Merge branch 'master' into redist_slack

7 files changed, 457 insertions, 253 deletions

diff --git a/common/archcheck.cc b/common/archcheck.cc
new file mode 100644
index 00000000..5c4ef26c
--- /dev/null
+++ b/common/archcheck.cc
@@ -0,0 +1,146 @@
+/*
+ *  nextpnr -- Next Generation Place and Route
+ *
+ *  Copyright (C) 2018  Clifford Wolf <clifford@symbioticeda.com>
+ *
+ *  Permission to use, copy, modify, and/or distribute this software for any
+ *  purpose with or without fee is hereby granted, provided that the above
+ *  copyright notice and this permission notice appear in all copies.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ *  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ *  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ *  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ *  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ *  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ *  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+#include "nextpnr.h"
+#include "log.h"
+
+#if 0
+#define dbg(...) log(__VA_ARGS__)
+#else
+#define dbg(...)
+#endif
+
+USING_NEXTPNR_NAMESPACE
+
+namespace {
+
+void archcheck_names(const Context *ctx)
+{
+    log_info("Checking entity names.\n");
+
+    log_info("Checking bel names..\n");
+    for (BelId bel : ctx->getBels()) {
+        IdString name = ctx->getBelName(bel);
+        BelId bel2 = ctx->getBelByName(name);
+        log_assert(bel == bel2);
+    }
+
+    log_info("Checking wire names..\n");
+    for (WireId wire : ctx->getWires()) {
+        IdString name = ctx->getWireName(wire);
+        WireId wire2 = ctx->getWireByName(name);
+        log_assert(wire == wire2);
+    }
+
+    log_info("Checking pip names..\n");
+    for (PipId pip : ctx->getPips()) {
+        IdString name = ctx->getPipName(pip);
+        PipId pip2 = ctx->getPipByName(name);
+        log_assert(pip == pip2);
+    }
+
+    log_break();
+}
+
+void archcheck_locs(const Context *ctx)
+{
+    log_info("Checking location data.\n");
+
+    log_info("Checking all bels..\n");
+    for (BelId bel : ctx->getBels()) {
+        log_assert(bel != BelId());
+        dbg("> %s\n", ctx->getBelName(bel).c_str(ctx));
+
+        Loc loc = ctx->getBelLocation(bel);
+        dbg("   ... %d %d %d\n", loc.x, loc.y, loc.z);
+
+        log_assert(0 <= loc.x);
+        log_assert(0 <= loc.y);
+        log_assert(0 <= loc.z);
+        log_assert(loc.x < ctx->getGridDimX());
+        log_assert(loc.y < ctx->getGridDimY());
+        log_assert(loc.z < ctx->getTileDimZ(loc.x, loc.y));
+
+        BelId bel2 = ctx->getBelByLocation(loc);
+        dbg("   ... %s\n", ctx->getBelName(bel2).c_str(ctx));
+        log_assert(bel == bel2);
+    }
+
+    log_info("Checking all locations..\n");
+    for (int x = 0; x < ctx->getGridDimX(); x++)
+        for (int y = 0; y < ctx->getGridDimY(); y++)
+        {
+            dbg("> %d %d\n", x, y);
+            std::unordered_set<int> usedz;
+
+            for (int z = 0; z < ctx->getTileDimZ(x, y); z++) {
+                BelId bel = ctx->getBelByLocation(Loc(x, y, z));
+                if (bel == BelId())
+                    continue;
+                Loc loc = ctx->getBelLocation(bel);
+                dbg("   + %d %s\n", z, ctx->getBelName(bel).c_str(ctx));
+                log_assert(x == loc.x);
+                log_assert(y == loc.y);
+                log_assert(z == loc.z);
+                usedz.insert(z);
+            }
+
+            for (BelId bel : ctx->getBelsByTile(x, y)) {
+                Loc loc = ctx->getBelLocation(bel);
+                dbg("   - %d %s\n", loc.z, ctx->getBelName(bel).c_str(ctx));
+                log_assert(x == loc.x);
+                log_assert(y == loc.y);
+                log_assert(usedz.count(loc.z));
+                usedz.erase(loc.z);
+            }
+
+            log_assert(usedz.empty());
+        }
+
+    log_break();
+}
+
+void archcheck_conn(const Context *ctx)
+{
+#if 0
+    log_info("Checking connectivity data.\n");
+
+    log_info("Checking all wires..\n");
+    for (WireId wire : ctx->getWires())
+    {
+        ...
+    }
+#endif
+}
+
+} // namespace
+
+NEXTPNR_NAMESPACE_BEGIN
+
+void Context::archcheck() const
+{
+    log_info("Running architecture database integrity check.\n");
+    log_break();
+
+    archcheck_names(this);
+    archcheck_locs(this);
+    archcheck_conn(this);
+}
+
+NEXTPNR_NAMESPACE_END
diff --git a/common/log.h b/common/log.h
index c3607e39..35450311 100644
--- a/common/log.h
+++ b/common/log.h
@@ -69,17 +69,13 @@ NPNR_NORETURN void log_cmd_error(const char *format, ...) NPNR_ATTRIBUTE(format(
 void log_break();
 void log_flush();
 
-#ifndef NDEBUG
 static inline void log_assert_worker(bool cond, const char *expr, const char *file, int line)
 {
     if (!cond)
         log_error("Assert `%s' failed in %s:%d.\n", expr, file, line);
 }
 #define log_assert(_assert_expr_)                                                                                      \
-    YOSYS_NAMESPACE_PREFIX log_assert_worker(_assert_expr_, #_assert_expr_, __FILE__, __LINE__)
-#else
-#define log_assert(_assert_expr_)
-#endif
+    NEXTPNR_NAMESPACE_PREFIX log_assert_worker(_assert_expr_, #_assert_expr_, __FILE__, __LINE__)
 
 #define log_abort() log_error("Abort in %s:%d.\n", __FILE__, __LINE__)
 #define log_ping() log("-- %s:%d %s --\n", __FILE__, __LINE__, __PRETTY_FUNCTION__)
diff --git a/common/nextpnr.cc b/common/nextpnr.cc
index 3861e5fe..2c50c9a1 100644
--- a/common/nextpnr.cc
+++ b/common/nextpnr.cc
@@ -51,6 +51,67 @@ void IdString::initialize_add(const BaseCtx *ctx, const char *s, int idx)
     ctx->idstring_idx_to_str->push_back(&insert_rc.first->first);
 }
 
+WireId Context::getNetinfoSourceWire(NetInfo *net_info) const
+{
+    if (net_info->driver.cell == nullptr)
+        return WireId();
+
+    auto src_bel = net_info->driver.cell->bel;
+
+    if (src_bel == BelId())
+        return WireId();
+
+    IdString driver_port = net_info->driver.port;
+
+    auto driver_port_it = net_info->driver.cell->pins.find(driver_port);
+    if (driver_port_it != net_info->driver.cell->pins.end())
+        driver_port = driver_port_it->second;
+
+    return getBelPinWire(src_bel, portPinFromId(driver_port));
+}
+
+WireId Context::getNetinfoSinkWire(NetInfo *net_info, int user_idx) const
+{
+    auto &user_info = net_info->users[user_idx];
+    auto dst_bel = user_info.cell->bel;
+
+    if (dst_bel == BelId())
+        return WireId();
+
+    IdString user_port = user_info.port;
+
+    auto user_port_it = user_info.cell->pins.find(user_port);
+
+    if (user_port_it != user_info.cell->pins.end())
+        user_port = user_port_it->second;
+
+    return getBelPinWire(dst_bel, portPinFromId(user_port));
+}
+
+delay_t Context::getNetinfoRouteDelay(NetInfo *net_info, int user_idx) const
+{
+    WireId src_wire = getNetinfoSourceWire(net_info);
+    WireId cursor = getNetinfoSinkWire(net_info, user_idx);
+    delay_t delay = 0;
+
+    while (cursor != WireId() && cursor != src_wire) {
+        auto it = net_info->wires.find(cursor);
+        if (it == net_info->wires.end())
+            break;
+        PipId pip = it->second.pip;
+        delay += getPipDelay(pip).maxDelay();
+        delay += getWireDelay(cursor).maxDelay();
+        cursor = getPipSrcWire(pip);
+    }
+
+    if (cursor == src_wire)
+        delay += getWireDelay(src_wire).maxDelay();
+    else
+        delay += estimateDelay(src_wire, cursor);
+
+    return delay;
+}
+
 static uint32_t xorshift32(uint32_t x)
 {
     x ^= x << 13;
diff --git a/common/nextpnr.h b/common/nextpnr.h
index 40fd3d13..021772fe 100644
--- a/common/nextpnr.h
+++ b/common/nextpnr.h
@@ -2,6 +2,7 @@
  *  nextpnr -- Next Generation Place and Route
  *
  *  Copyright (C) 2018  Clifford Wolf <clifford@symbioticeda.com>
+ *  Copyright (C) 2018  Serge Bazanski <q3k@symbioticeda.com>
  *
  *  Permission to use, copy, modify, and/or distribute this software for any
  *  purpose with or without fee is hereby granted, provided that the above
@@ -19,7 +20,10 @@
 
 #include <algorithm>
 #include <assert.h>
+#include <condition_variable>
 #include <memory>
+#include <mutex>
+#include <pthread.h>
 #include <stdexcept>
 #include <stdint.h>
 #include <string>
@@ -164,6 +168,9 @@ struct Loc
 {
     int x = -1, y = -1, z = -1;
 
+    Loc() {}
+    Loc(int x, int y, int z) : x(x), y(y), z(z) {}
+
     bool operator==(const Loc &other) const { return (x == other.x) && (y == other.y) && (z == other.z); }
     bool operator!=(const Loc &other) const { return (x != other.x) || (y != other.y) || (z == other.z); }
 };
@@ -267,19 +274,87 @@ struct CellInfo : ArchCellInfo
     std::unordered_map<IdString, IdString> pins;
 };
 
-struct BaseCtx
+struct DeterministicRNG
 {
-    // --------------------------------------------------------------
+    uint64_t rngstate;
 
-    mutable std::unordered_map<std::string, int> *idstring_str_to_idx;
-    mutable std::vector<const std::string *> *idstring_idx_to_str;
+    DeterministicRNG() : rngstate(0x3141592653589793) {}
 
-    IdString id(const std::string &s) const { return IdString(this, s); }
+    uint64_t rng64()
+    {
+        // xorshift64star
+        // https://arxiv.org/abs/1402.6246
 
-    IdString id(const char *s) const { return IdString(this, s); }
+        uint64_t retval = rngstate * 0x2545F4914F6CDD1D;
 
-    // --------------------------------------------------------------
+        rngstate ^= rngstate >> 12;
+        rngstate ^= rngstate << 25;
+        rngstate ^= rngstate >> 27;
+
+        return retval;
+    }
 
+    int rng() { return rng64() & 0x3fffffff; }
+
+    int rng(int n)
+    {
+        assert(n > 0);
+
+        // round up to power of 2
+        int m = n - 1;
+        m |= (m >> 1);
+        m |= (m >> 2);
+        m |= (m >> 4);
+        m |= (m >> 8);
+        m |= (m >> 16);
+        m += 1;
+
+        while (1) {
+            int x = rng64() & (m - 1);
+            if (x < n)
+                return x;
+        }
+    }
+
+    void rngseed(uint64_t seed)
+    {
+        rngstate = seed ? seed : 0x3141592653589793;
+        for (int i = 0; i < 5; i++)
+            rng64();
+    }
+
+    template <typename T> void shuffle(std::vector<T> &a)
+    {
+        for (size_t i = 0; i != a.size(); i++) {
+            size_t j = i + rng(a.size() - i);
+            if (j > i)
+                std::swap(a[i], a[j]);
+        }
+    }
+
+    template <typename T> void sorted_shuffle(std::vector<T> &a)
+    {
+        std::sort(a.begin(), a.end());
+        shuffle(a);
+    }
+};
+
+struct BaseCtx
+{
+    // Lock to perform mutating actions on the Context.
+    std::mutex mutex;
+    pthread_t mutex_owner;
+
+    // Lock to be taken by UI when wanting to access context - the yield()
+    // method will lock/unlock it when its' released the main mutex to make
+    // sure the UI is not starved.
+    std::mutex ui_mutex;
+
+    // ID String database.
+    mutable std::unordered_map<std::string, int> *idstring_str_to_idx;
+    mutable std::vector<const std::string *> *idstring_idx_to_str;
+
+    // Placed nets and cells.
     std::unordered_map<IdString, std::unique_ptr<NetInfo>> nets;
     std::unordered_map<IdString, std::unique_ptr<CellInfo>> cells;
 
@@ -297,13 +372,57 @@ struct BaseCtx
         delete idstring_idx_to_str;
     }
 
+    // Must be called before performing any mutating changes on the Ctx/Arch.
+    void lock(void)
+    {
+        mutex.lock();
+        mutex_owner = pthread_self();
+    }
+
+    void unlock(void)
+    {
+        NPNR_ASSERT(pthread_equal(pthread_self(), mutex_owner) != 0);
+        mutex.unlock();
+    }
+
+    // Must be called by the UI before rendering data. This lock will be
+    // prioritized when processing code calls yield().
+    void lock_ui(void)
+    {
+        ui_mutex.lock();
+        mutex.lock();
+    }
+
+    void unlock_ui(void)
+    {
+        mutex.unlock();
+        ui_mutex.unlock();
+    }
+
+    // Yield to UI by unlocking the main mutex, flashing the UI mutex and
+    // relocking the main mutex. Call this when you're performing a
+    // long-standing action while holding a lock to let the UI show
+    // visualization updates.
+    // Must be called with the main lock taken.
+    void yield(void)
+    {
+        unlock();
+        ui_mutex.lock();
+        ui_mutex.unlock();
+        lock();
+    }
+
+    IdString id(const std::string &s) const { return IdString(this, s); }
+
+    IdString id(const char *s) const { return IdString(this, s); }
+
     Context *getCtx() { return reinterpret_cast<Context *>(this); }
 
     const Context *getCtx() const { return reinterpret_cast<const Context *>(this); }
 
     // --------------------------------------------------------------
 
-    bool allUiReload = false;
+    bool allUiReload = true;
     bool frameUiReload = false;
     std::unordered_set<BelId> belUiReload;
     std::unordered_set<WireId> wireUiReload;
@@ -329,7 +448,7 @@ NEXTPNR_NAMESPACE_END
 
 NEXTPNR_NAMESPACE_BEGIN
 
-struct Context : Arch
+struct Context : Arch, DeterministicRNG
 {
     bool verbose = false;
     bool debug = false;
@@ -341,74 +460,19 @@ struct Context : Arch
 
     // --------------------------------------------------------------
 
+    WireId getNetinfoSourceWire(NetInfo *net_info) const;
+    WireId getNetinfoSinkWire(NetInfo *net_info, int user_idx) const;
+    delay_t getNetinfoRouteDelay(NetInfo *net_info, int user_idx) const;
+
     // provided by router1.cc
     bool getActualRouteDelay(WireId src_wire, WireId dst_wire, delay_t &delay);
 
     // --------------------------------------------------------------
 
-    uint64_t rngstate = 0x3141592653589793;
-
-    uint64_t rng64()
-    {
-        // xorshift64star
-        // https://arxiv.org/abs/1402.6246
-
-        uint64_t retval = rngstate * 0x2545F4914F6CDD1D;
-
-        rngstate ^= rngstate >> 12;
-        rngstate ^= rngstate << 25;
-        rngstate ^= rngstate >> 27;
-
-        return retval;
-    }
-
-    int rng() { return rng64() & 0x3fffffff; }
-
-    int rng(int n)
-    {
-        assert(n > 0);
-
-        // round up to power of 2
-        int m = n - 1;
-        m |= (m >> 1);
-        m |= (m >> 2);
-        m |= (m >> 4);
-        m |= (m >> 8);
-        m |= (m >> 16);
-        m += 1;
-
-        while (1) {
-            int x = rng64() & (m - 1);
-            if (x < n)
-                return x;
-        }
-    }
-
-    void rngseed(uint64_t seed)
-    {
-        rngstate = seed ? seed : 0x3141592653589793;
-        for (int i = 0; i < 5; i++)
-            rng64();
-    }
-
-    template <typename T> void shuffle(std::vector<T> &a)
-    {
-        for (size_t i = 0; i != a.size(); i++) {
-            size_t j = i + rng(a.size() - i);
-            if (j > i)
-                std::swap(a[i], a[j]);
-        }
-    }
-
-    template <typename T> void sorted_shuffle(std::vector<T> &a)
-    {
-        std::sort(a.begin(), a.end());
-        shuffle(a);
-    }
-
     uint32_t checksum() const;
 
     void check() const;
+    void archcheck() const;
 };
 
 NEXTPNR_NAMESPACE_END
diff --git a/common/place_common.cc b/common/place_common.cc
index 370eff23..95b7b2aa 100644
--- a/common/place_common.cc
+++ b/common/place_common.cc
@@ -36,7 +36,7 @@ wirelen_t get_net_metric(const Context *ctx, const NetInfo *net, MetricType type
     if (driver_cell->bel == BelId())
         return 0;
     ctx->estimatePosition(driver_cell->bel, driver_x, driver_y, driver_gb);
-    WireId drv_wire = ctx->getWireBelPin(driver_cell->bel, ctx->portPinFromId(net->driver.port));
+    WireId drv_wire = ctx->getBelPinWire(driver_cell->bel, ctx->portPinFromId(net->driver.port));
     if (driver_gb)
         return 0;
     float worst_slack = 1000;
@@ -48,7 +48,7 @@ wirelen_t get_net_metric(const Context *ctx, const NetInfo *net, MetricType type
         if (load_cell->bel == BelId())
             continue;
         if (ctx->timing_driven && type == MetricType::COST) {
-            WireId user_wire = ctx->getWireBelPin(load_cell->bel, ctx->portPinFromId(load.port));
+            WireId user_wire = ctx->getBelPinWire(load_cell->bel, ctx->portPinFromId(load.port));
             delay_t raw_wl = ctx->estimateDelay(drv_wire, user_wire);
             float slack = ctx->getDelayNS(load.budget) - ctx->getDelayNS(raw_wl);
             if (slack < 0)
diff --git a/common/placer1.cc b/common/placer1.cc
index be20c072..461fc4e8 100644
--- a/common/placer1.cc
+++ b/common/placer1.cc
@@ -80,6 +80,7 @@ class SAPlacer
 
         size_t placed_cells = 0;
         // Initial constraints placer
+        ctx->lock();
         for (auto &cell_entry : ctx->cells) {
             CellInfo *cell = cell_entry.second.get();
             auto loc = cell->attrs.find(ctx->id("BEL"));
@@ -118,16 +119,19 @@ class SAPlacer
         }
         std::sort(autoplaced.begin(), autoplaced.end(), [](CellInfo *a, CellInfo *b) { return a->name < b->name; });
         ctx->shuffle(autoplaced);
+        ctx->unlock();
 
         // Place cells randomly initially
         log_info("Creating initial placement for remaining %d cells.\n", int(autoplaced.size()));
 
         for (auto cell : autoplaced) {
+            ctx->lock();
             place_initial(cell);
             placed_cells++;
             if ((placed_cells - constr_placed_cells) % 500 == 0)
                 log_info("  initial placement placed %d/%d cells\n", int(placed_cells - constr_placed_cells),
                          int(autoplaced.size()));
+            ctx->unlock();
         }
         if ((placed_cells - constr_placed_cells) % 500 != 0)
             log_info("  initial placement placed %d/%d cells\n", int(placed_cells - constr_placed_cells),
@@ -136,6 +140,7 @@ class SAPlacer
         log_info("Running simulated annealing placer.\n");
 
         // Calculate metric after initial placement
+        ctx->lock();
         curr_metric = 0;
         curr_tns = 0;
         for (auto &net : ctx->nets) {
@@ -143,6 +148,7 @@ class SAPlacer
             metrics[net.first] = wl;
             curr_metric += wl;
         }
+        ctx->unlock();
 
         int n_no_progress = 0;
         wirelen_t min_metric = curr_metric;
@@ -185,6 +191,7 @@ class SAPlacer
             if (temp <= 1e-3 && n_no_progress >= 5) {
                 if (iter % 5 != 0)
                     log_info("  at iteration #%d: temp = %f, cost = %f\n", iter, temp, double(curr_metric));
+                ctx->unlock();
                 break;
             }
 
@@ -242,8 +249,12 @@ class SAPlacer
                 metrics[net.first] = wl;
                 curr_metric += wl;
             }
+
+            // Let the UI show visualization updates.
+            ctx->yield();
         }
         // Final post-pacement validitiy check
+        ctx->lock();
         for (auto bel : ctx->getBels()) {
             IdString cell = ctx->getBoundBelCell(bel);
             if (!ctx->isBelLocationValid(bel)) {
@@ -261,6 +272,7 @@ class SAPlacer
                 }
             }
         }
+        ctx->unlock();
         return true;
     }
 
@@ -446,7 +458,9 @@ bool placer1(Context *ctx)
         placer.place();
         log_info("Checksum: 0x%08x\n", ctx->checksum());
 #ifndef NDEBUG
+        ctx->lock();
         ctx->check();
+        ctx->unlock();
 #endif
         return true;
     } catch (log_execution_error_exception) {
diff --git a/common/router1.cc b/common/router1.cc
index d6fcc611..431770da 100644
--- a/common/router1.cc
+++ b/common/router1.cc
@@ -252,7 +252,8 @@ struct Router
         }
     }
 
-    Router(Context *ctx, RipupScoreboard &scores, IdString net_name, int user_idx = -1, bool reroute = false, bool ripup = false, delay_t ripup_penalty = 0)
+    Router(Context *ctx, RipupScoreboard &scores, IdString net_name, int user_idx = -1, bool reroute = false,
+           bool ripup = false, delay_t ripup_penalty = 0)
             : ctx(ctx), scores(scores), net_name(net_name), ripup(ripup), ripup_penalty(ripup_penalty)
     {
         auto net_info = ctx->nets.at(net_name).get();
@@ -263,42 +264,26 @@ struct Router
         if (ctx->debug)
             log("  Source: %s.%s.\n", net_info->driver.cell->name.c_str(ctx), net_info->driver.port.c_str(ctx));
 
-        auto src_bel = net_info->driver.cell->bel;
-
-        if (src_bel == BelId())
-            log_error("Source cell %s (%s) is not mapped to a bel.\n", net_info->driver.cell->name.c_str(ctx),
-                      net_info->driver.cell->type.c_str(ctx));
-
-        if (ctx->debug)
-            log("    Source bel: %s\n", ctx->getBelName(src_bel).c_str(ctx));
-
-        IdString driver_port = net_info->driver.port;
-
-        auto driver_port_it = net_info->driver.cell->pins.find(driver_port);
-        if (driver_port_it != net_info->driver.cell->pins.end())
-            driver_port = driver_port_it->second;
-
-        auto src_wire = ctx->getWireBelPin(src_bel, ctx->portPinFromId(driver_port));
+        auto src_wire = ctx->getNetinfoSourceWire(net_info);
 
         if (src_wire == WireId())
-            log_error("No wire found for port %s (pin %s) on source cell %s "
-                      "(bel %s).\n",
-                      net_info->driver.port.c_str(ctx), driver_port.c_str(ctx), net_info->driver.cell->name.c_str(ctx),
-                      ctx->getBelName(src_bel).c_str(ctx));
+            log_error("No wire found for port %s on source cell %s.\n", net_info->driver.port.c_str(ctx),
+                      net_info->driver.cell->name.c_str(ctx));
 
         if (ctx->debug)
             log("    Source wire: %s\n", ctx->getWireName(src_wire).c_str(ctx));
 
         std::unordered_map<WireId, delay_t> src_wires;
-        std::vector<PortRef> users_array;
+        std::vector<int> users_array;
 
         if (user_idx < 0) {
             // route all users
-            users_array = net_info->users;
+            for (int user_idx = 0; user_idx < int(net_info->users.size()); user_idx++)
+                users_array.push_back(user_idx);
             ctx->shuffle(users_array);
         } else {
             // route only the selected user
-            users_array.push_back(net_info->users[user_idx]);
+            users_array.push_back(user_idx);
         }
 
         if (reroute) {
@@ -312,32 +297,16 @@ struct Router
                 ctx->bindWire(src_wire, net_name, STRENGTH_WEAK);
             src_wires[src_wire] = ctx->getWireDelay(src_wire).maxDelay();
 
-            for (auto &user_it : net_info->users) {
-                auto dst_bel = user_it.cell->bel;
-
-                if (dst_bel == BelId())
-                    log_error("Destination cell %s (%s) is not mapped to a bel.\n", user_it.cell->name.c_str(ctx),
-                              user_it.cell->type.c_str(ctx));
-
-                if (ctx->debug)
-                    log("    Destination bel: %s\n", ctx->getBelName(dst_bel).c_str(ctx));
-
-                IdString user_port = user_it.port;
-
-                auto user_port_it = user_it.cell->pins.find(user_port);
-
-                if (user_port_it != user_it.cell->pins.end())
-                    user_port = user_port_it->second;
-
-                auto dst_wire = ctx->getWireBelPin(dst_bel, ctx->portPinFromId(user_port));
+            for (int user_idx = 0; user_idx < int(net_info->users.size()); user_idx++) {
+                auto dst_wire = ctx->getNetinfoSinkWire(net_info, user_idx);
 
                 if (dst_wire == WireId())
-                    log_error("No wire found for port %s (pin %s) on destination "
-                              "cell %s (bel %s).\n",
-                              user_it.port.c_str(ctx), user_port.c_str(ctx), user_it.cell->name.c_str(ctx),
-                              ctx->getBelName(dst_bel).c_str(ctx));
+                    log_error("No wire found for port %s on destination cell %s.\n",
+                              net_info->users[user_idx].port.c_str(ctx),
+                              net_info->users[user_idx].cell->name.c_str(ctx));
 
-                std::function<delay_t(WireId)> register_existing_path = [ctx, net_info, &src_wires, &register_existing_path](WireId wire) -> delay_t {
+                std::function<delay_t(WireId)> register_existing_path =
+                        [ctx, net_info, &src_wires, &register_existing_path](WireId wire) -> delay_t {
                     auto it = src_wires.find(wire);
                     if (it != src_wires.end())
                         return it->second;
@@ -346,7 +315,7 @@ struct Router
                     delay_t delay = register_existing_path(ctx->getPipSrcWire(pip));
                     delay += ctx->getPipDelay(pip).maxDelay();
                     delay += ctx->getWireDelay(wire).maxDelay();
-                    delay -= 2*ctx->getDelayEpsilon();
+                    delay -= 2 * ctx->getDelayEpsilon();
                     src_wires[wire] = delay;
 
                     return delay;
@@ -362,7 +331,7 @@ struct Router
                 }
 
                 register_existing_path(dst_wire);
-        check_next_user_for_existing_path:;
+            check_next_user_for_existing_path:;
             }
 
             std::vector<WireId> ripup_wires;
@@ -372,39 +341,22 @@ struct Router
 
             for (auto &it : ripup_wires) {
                 if (ctx->debug)
-                    log("  Unbind dangling wire for net %s: %s\n",
-                        net_name.c_str(ctx), ctx->getWireName(it).c_str(ctx));
+                    log("  Unbind dangling wire for net %s: %s\n", net_name.c_str(ctx),
+                        ctx->getWireName(it).c_str(ctx));
                 ctx->unbindWire(it);
             }
         }
 
-        for (auto &user_it : users_array) {
-            if (ctx->debug)
-                log("  Route to: %s.%s.\n", user_it.cell->name.c_str(ctx), user_it.port.c_str(ctx));
-
-            auto dst_bel = user_it.cell->bel;
-
-            if (dst_bel == BelId())
-                log_error("Destination cell %s (%s) is not mapped to a bel.\n", user_it.cell->name.c_str(ctx),
-                          user_it.cell->type.c_str(ctx));
-
+        for (int user_idx : users_array) {
             if (ctx->debug)
-                log("    Destination bel: %s\n", ctx->getBelName(dst_bel).c_str(ctx));
-
-            IdString user_port = user_it.port;
-
-            auto user_port_it = user_it.cell->pins.find(user_port);
+                log("  Route to: %s.%s.\n", net_info->users[user_idx].cell->name.c_str(ctx),
+                    net_info->users[user_idx].port.c_str(ctx));
 
-            if (user_port_it != user_it.cell->pins.end())
-                user_port = user_port_it->second;
-
-            auto dst_wire = ctx->getWireBelPin(dst_bel, ctx->portPinFromId(user_port));
+            auto dst_wire = ctx->getNetinfoSinkWire(net_info, user_idx);
 
             if (dst_wire == WireId())
-                log_error("No wire found for port %s (pin %s) on destination "
-                          "cell %s (bel %s).\n",
-                          user_it.port.c_str(ctx), user_port.c_str(ctx), user_it.cell->name.c_str(ctx),
-                          ctx->getBelName(dst_bel).c_str(ctx));
+                log_error("No wire found for port %s on destination cell %s.\n",
+                          net_info->users[user_idx].port.c_str(ctx), net_info->users[user_idx].cell->name.c_str(ctx));
 
             if (ctx->debug) {
                 log("    Destination wire: %s\n", ctx->getWireName(dst_wire).c_str(ctx));
@@ -500,35 +452,19 @@ struct RouteJob
     };
 };
 
-
-void addFullNetRouteJob(Context *ctx, IdString net_name,
-                     std::unordered_map<IdString, std::vector<bool>> &cache,
-                     std::priority_queue<RouteJob, std::vector<RouteJob>, RouteJob::Greater> &queue)
+void addFullNetRouteJob(Context *ctx, IdString net_name, std::unordered_map<IdString, std::vector<bool>> &cache,
+                        std::priority_queue<RouteJob, std::vector<RouteJob>, RouteJob::Greater> &queue)
 {
     NetInfo *net_info = ctx->nets.at(net_name).get();
 
     if (net_info->driver.cell == nullptr)
         return;
 
-    auto src_bel = net_info->driver.cell->bel;
-
-    if (src_bel == BelId())
-        log_error("Source cell %s (%s) is not mapped to a bel.\n", net_info->driver.cell->name.c_str(ctx),
-                  net_info->driver.cell->type.c_str(ctx));
-
-    IdString driver_port = net_info->driver.port;
-
-    auto driver_port_it = net_info->driver.cell->pins.find(driver_port);
-    if (driver_port_it != net_info->driver.cell->pins.end())
-        driver_port = driver_port_it->second;
-
-    auto src_wire = ctx->getWireBelPin(src_bel, ctx->portPinFromId(driver_port));
+    auto src_wire = ctx->getNetinfoSourceWire(net_info);
 
     if (src_wire == WireId())
-        log_error("No wire found for port %s (pin %s) on source cell %s "
-                  "(bel %s).\n",
-                  net_info->driver.port.c_str(ctx), driver_port.c_str(ctx), net_info->driver.cell->name.c_str(ctx),
-                  ctx->getBelName(src_bel).c_str(ctx));
+        log_error("No wire found for port %s on source cell %s.\n", net_info->driver.port.c_str(ctx),
+                  net_info->driver.cell->name.c_str(ctx));
 
     auto &net_cache = cache[net_name];
 
@@ -543,46 +479,30 @@ void addFullNetRouteJob(Context *ctx, IdString net_name,
 
     bool got_slack = false;
 
-    for (int user_idx = 0; user_idx < int(net_info->users.size()); user_idx++)
-    {
+    for (int user_idx = 0; user_idx < int(net_info->users.size()); user_idx++) {
         if (net_cache[user_idx])
             continue;
 
-        auto &user_info = net_info->users[user_idx];
-        auto dst_bel = user_info.cell->bel;
-
-        if (dst_bel == BelId())
-            log_error("Destination cell %s (%s) is not mapped to a bel.\n",
-                      user_info.cell->name.c_str(ctx), user_info.cell->type.c_str(ctx));
-
-        IdString user_port = user_info.port;
-
-        auto user_port_it = user_info.cell->pins.find(user_port);
-
-        if (user_port_it != user_info.cell->pins.end())
-            user_port = user_port_it->second;
-
-        auto dst_wire = ctx->getWireBelPin(dst_bel, ctx->portPinFromId(user_port));
+        auto dst_wire = ctx->getNetinfoSinkWire(net_info, user_idx);
 
         if (dst_wire == WireId())
-            log_error("No wire found for port %s (pin %s) on destination "
-                      "cell %s (bel %s).\n",
-                      user_info.port.c_str(ctx), user_port.c_str(ctx), user_info.cell->name.c_str(ctx),
-                      ctx->getBelName(dst_bel).c_str(ctx));
+            log_error("No wire found for port %s on destination cell %s.\n", net_info->users[user_idx].port.c_str(ctx),
+                      net_info->users[user_idx].cell->name.c_str(ctx));
 
         if (user_idx == 0)
-            job.slack = user_info.budget - ctx->estimateDelay(src_wire, dst_wire);
+            job.slack = net_info->users[user_idx].budget - ctx->estimateDelay(src_wire, dst_wire);
         else
-            job.slack = std::min(job.slack, user_info.budget - ctx->estimateDelay(src_wire, dst_wire));
+            job.slack = std::min(job.slack, net_info->users[user_idx].budget - ctx->estimateDelay(src_wire, dst_wire));
 
         WireId cursor = dst_wire;
         while (src_wire != cursor) {
             auto it = net_info->wires.find(cursor);
             if (it == net_info->wires.end()) {
                 if (!got_slack)
-                    job.slack = user_info.budget - ctx->estimateDelay(src_wire, dst_wire);
+                    job.slack = net_info->users[user_idx].budget - ctx->estimateDelay(src_wire, dst_wire);
                 else
-                    job.slack = std::min(job.slack, user_info.budget - ctx->estimateDelay(src_wire, dst_wire));
+                    job.slack = std::min(job.slack,
+                                         net_info->users[user_idx].budget - ctx->estimateDelay(src_wire, dst_wire));
                 got_slack = true;
                 break;
             }
@@ -597,8 +517,7 @@ void addFullNetRouteJob(Context *ctx, IdString net_name,
         net_cache[user_idx] = true;
 }
 
-void addNetRouteJobs(Context *ctx, IdString net_name,
-                     std::unordered_map<IdString, std::vector<bool>> &cache,
+void addNetRouteJobs(Context *ctx, IdString net_name, std::unordered_map<IdString, std::vector<bool>> &cache,
                      std::priority_queue<RouteJob, std::vector<RouteJob>, RouteJob::Greater> &queue)
 {
     NetInfo *net_info = ctx->nets.at(net_name).get();
@@ -606,73 +525,35 @@ void addNetRouteJobs(Context *ctx, IdString net_name,
     if (net_info->driver.cell == nullptr)
         return;
 
-    auto src_bel = net_info->driver.cell->bel;
-
-    if (src_bel == BelId())
-        log_error("Source cell %s (%s) is not mapped to a bel.\n", net_info->driver.cell->name.c_str(ctx),
-                  net_info->driver.cell->type.c_str(ctx));
-
-    IdString driver_port = net_info->driver.port;
-
-    auto driver_port_it = net_info->driver.cell->pins.find(driver_port);
-    if (driver_port_it != net_info->driver.cell->pins.end())
-        driver_port = driver_port_it->second;
-
-    auto src_wire = ctx->getWireBelPin(src_bel, ctx->portPinFromId(driver_port));
+    auto src_wire = ctx->getNetinfoSourceWire(net_info);
 
     if (src_wire == WireId())
-        log_error("No wire found for port %s (pin %s) on source cell %s "
-                  "(bel %s).\n",
-                  net_info->driver.port.c_str(ctx), driver_port.c_str(ctx), net_info->driver.cell->name.c_str(ctx),
-                  ctx->getBelName(src_bel).c_str(ctx));
+        log_error("No wire found for port %s on source cell %s.\n", net_info->driver.port.c_str(ctx),
+                  net_info->driver.cell->name.c_str(ctx));
 
     auto &net_cache = cache[net_name];
 
     if (net_cache.empty())
         net_cache.resize(net_info->users.size());
 
-    for (int user_idx = 0; user_idx < int(net_info->users.size()); user_idx++)
-    {
+    for (int user_idx = 0; user_idx < int(net_info->users.size()); user_idx++) {
         if (net_cache[user_idx])
             continue;
 
-        auto &user_info = net_info->users[user_idx];
-        auto dst_bel = user_info.cell->bel;
-
-        if (dst_bel == BelId())
-            log_error("Destination cell %s (%s) is not mapped to a bel.\n",
-                      user_info.cell->name.c_str(ctx), user_info.cell->type.c_str(ctx));
-
-        IdString user_port = user_info.port;
-
-        auto user_port_it = user_info.cell->pins.find(user_port);
-
-        if (user_port_it != user_info.cell->pins.end())
-            user_port = user_port_it->second;
-
-        auto dst_wire = ctx->getWireBelPin(dst_bel, ctx->portPinFromId(user_port));
+        auto dst_wire = ctx->getNetinfoSinkWire(net_info, user_idx);
 
         if (dst_wire == WireId())
-            log_error("No wire found for port %s (pin %s) on destination "
-                      "cell %s (bel %s).\n",
-                      user_info.port.c_str(ctx), user_port.c_str(ctx), user_info.cell->name.c_str(ctx),
-                      ctx->getBelName(dst_bel).c_str(ctx));
+            log_error("No wire found for port %s on destination cell %s.\n", net_info->users[user_idx].port.c_str(ctx),
+                      net_info->users[user_idx].cell->name.c_str(ctx));
 
         WireId cursor = dst_wire;
         while (src_wire != cursor) {
             auto it = net_info->wires.find(cursor);
             if (it == net_info->wires.end()) {
-                if (ctx->debug)
-                    log("Adding job [%s %d]: %s %s (%s) -> %s %s (%s)\n",
-                        net_name.c_str(ctx), user_idx,
-                        ctx->getBelName(src_bel).c_str(ctx), driver_port.c_str(ctx),
-                        ctx->getWireName(src_wire).c_str(ctx),
-                        ctx->getBelName(dst_bel).c_str(ctx), user_port.c_str(ctx),
-                        ctx->getWireName(dst_wire).c_str(ctx));
                 RouteJob job;
                 job.net = net_name;
                 job.user_idx = user_idx;
-                job.slack = user_info.budget - ctx->estimateDelay(src_wire, dst_wire);
+                job.slack = net_info->users[user_idx].budget - ctx->estimateDelay(src_wire, dst_wire);
                 job.randtag = ctx->rng();
                 queue.push(job);
                 net_cache[user_idx] = true;
@@ -697,6 +578,7 @@ bool router1(Context *ctx)
 
         log_break();
         log_info("Routing..\n");
+        ctx->lock();
 
         std::unordered_map<IdString, std::vector<bool>> jobCache;
         std::priority_queue<RouteJob, std::vector<RouteJob>, RouteJob::Greater> jobQueue;
@@ -767,7 +649,7 @@ bool router1(Context *ctx)
             bool printNets = ctx->verbose && (jobQueue.size() < 10);
 
             while (!jobQueue.empty()) {
-                if(ctx->debug)
+                if (ctx->debug)
                     log("Next job slack: %f\n", double(jobQueue.top().slack));
 
                 auto net_name = jobQueue.top().net;
@@ -776,8 +658,8 @@ bool router1(Context *ctx)
 
                 if (printNets) {
                     if (user_idx < 0)
-                        log_info("  routing all %d users of net %s\n",
-                                 int(ctx->nets.at(net_name)->users.size()), net_name.c_str(ctx));
+                        log_info("  routing all %d users of net %s\n", int(ctx->nets.at(net_name)->users.size()),
+                                 net_name.c_str(ctx));
                     else
                         log_info("  routing user %d of net %s\n", user_idx, net_name.c_str(ctx));
                 }
@@ -798,15 +680,19 @@ bool router1(Context *ctx)
                     normalRouteNets.insert(net_name);
                 }
 
-                if ((ctx->verbose || iterCnt == 1) && !printNets && (jobCnt % 100 == 0))
+                if ((ctx->verbose || iterCnt == 1) && !printNets && (jobCnt % 100 == 0)) {
                     log_info("  processed %d jobs. (%d routed, %d failed)\n", jobCnt, jobCnt - failedCnt, failedCnt);
+                    ctx->yield();
+                }
             }
 
             NPNR_ASSERT(jobQueue.empty());
             jobCache.clear();
 
-            if ((ctx->verbose || iterCnt == 1) && (jobCnt % 100 != 0))
+            if ((ctx->verbose || iterCnt == 1) && (jobCnt % 100 != 0)) {
                 log_info("  processed %d jobs. (%d routed, %d failed)\n", jobCnt, jobCnt - failedCnt, failedCnt);
+                ctx->yield();
+            }
 
             if (ctx->verbose)
                 log_info("  visited %d PIPs (%.2f%% revisits, %.2f%% overtime "
@@ -860,8 +746,10 @@ bool router1(Context *ctx)
 
                     ripCnt += router.rippedNets.size();
 
-                    if ((ctx->verbose || iterCnt == 1) && !printNets && (netCnt % 100 == 0))
+                    if ((ctx->verbose || iterCnt == 1) && !printNets && (netCnt % 100 == 0)) {
                         log_info("  routed %d nets, ripped %d nets.\n", netCnt, ripCnt);
+                        ctx->yield();
+                    }
                 }
 
                 if ((ctx->verbose || iterCnt == 1) && (netCnt % 100 != 0))
@@ -879,9 +767,8 @@ bool router1(Context *ctx)
             }
 
             if (!ctx->verbose)
-                log_info("iteration %d: routed %d nets without ripup, routed %d nets with ripup.\n",
-                         iterCnt, int(normalRouteNets.size()), int(ripupQueue.size()));
-
+                log_info("iteration %d: routed %d nets without ripup, routed %d nets with ripup.\n", iterCnt,
+                         int(normalRouteNets.size()), int(ripupQueue.size()));
 
             totalVisitCnt += visitCnt;
             totalRevisitCnt += revisitCnt;
@@ -889,6 +776,8 @@ bool router1(Context *ctx)
 
             if (iterCnt == 8 || iterCnt == 16 || iterCnt == 32 || iterCnt == 64 || iterCnt == 128)
                 ripup_penalty += ctx->getRipupDelayPenalty();
+
+            ctx->yield();
         }
 
         log_info("routing complete after %d iterations.\n", iterCnt);
@@ -898,6 +787,38 @@ bool router1(Context *ctx)
                  totalVisitCnt, (100.0 * totalRevisitCnt) / totalVisitCnt,
                  (100.0 * totalOvertimeRevisitCnt) / totalVisitCnt);
 
+        {
+            float tns = 0;
+            int tns_net_count = 0;
+            int tns_arc_count = 0;
+            for (auto &net_it : ctx->nets) {
+                bool got_negative_slack = false;
+                NetInfo *net_info = ctx->nets.at(net_it.first).get();
+                for (int user_idx = 0; user_idx < int(net_info->users.size()); user_idx++) {
+                    delay_t arc_delay = ctx->getNetinfoRouteDelay(net_info, user_idx);
+                    delay_t arc_budget = net_info->users[user_idx].budget;
+                    delay_t arc_slack = arc_budget - arc_delay;
+                    if (arc_slack < 0) {
+                        if (!got_negative_slack) {
+                            if (ctx->verbose)
+                                log_info("net %s has negative slack arcs:\n", net_info->name.c_str(ctx));
+                            tns_net_count++;
+                        }
+                        if (ctx->verbose)
+                            log_info("  arc %s -> %s has %f ns slack (delay %f, budget %f)\n",
+                                     ctx->getWireName(ctx->getNetinfoSourceWire(net_info)).c_str(ctx),
+                                     ctx->getWireName(ctx->getNetinfoSinkWire(net_info, user_idx)).c_str(ctx),
+                                     ctx->getDelayNS(arc_slack), ctx->getDelayNS(arc_delay),
+                                     ctx->getDelayNS(arc_budget));
+                        tns += ctx->getDelayNS(arc_slack);
+                        tns_arc_count++;
+                    }
+                }
+            }
+            log_info("final tns with respect to arc budgets: %f ns (%d nets, %d arcs)\n", tns, tns_net_count,
+                     tns_arc_count);
+        }
+
         NPNR_ASSERT(jobQueue.empty());
         jobCache.clear();
 
@@ -920,11 +841,13 @@ bool router1(Context *ctx)
         log_info("Checksum: 0x%08x\n", ctx->checksum());
 #ifndef NDEBUG
         ctx->check();
+        ctx->unlock();
 #endif
         return true;
     } catch (log_execution_error_exception) {
 #ifndef NDEBUG
         ctx->check();
+        ctx->unlock();
 #endif
         return false;
     }