Add getConflictingPipWire() arch API, router1 improvements

Signed-off-by: Clifford Wolf <clifford@clifford.at>

common/router1.cc

@@ -100,6 +100,7 @@ struct Router1
 
     std::unordered_map<WireId, int> wireScores;
     std::unordered_map<PipId, int> pipScores;
+    std::unordered_map<NetInfo*, int> netScores;
 
     int arcs_with_ripup = 0;
     int arcs_without_ripup = 0;
@@ -146,21 +147,23 @@ struct Router1
         if (ctx->debug)
             log("      ripup net %s\n", net->name.c_str(ctx));
 
+        netScores[net]++;
+
         auto net_wires_copy = net->wires;
         for (auto &it : net_wires_copy) {
             if (it.second.pip == PipId())
-                ripup_wire(it.first, true);
+                ripup_wire(it.first, 4);
             else
-                ripup_pip(it.second.pip, true);
+                ripup_pip(it.second.pip, 4);
         }
 
         ripup_flag = true;
     }
 
-    void ripup_wire(WireId wire, bool extra_indent = false)
+    void ripup_wire(WireId wire, int extra_indent = 0)
     {
         if (ctx->debug)
-            log("    %sripup wire %s\n", extra_indent ? "    " : "", ctx->getWireName(wire).c_str(ctx));
+            log("    %*sripup wire %s\n", extra_indent, "", ctx->getWireName(wire).c_str(ctx));
 
         wireScores[wire]++;
 
@@ -182,14 +185,13 @@ struct Router1
         ripup_flag = true;
     }
 
-    void ripup_pip(PipId pip, bool extra_indent = false)
+    void ripup_pip(PipId pip, int extra_indent = 0)
     {
         WireId wire = ctx->getPipDstWire(pip);
 
         if (ctx->debug)
-            log("    %sripup pip %s (%s)\n", extra_indent ? "    " : "", ctx->getPipName(pip).c_str(ctx), ctx->getWireName(wire).c_str(ctx));
+            log("    %*sripup pip %s (%s)\n", extra_indent, "", ctx->getPipName(pip).c_str(ctx), ctx->getWireName(wire).c_str(ctx));
 
-        wireScores[wire]++;
         pipScores[pip]++;
 
         if (ctx->getBoundPipNet(pip)) {
@@ -204,6 +206,7 @@ struct Router1
 
         if (0) {
 remove_wire_arcs:
+            wireScores[wire]++;
             for (auto &it : wire_to_arcs[wire]) {
                 arc_to_wires[it].erase(wire);
                 arc_queue_insert(it);
@@ -213,9 +216,11 @@ remove_wire_arcs:
 
         NetInfo *net = ctx->getConflictingPipNet(pip);
         if (net != nullptr) {
-            wireScores[wire] += net->wires.size();
+            wire = ctx->getConflictingPipWire(pip);
-            pipScores[pip] += net->wires.size();
+            if (wire != WireId())
-            ripup_net(net);
+                ripup_wire(wire, 2);
+            else
+                ripup_net(net);
         }
 
         ripup_flag = true;
@@ -436,11 +441,11 @@ remove_wire_arcs:
                         if (!ripup)
                             continue;
 
+                        next_penalty += cfg.wireRipupPenalty;
+
                         auto scores_it = wireScores.find(next_wire);
                         if (scores_it != wireScores.end())
                             next_penalty += scores_it->second * cfg.wireRipupPenalty;
-                        else
-                            next_penalty += cfg.wireRipupPenalty;
                     }
                 }
 
@@ -451,16 +456,29 @@ remove_wire_arcs:
                         continue;
 
                     if (ripupPipNet == net_info) {
+                        auto net_info_wire_it = net_info->wires.find(next_wire);
+                        if (net_info_wire_it == net_info->wires.end() || net_info_wire_it->second.pip != pip)
+                            goto pip_self_ripup;
                         next_bonus += cfg.pipReuseBonus;
                     } else {
+pip_self_ripup:
                         if (!ripup)
                             continue;
 
-                        auto scores_it = pipScores.find(pip);
+                        next_penalty += cfg.pipRipupPenalty;
-                        if (scores_it != pipScores.end())
+
-                            next_penalty += scores_it->second * cfg.pipRipupPenalty;
+                        auto pip_scores_it = pipScores.find(pip);
-                        else
+                        if (pip_scores_it != pipScores.end())
-                            next_penalty += cfg.pipRipupPenalty;
+                            next_penalty += pip_scores_it->second * cfg.pipRipupPenalty;
+
+                        if (ctx->getConflictingPipWire(pip) == WireId()) {
+                            auto net_scores_it = netScores.find(ripupPipNet);
+                            if (net_scores_it != netScores.end())
+                                next_penalty += net_scores_it->second * cfg.netRipupPenalty;
+
+                            next_penalty += ripupPipNet->wires.size() * cfg.wireRipupPenalty;
+                            next_penalty += (ripupPipNet->wires.size()-1) * cfg.pipRipupPenalty;
+                        }
                     }
                 }
 
@@ -479,9 +497,6 @@ remove_wire_arcs:
                     if (next_score + ctx->getDelayEpsilon() >= old_score)
                         continue;
 
-                    if (next_delay + ctx->getDelayEpsilon() >= old_delay)
-                        continue;
-
 #if 0
                     if (ctx->debug)
                         log("Found better route to %s. Old vs new delay estimate: %.3f (%.3f) %.3f (%.3f)\n",
@@ -538,6 +553,12 @@ remove_wire_arcs:
             return false;
         }
 
+        if (ctx->debug) {
+            log("  final route delay:   %8.2f\n", ctx->getDelayNS(visited[dst_wire].delay));
+            log("  final route penalty: %8.2f\n", ctx->getDelayNS(visited[dst_wire].penalty));
+            log("  final route bonus:   %8.2f\n", ctx->getDelayNS(visited[dst_wire].bonus));
+        }
+
         // bind resulting route (and maybe unroute other nets)
 
         std::unordered_set<WireId> unassign_wires = arc_to_wires[arc];
@@ -615,6 +636,7 @@ Router1Cfg::Router1Cfg(Context *ctx) : Settings(ctx)
 
     wireRipupPenalty = ctx->getRipupDelayPenalty();
     pipRipupPenalty = ctx->getRipupDelayPenalty();
+    netRipupPenalty = ctx->getRipupDelayPenalty();
 
     wireReuseBonus = wireRipupPenalty/8;
     pipReuseBonus = pipRipupPenalty/8;

common/router1.h

@@ -35,6 +35,7 @@ struct Router1Cfg : Settings
     bool useEstimate;
     delay_t wireRipupPenalty;
     delay_t pipRipupPenalty;
+    delay_t netRipupPenalty;
     delay_t wireReuseBonus;
     delay_t pipReuseBonus;
     delay_t estimatePrecision;

docs/archapi.md

@@ -217,12 +217,12 @@ Return the net a wire is bound to.
 
 ### NetInfo \*getConflictingWireNet(WireId wire) const
 
-If this returns a non-nullptr, then unbinding that net
+If this returns a non-nullptr, then unbinding the wire from that net
 will make the given wire available.
 
 This returns nullptr if the wire is already available,
-or if there is no single net that can be unbound to make this
+or if there is no net that can be unbound from the wire to make it
-wire available.
+available.
 
 ### DelayInfo getWireDelay(WireId wire) const
 
@@ -289,11 +289,21 @@ Return the net this pip is bound to.
 ### NetInfo \*getConflictingPipNet(PipId pip) const
 
 Return the net that needs to be unbound in order to make this
-pip available.
+pip available. Note that it may be neccessary to unroute that
+entire net to make the pip available.
 
-This does not need to (but may) return the conflicting wire if the conflict is
+This returns nullptr if the pip is already available,
-limited to the conflicting wire being bound to the destination wire for this
+or if there is no single net that can be unrouted to make
-pip.
+the pip available.
+
+### WireId getConflictingPipWire(PipId pip) const
+
+Return the single wire that needs to be unbound in order to make this pip
+available.
+
+This returns WireId() if the pip is already available,
+or if there is no single wire that can be unbound to make
+the pip available.
 
 ### const\_range\<PipId\> getPips() const
 

ecp5/arch.h

@@ -733,6 +733,11 @@ struct Arch : BaseCtx
             return pip_to_net.at(pip);
     }
 
+    WireId getConflictingPipWire(PipId pip) const
+    {
+        return WireId();
+    }
+
     AllPipRange getPips() const
     {
         AllPipRange range;

generic/arch.cc

@@ -373,6 +373,8 @@ NetInfo *Arch::getBoundPipNet(PipId pip) const { return pips.at(pip).bound_net;
 
 NetInfo *Arch::getConflictingPipNet(PipId pip) const { return pips.at(pip).bound_net; }
 
+WireId Arch::getConflictingPipWire(PipId pip) const { return pips.at(pip).bound_net ? pips.at(pip).dstWire : WireId(); }
+
 const std::vector<PipId> &Arch::getPips() const { return pip_ids; }
 
 Loc Arch::getPipLocation(PipId pip) const { return pips.at(pip).loc; }

generic/arch.h

@@ -187,6 +187,7 @@ struct Arch : BaseCtx
     bool checkPipAvail(PipId pip) const;
     NetInfo *getBoundPipNet(PipId pip) const;
     NetInfo *getConflictingPipNet(PipId pip) const;
+    WireId getConflictingPipWire(PipId pip) const;
     const std::vector<PipId> &getPips() const;
     Loc getPipLocation(PipId pip) const;
     WireId getPipSrcWire(PipId pip) const;

gui/designwidget.cc

@@ -515,6 +515,8 @@ void DesignWidget::onSelectionChanged(const QItemSelection &, const QItemSelecti
         addProperty(topItem, QVariant::String, "Bound Net", ctx->nameOf(ctx->getBoundPipNet(pip)), ElementType::NET);
         addProperty(topItem, QVariant::String, "Conflicting Net", ctx->nameOf(ctx->getConflictingPipNet(pip)),
                     ElementType::NET);
+        addProperty(topItem, QVariant::String, "Conflicting Wire", ctx->getWireName(ctx->getConflictingPipWire(pip)).c_str(ctx),
+                    ElementType::WIRE);
         addProperty(topItem, QVariant::String, "Src Wire", ctx->getWireName(ctx->getPipSrcWire(pip)).c_str(ctx),
                     ElementType::WIRE);
         addProperty(topItem, QVariant::String, "Dest Wire", ctx->getWireName(ctx->getPipDstWire(pip)).c_str(ctx),

ice40/arch.h

@@ -404,7 +404,7 @@ struct Arch : BaseCtx
     std::vector<CellInfo *> bel_to_cell;
     std::vector<NetInfo *> wire_to_net;
     std::vector<NetInfo *> pip_to_net;
-    std::vector<NetInfo *> switches_locked;
+    std::vector<WireId> switches_locked;
 
     ArchArgs args;
     Arch(ArchArgs args);
@@ -546,7 +546,7 @@ struct Arch : BaseCtx
         auto pip = it->second.pip;
         if (pip != PipId()) {
             pip_to_net[pip.index] = nullptr;
-            switches_locked[chip_info->pip_data[pip.index].switch_index] = nullptr;
+            switches_locked[chip_info->pip_data[pip.index].switch_index] = WireId();
         }
 
         net_wires.erase(it);
@@ -608,14 +608,15 @@ struct Arch : BaseCtx
     {
         NPNR_ASSERT(pip != PipId());
         NPNR_ASSERT(pip_to_net[pip.index] == nullptr);
-        NPNR_ASSERT(switches_locked[chip_info->pip_data[pip.index].switch_index] == nullptr);
+        NPNR_ASSERT(switches_locked[chip_info->pip_data[pip.index].switch_index] == WireId());
-
-        pip_to_net[pip.index] = net;
-        switches_locked[chip_info->pip_data[pip.index].switch_index] = net;
 
         WireId dst;
         dst.index = chip_info->pip_data[pip.index].dst;
         NPNR_ASSERT(wire_to_net[dst.index] == nullptr);
+
+        pip_to_net[pip.index] = net;
+        switches_locked[chip_info->pip_data[pip.index].switch_index] = dst;
+
         wire_to_net[dst.index] = net;
         net->wires[dst].pip = pip;
         net->wires[dst].strength = strength;
@@ -627,7 +628,7 @@ struct Arch : BaseCtx
     {
         NPNR_ASSERT(pip != PipId());
         NPNR_ASSERT(pip_to_net[pip.index] != nullptr);
-        NPNR_ASSERT(switches_locked[chip_info->pip_data[pip.index].switch_index] != nullptr);
+        NPNR_ASSERT(switches_locked[chip_info->pip_data[pip.index].switch_index] != WireId());
 
         WireId dst;
         dst.index = chip_info->pip_data[pip.index].dst;
@@ -636,7 +637,7 @@ struct Arch : BaseCtx
         pip_to_net[pip.index]->wires.erase(dst);
 
         pip_to_net[pip.index] = nullptr;
-        switches_locked[chip_info->pip_data[pip.index].switch_index] = nullptr;
+        switches_locked[chip_info->pip_data[pip.index].switch_index] = WireId();
         refreshUiPip(pip);
         refreshUiWire(dst);
     }
@@ -647,7 +648,7 @@ struct Arch : BaseCtx
         auto &pi = chip_info->pip_data[pip.index];
         auto &si = chip_info->bits_info->switches[pi.switch_index];
 
-        if (switches_locked[pi.switch_index] != nullptr)
+        if (switches_locked[pi.switch_index] != WireId())
             return false;
 
         if (pi.flags & PipInfoPOD::FLAG_ROUTETHRU) {
@@ -672,6 +673,13 @@ struct Arch : BaseCtx
     }
 
     NetInfo *getConflictingPipNet(PipId pip) const
+    {
+        NPNR_ASSERT(pip != PipId());
+        WireId wire = switches_locked[chip_info->pip_data[pip.index].switch_index];
+        return wire == WireId() ? nullptr : wire_to_net[wire.index];
+    }
+
+    WireId getConflictingPipWire(PipId pip) const
     {
         NPNR_ASSERT(pip != PipId());
         return switches_locked[chip_info->pip_data[pip.index].switch_index];