Add router1 cfg.useEstimate, improve getActualRouteDelay

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

common/nextpnr.h

@@ -484,7 +484,8 @@ struct Context : Arch, DeterministicRNG
     delay_t getNetinfoRouteDelay(const NetInfo *net_info, const PortRef &sink) const;
 
     // provided by router1.cc
-    bool getActualRouteDelay(WireId src_wire, WireId dst_wire, delay_t &delay);
+    bool getActualRouteDelay(WireId src_wire, WireId dst_wire, delay_t &delay,
+                             std::unordered_map<WireId, PipId> *route = nullptr, bool useEstimate = true);
 
     // --------------------------------------------------------------
 

common/router1.cc

@@ -130,7 +130,8 @@ struct Router
             qw.wire = it.first;
             qw.pip = PipId();
             qw.delay = it.second - (it.second / 16);
-            qw.togo = ctx->estimateDelay(qw.wire, dst_wire);
+            if (cfg.useEstimate)
+                qw.togo = ctx->estimateDelay(qw.wire, dst_wire);
             qw.randtag = ctx->rng();
 
             queue.push(qw);
@@ -216,7 +217,8 @@ struct Router
                 next_qw.wire = next_wire;
                 next_qw.pip = pip;
                 next_qw.delay = next_delay;
-                next_qw.togo = ctx->estimateDelay(next_wire, dst_wire);
+                if (cfg.useEstimate)
+                    next_qw.togo = ctx->estimateDelay(next_wire, dst_wire);
                 next_qw.randtag = ctx->rng();
 
                 visited[next_qw.wire] = next_qw;
@@ -945,13 +947,32 @@ bool router1(Context *ctx, const Router1Cfg &cfg)
     }
 }
 
-bool Context::getActualRouteDelay(WireId src_wire, WireId dst_wire, delay_t &delay)
+bool Context::getActualRouteDelay(WireId src_wire, WireId dst_wire, delay_t &delay,
+                                  std::unordered_map<WireId, PipId> *route, bool useEstimate)
 {
     RipupScoreboard scores;
-    Router router(this, Router1Cfg(), scores, src_wire, dst_wire);
-    if (router.routedOkay)
-        delay = router.visited.at(dst_wire).delay;
-    return router.routedOkay;
+    Router1Cfg cfg;
+    cfg.useEstimate = useEstimate;
+
+    Router router(this, cfg, scores, src_wire, dst_wire);
+
+    if (!router.routedOkay)
+        return false;
+
+    delay = router.visited.at(dst_wire).delay;
+
+    if (route != nullptr) {
+        WireId cursor = dst_wire;
+        while (1) {
+            PipId pip = router.visited.at(cursor).pip;
+            (*route)[cursor] = pip;
+            if (pip == PipId())
+                break;
+            cursor = getPipSrcWire(pip);
+        }
+    }
+
+    return true;
 }
 
 NEXTPNR_NAMESPACE_END

common/router1.h

@@ -29,6 +29,7 @@ struct Router1Cfg
     int maxIterCnt = 200;
     bool cleanupReroute = true;
     bool fullCleanupReroute = true;
+    bool useEstimate = true;
 };
 
 extern bool router1(Context *ctx, const Router1Cfg &cfg);