Gowin. Fix the port check for connectivity.

What happens is that it's not enough to check for a network, we also
need to make sure that the network is functional: has src and sinks.

And the style edits - they get automatically when I make sure to run
clang-format10.

Signed-off-by: YRabbit <rabbit@yrabbit.cyou>

himbaechel/uarch/gowin/cst.cc

@@ -20,7 +20,7 @@ struct GowinCstReader
     Context *ctx;
     std::istream ∈
 
-    GowinCstReader(Context *ctx, std::istream &in) : ctx(ctx), in(in) {};
+    GowinCstReader(Context *ctx, std::istream &in) : ctx(ctx), in(in){};
 
     const PadInfoPOD *pinLookup(const PadInfoPOD *list, const size_t len, const IdString idx)
     {

himbaechel/uarch/gowin/globals.cc

@@ -340,7 +340,8 @@ struct GowinGlobalRouter
             src = ctx->getBelPinWire(driver.cell->bel, driver.port);
         }
 
-        RouteResult route_result = route_direct_net(net, [&](PipId pip) { return global_DQCE_pip_filter(pip); }, src);
+        RouteResult route_result = route_direct_net(
+                net, [&](PipId pip) { return global_DQCE_pip_filter(pip); }, src);
         if (route_result == NOT_ROUTED) {
             log_error("Can't route the %s network.\n", ctx->nameOf(net));
         }
@@ -417,7 +418,8 @@ struct GowinGlobalRouter
             src = ctx->getBelPinWire(driver.cell->bel, driver.port);
         }
 
-        RouteResult route_result = route_direct_net(net, [&](PipId pip) { return global_DCS_pip_filter(pip); }, src);
+        RouteResult route_result = route_direct_net(
+                net, [&](PipId pip) { return global_DCS_pip_filter(pip); }, src);
         if (route_result == NOT_ROUTED) {
             log_error("Can't route the %s network.\n", ctx->nameOf(net));
         }
@@ -504,7 +506,8 @@ struct GowinGlobalRouter
         WireId src = ctx->getBelPinWire(driver.cell->bel, port);
 
         std::vector<PipId> path;
-        RouteResult route_result = route_direct_net(net, [&](PipId pip) { return global_pip_filter(pip); }, src, &path);
+        RouteResult route_result = route_direct_net(
+                net, [&](PipId pip) { return global_pip_filter(pip); }, src, &path);
         if (route_result == NOT_ROUTED) {
             log_error("Can't route the %s network.\n", ctx->nameOf(net));
         }
@@ -568,7 +571,8 @@ struct GowinGlobalRouter
         NetInfo *net_before_buf = buf_ci->getPort(id_I);
         NPNR_ASSERT(net_before_buf != nullptr);
 
-        RouteResult route_result = route_direct_net(net, [&](PipId pip) { return global_pip_filter(pip); }, src);
+        RouteResult route_result = route_direct_net(
+                net, [&](PipId pip) { return global_pip_filter(pip); }, src);
         if (route_result == NOT_ROUTED || route_result == ROUTED_PARTIALLY) {
             log_error("Can't route the %s net. It might be worth removing the BUFG buffer flag.\n", ctx->nameOf(net));
         }

himbaechel/uarch/gowin/gowin.cc

@@ -21,7 +21,7 @@ namespace {
 struct GowinImpl : HimbaechelAPI
 {
 
-    ~GowinImpl() {};
+    ~GowinImpl(){};
     void init_database(Arch *arch) override;
     void init(Context *ctx) override;
 
@@ -102,7 +102,7 @@ struct GowinImpl : HimbaechelAPI
 
 struct GowinArch : HimbaechelArch
 {
-    GowinArch() : HimbaechelArch("gowin") {};
+    GowinArch() : HimbaechelArch("gowin"){};
 
     bool match_device(const std::string &device) override { return device.size() > 2 && device.substr(0, 2) == "GW"; }
 

himbaechel/uarch/gowin/gowin_utils.h

@@ -1,6 +1,7 @@
 #ifndef GOWIN_UTILS_H
 #define GOWIN_UTILS_H
 
+#include "design_utils.h"
 #include "idstringlist.h"
 #include "nextpnr_namespaces.h"
 #include "nextpnr_types.h"
@@ -37,6 +38,19 @@ struct GowinUtils
     BelId get_dcs_bel(IdString spine_name);
     BelId get_dhcen_bel(WireId hclkin_wire, IdString &side);
 
+    // ports
+    inline bool port_used(CellInfo *cell, IdString port_name)
+    {
+        if (!nextpnr_himbaechel::port_used(cell, port_name)) {
+            return false;
+        }
+        NetInfo *ni = cell->ports.at(port_name).net;
+        if (ni->driver.cell == nullptr) {
+            return false;
+        }
+        return ni->users.entries() != 0;
+    }
+
     // BSRAM
     bool has_SP32(void);
     bool need_SP_fix(void);

himbaechel/uarch/gowin/pack.cc

@@ -454,7 +454,7 @@ struct GowinPacker
         }
 
         // if Q1 is connected then disconnect it too
-        if (port_used(&ci, tx_port)) {
+        if (gwu.port_used(&ci, tx_port)) {
             NPNR_ASSERT(out_iob == net_only_drives(ctx, ci.ports.at(tx_port).net, is_iob, id_OEN, true));
             nets_to_remove.push_back(ci.getPort(tx_port)->name);
             out_iob->disconnectPort(id_OEN);
@@ -3160,7 +3160,7 @@ struct GowinPacker
             // add invertor
             int lut_idx = 0;
             auto add_inv = [&](IdString port, PortType port_type) {
-                if (!port_used(&ci, port)) {
+                if (!gwu.port_used(&ci, port)) {
                     return;
                 }