d_to_q->role() == TimingRole::latchDtoQ()) {
-        LibertyPort *en = en_to_q->from();
-        LibertyPort *q = en_to_q->to();
-        for (TimingArcSet *d_to_q : timingArcSetsTo(q)) {
-          if (d_to_q->role() == TimingRole::latchDtoQ()
-              && condMatch(en_to_q, d_to_q)) {
         LibertyPort *d = d_to_q->from();
+        LibertyPort *q = d_to_q->to();
+        TimingArcSet *en_to_q = nullptr;
+        TimingArcSet *en_to_q_when = nullptr;
+        // Prefer en_to_q with matching when.
+        for (TimingArcSet *arc_to_q : timingArcSetsTo(q)) {
+          if (arc_to_q->role() == TimingRole::latchEnToQ()) {
+            if (condMatch(arc_to_q, d_to_q))
+              en_to_q_when = arc_to_q;
+            else
+              en_to_q = arc_to_q;
+          }
+        }
+        if (en_to_q_when)
+          en_to_q = en_to_q_when;
+        if (en_to_q) {
+          LibertyPort *en = en_to_q->from();
           const RiseFall *en_rf = en_to_q->isRisingFallingEdge();
           if (en_rf) {
-              TimingArcSet *setup_check = findLatchSetup(d, en, en_rf, q, d_to_q,
+            TimingArcSet *setup_check = findLatchSetup(d, en, en_rf, q, d_to_q, report);
-                                                         report);
             LatchEnable *latch_enable = makeLatchEnable(d, en, en_rf, q, d_to_q,
-                                                          en_to_q,
+                                                        en_to_q, setup_check, debug);
-                                                          setup_check,
-                                                          debug);
             FuncExpr *en_func = latch_enable->enableFunc();
             if (en_func) {
               TimingSense en_sense = en_func->portTimingSense(en);
@@ -1717,7 +1725,12 @@ LibertyCell::makeLatchEnables(Report *report,
             }
           }
         }
-        }
+        else
+          report->warn(1121, "cell %s/%s no latch enable found for %s -> %s.",
+                       library_->name(),
+                       name(),
+                       d->name(),
+                       q->name());
       }
     }
   }
@@ -1810,8 +1823,7 @@ LibertyCell::makeLatchEnable(LibertyPort *d,
                              Debug *debug)
 {
   FuncExpr *en_func = findLatchEnableFunc(d, en, en_rf);
-  latch_enables_.emplace_back(d, en, en_rf, en_func, q, d_to_q, en_to_q,
+  latch_enables_.emplace_back(d, en, en_rf, en_func, q, d_to_q, en_to_q, setup_check);
-                              setup_check);
   size_t idx = latch_enables_.size() - 1;
   latch_d_to_q_map_[d_to_q] = idx;
   latch_check_map_[setup_check] = idx;

liberty/Liberty.i

@@ -379,6 +379,16 @@ full_name()
                         to);
 }
 
+const std::string
+when()
+{
+  const FuncExpr *when = self->when();
+  if (when)
+    return when->to_string();
+  else
+    return "";
+}
+
 TimingArcSeq &
 timing_arcs() { return self->arcs(); }
 

liberty/Liberty.tcl

@@ -126,7 +126,15 @@ proc report_timing_arcs { cell } {
     puts ""
     puts "Timing arcs"
     foreach timing_arc $timing_arcs {
-      puts [$timing_arc to_string]
+      puts " [$timing_arc to_string]"
+      puts "  [$timing_arc role]"
+      set when [$timing_arc when]
+      if { $when != "" } {
+        puts "  when $when"
+      }
+      foreach arc [$timing_arc timing_arcs] {
+        puts "  [$arc from_edge] -> [$arc to_edge]"
+      }
     }
   }
 }

liberty/LibertyReader.cc

@@ -2115,6 +2115,7 @@ LibertyReader::makeTableModels(LibertyCell *cell,
                                const LibertyGroup *timing_group,
                                TimingArcAttrsPtr timing_attrs)
 {
+  bool found_model = false;
   for (const RiseFall *rf : RiseFall::range()) {
     std::string delay_attr_name  = "cell_" + rf->to_string_long();
     TableModel *delay = readGateTableModel(timing_group, delay_attr_name.c_str(), rf,
@@ -2160,8 +2161,9 @@ LibertyReader::makeTableModels(LibertyCell *cell,
         if (delay == nullptr)
           libWarn(1211, timing_group, "missing cell_%s.", rf->name());
       }
+      found_model = true;
     }
-
+    else {
       std::string constraint_attr_name  = rf->to_string_long() + "_constraint";
       ScaleFactorType scale_factor_type = 
         timingTypeScaleFactorType(timing_attrs->timingType());
@@ -2180,9 +2182,14 @@ LibertyReader::makeTableModels(LibertyCell *cell,
                                    ScaleFactorType::unknown);
         timing_attrs->setModel(rf, new CheckTableModel(cell, constraint,
                                                        std::move(constraint_sigmas)));
+        found_model = true;
       }
     }
   }
+  if (!found_model)
+    libWarn(1311, timing_group, "no table models found in timing group.");
+}
+
 
 bool
 LibertyReader::isGateTimingType(TimingType timing_type)

liberty/TimingArc.cc

@@ -207,7 +207,6 @@ TimingArcSet::to_string()
   std::string str = from_->name();
   str += " -> ";
   str += to_->name();
-  str += " " + role()->to_string();
   return str;
 }
 
@@ -333,7 +332,7 @@ TimingArcSet::isRisingFallingEdge() const
     if (from_rf1 == from_rf2)
       return from_rf1;
   }
-  if (arcs_.size() == 1)
+  if (arc_count == 1)
     return arcs_[0]->fromEdge()->asRiseFall();
   else
     return nullptr;